HEALTH EDUCATION RESEARCH
Theory & Practice
Vol.11 no.l 1996
Pages 77-96
Considerations for extending the transtheoretical
model of behavior change to screening mammography
William Rakowski, Catherine A.Dube1 and Michael G.Goldstein2
Abstract
This paper reviews issues that have arisen in
the process of extending the Transtheoretical
Model of behavior change (TTM) from smoking
cessation to screening mammography. Conceptual and empirical considerations are discussed.
Topics covered include defining the stages-ofadoption, writing items for the pros and cons,
and identifying processes-of-change. Differences
between smoking cessation and mammography
as health-related behaviors are reviewed, as
they have affected the adaptation of the model
(e.g. prevention versus early detection; cessation
versus initiation; periodicity; role of the provider). The fundamental appropriateness of
mammography as a behavior to which the TTM
should be extended is also addressed (i.e. clear
behavioral guidelines, effective technology, a
definitive target population). Several areas for
further development of the TTM and mammography are presented.
Introduction
The purpose of this paper is to discuss empirical,
conceptual and practical considerations that have
arisen in research extending the Transtheoretical
Model of behavior change (TTM) to the area of
screening mammography (Rakowski et al., 1992,
Department of Community Health, Brown University,
Box G-A405, Providence, RI 02912, 'Department of
Community Health, Center for Alcohol and Addiction
Studies, Brown University, Box G-BH, Providence,
RI 02912 and 2Department of Psychiatry and Human
Behavior, Division of Behavioral Medicine, Brown
University, Box G-M, Providence, RI 02912, USA
© Oxford University Press
1993a), from its original development with and
intervention application to smoking cessation (e.g.
Prochaska and DiClemente, 1983; Prochaska et al.,
1992). The TTM has generated a great deal of
literature and is being extended to several other
health-related practices (Prochaska et al., 1994).
This report is not intended to produce a standard
formula or cookbook approach that can be used
for any behavior. However, a review of issues that
may arise when applying the model to' a new
area of behavior has not been available and may
be helpful.
Overview of the TTM
Several papers describe the basic constructs of the
TTM and should be consulted for greater detail
regarding their development in smoking cessation
research (e.g. Prochaska and DiClemente, 1982,
1983, 1986, 1992). In brief, the TTM is a multilevel, psychologically-based model that integrates
current behavioral status and intention to change
behavior ('stages-of-change'), perceptions of the
reasons for and against behavior change ('pros,'
'cons' and 'decisional balance'), and strategies that
can be used to promote behavior change ('processes
of change').
At the level of overt behavior, the TTM proposes
that persons pass through a series of progressively
more committed stages in the course of changing
a health-related behavior. The five stages are:
Precontemplation (presently not doing the behavior
and not intending to start in a given time period),
Contemplation (not doing the behavior but considering starting in a given time period). Preparation (taking the first basic steps to change behavior).
77
W.Rakowski et al.
Action (has initiated a change for a specified period
of time) and Maintenance (has sustained the change
beyond the Action period, indicating long-term
commitment). The stages-of-adoption are therefore
based upon an integration of past behavior, current
behavior and future intention. The TTM also has
a cyclical feature to the stage progression, which
recognizes that persons often reach Preparation or
Action, but do not always succeed completely,
thereby returning to Precontemplation or Contemplation (i.e. a process of Relapse). This relapse
requires that the person attempt another progression
through the stages.
The TTM is prescriptive in the sense that the
five stages are defined in a way that makes them
sequential. The progression is from not intending
to change, to considering change, to taking the
first steps for changing, to implementing the change
over time. In addition, the stage of Maintenance
is achieved only after a particular amount of time
has passed in the Action stage. This length of time
is chosen by expert opinion, on the premise that a
change in behavior of that duration indicates a
high likelihood of being sustained. For example,
smoking cessation and exercise adoption use 6
months, while mammography employs two consecutive screening cycles, covering 2-3 years.
It is important to emphasize that stages-ofadoption are not used as permanent labels or
enduring personality traits. They designate a person's status, but not rigid permanent characteristics
or typologies. The term 'typologies' often implies
the existence of qualitatively different groupings,
perhaps with little potential to move between
groups and change one's 'type.' As will be discussed below, the stages-of-adoption are more
dynamic and based on the desirability of encouraging change.
These stages are, in fact, the most directly
observable and readily measurable elements of the
TTM, insofar as they are grounded in actual
behavior. However, it is necessary to understand
what promotes movement from stage to stage. In
this regard, equally important elements of the
model are the pros, cons and processes-of-change.
The pros and cons denote perceptions about the
78
positive (pros) and negative (cons) aspects of the
target behavior and of trying to change (Velicer
et al., 1985; Prochaska et al., 1994). The pros and
cons therefore highlight the reasons a person has
for wanting to change and the reasons for not
wanting to change. The pros and cons can be based
in knowledge; attitudes; personal experience; the
experiences of others; and feelings such as fear,
anxiety and self-image.
In empirical research, the pros index and cons
index are each standardized to T-scores and a
subtraction is done to arrive at an overall summary
index of 'decisional balance' regarding the
behavior. Positive values indicate a favorable
assessment of pros versus cons (a characteristic of
Action and Maintenance), negative scores indicate
an unfavorable assessment (characteristic of Precontemplation and Contemplation) and decisional
balance of about zero represents a mixed perspective (as would be likely in the transition between
Contemplation and Preparation). However, because
the pros and cons are attitudinal dispositions characteristic of the individual at any given time, they
do not completely account for why persons move
across stages. More specific behavior change mechanisms are needed.
The processes-of-change denote cognitive and
behavioral strategies by which change is actually
accomplished, such as consciousness-raising,
stimulus control and self-reevaluation. The processes-of-change therefore specify skills that persons need in order to make a change in behavior.
There are 10 processes-of-change in smoking cessation, although not each process operates at each
stage transition (Prochaska et al., 1988; Ahijevych
and Wewers, 1992). Therefore, it is movement on
the pros, cons and process-of-change which in
turn promotes movement along the more directly
observable stages-of-change.
Finally, application of the TTM in smoking
cessation also utilizes a 'temptations' construct
and a 'self-efficacy' construct in addition to the
pros, cons and processes-of-change. The temptations/self-efficacy construct taps an individual's
confidence that they can implement the desired
behavioral change. The present paper deals with
Transtheoretical model and mammography
the TIM elements of stages-of-adoption, pros,
cons and processes-of-change. There has been
virtually no literature on how women consider
mammography during the period between appointments with providers, including how they actively
prepare for or avoid such appointments. This lack
of information has hampered writing Temptations
and Self-Efficacy items because a range of 'tempting' decision-making situations for mammography
has not yet been documented. Pros, cons and
processes items have been easier to construct,
because the literature on barriers to screening has
concentrated on perceived positives and negatives
about the procedure.
Assessment of these TTM dimensions tracks
individuals into interventions which are 'matched'
to their stage of readiness to alter behavior. The
objective of intervention is to move the individual
from one stage to the next (e.g. Contemplation to
Preparation), rather than trying to achieve rapid
transitions across stages (e.g. from Precontemplation directly to Action). In fact, over short time
periods it may not be possible to meet the criterion
for a substantial stage transition. For example, if
Maintenance requires a sustained change over 6
months, then a 3-month follow-up can capture a
transition from Precontemplation or Contemplation
into Action, but not into Maintenance.
Considerations in extending the
model
Our extension of the TTM to screening mammography has proceeded with two agendas in mind. One
is the need for empirically-based theory development and construct validation, as was done initially
to develop elements of the model with smoking
cessation and now with other behaviors (Prochaska
et al., 1994). The second agenda is to help make the
TTM efficient and usable in as many communitybased, public health contexts as possible. This
second objective can be challenging, because many
settings do not have resources to do detailed
assessments of the TTM's full set of elements.
Should the model be applied?
Prior to any item construction or data collection,
a primary consideration was whether the TTM
should be applied to screening mammography in
the first place. In order for the TTM to be applied,
there must be reliable and safe technology for
intervention, the target behavior must have volitional elements, and there should be clear
behavioral guidelines for performance by a specific
target population.
Two of these criteria seemed to be sufficiently
satisfied. The quality of screening technology has
improved greatly through the 1980s and into the
1990s. Moreover, recent federal legislation to
require certification of mammography facilities
(The Mammography Standards Quality Assurance
Act), effective October 1994, is important for
ensuring that women will not have a high risk of
adverse outcomes due to poor technology.
With regard to the volitional features of the target
behavior, the TTM concentrates on intentional
behavior, relying on personal motivation and
decision making. Mammography fulfills these criteria in many respects, although some additional
considerations are raised at the end of this paper.
Obtaining a mammogram involves making and
keeping medical appointments. It is likely that the
woman will have to discuss the procedure with her
primary care provider. The procedure is obtained
outside of one's residence and usually not at one's
primary care office, so that a separate trip to a
radiology site is necessary. In addition, because
mammograms should be obtained on a regular
schedule, the process gets repeated every year
or two.
Existence of clear behavioral guidelines
A third consideration was the existence of guidelines for action, in a specific target population.
Although the TTM is used to study how persons
adopt and change behaviors, it is ultimately an
intervention-directed model. When using the TTM,
studying how people make a decision about
behavior is secondary to knowing how persons
make what experts consider to be the proper,
health-sustaining decision. If individuals disagree
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W.Rakowski et al.
with a pros statement (about the benefits of change),
or agree with a cons statement (about reasons for
not changing), the investigators must be comfortable with the ethical implications of conducting
intervention to encourage persons to change their
points of view and their behavior. Smoking was
an appropriate health-related practice for development of the TTM because of the overwhelming
consensus regarding its harmful effects. Pros, cons
and process-of-change statements can be based on
clear guidelines for the desired, health-promoting
course of action.
In fact, mammography has become an excellent
case study for the occurrence of shifting behavioral
guidelines and its implications for the applicability
of the TTM. Prior to 1988, there had been discrepant recommendations—particularly between two
highly visible and influential organizations. The
National Cancer Institute (NCI) and The American
Cancer Society. Then, in 1988, 12 national organizations reached consensus on age-specific screening intervals (Dodd, 1992). Although the American
College of Physicians and The United States Preventive Services Task Force (Miller, 1991; Woolf,
1992) were not a part of that consensus, the
predominant recommendation was universal
screening every year or two for asymptomatic
women aged 40-49 and yearly screening for
women age 50 and oldei'. Women aged 75 and
older still posed some difficulty, due to the absence
of clinical trials data in that age group (Costanza,
1992). Because of this consensus on the target
behavior and population group, it was defensible
to write, TTM pros, cons and process items that
used age 40-75 as a reference.
The situation changed in 1993, as a result of the
NCI's review of the effectiveness of screening
mammography, with a special focus on women
aged 40-49 (Fletcher et al., 1993a). This review
led to a revision of the NCI's statement of scientific
evidence. Support for the universal screening
recommendation for women aged 40-49 was eliminated The report also indicated that evidence
demonstrated a benefit of mammography for
asymptomatic women aged 50-70 when done every
year or two, rather than saying strictly every year.
80
Lastly, it added a health-related stipulation for
continuing to screen women over age 70.
Other major national organizations have not
adopted the NCI's changes. Therefore, the guidelines for screening mammography have become
more ambiguous, especially for women aged 4049. That ambiguity is transferred to persons who
wish to apply the TTM to mammography. Those
who follow the 1993 NCI revision will restrict
their studies, and age references (if any are made)
in pros and cons statements, to women aged 50 to
age 70 or 75. Items may also need to be phrased
with a time frame of screening 'every year or two'
rather than yearly. Based on the NCI review! work
with women aged 40—49 could not encourage
universal screening. Instead, the focus would have
to be on particular subgroups (e.g. women at higher
risk due to personal or family history). In contrast,
those who adopt the screening guidelines advocated
by the American Cancer Society and other organizations would defend pros and cons items with
age 40 as a lower boundary.
Mammography versus smoking as
behaviors
A large part of the challenge in translating the
TTM from smoking cessation to screening mammography has come from differences between the
two behaviors. Because of these differences, the
large majority of statements reported in the literature to assess the pros, cons and processes-ofchange for smoking cessation were not easily
adaptable to mammography. Almost all of our
items have therefore been written from scratch, by
attending to women's opinions about screening as
reported in the literature and through focus groups.
Table I summarizes several of the key distinctions.
Addictive and problem-oriented behaviors
The development of the TTM with smoking was
based on an addictive behavior, in the context
of clinical psychology (e.g. Prochaska and
DiClemente, 1983, 1992). However, the physical
addiction of smoking has no direct translation
to mammography. Women do not routinely seek
treatment or professional advice for the 'problem'
Transtheoretical model and mammography
of not having regular mammograms. Therefore,
the wording of pros, cons and process items cannot
presume women perceive a problem that needs to
be resolved.
Prevention versus early detection
The objective of smoking cessation is prevention
(e.g. lung cancer, heart disease, stroke, respiratory
problems). Cessation may also reverse some subclinical pathological changes. Risk assessment
techniques provide persons with estimates of years
of life gained as a function of time quit Smokers
cannot be promised that they will never get smoking-related illnesses after they quit, but longer
time quit equates with a progressively lower risk
(Fielding, 1992).
There is as yet no way to prevent breast cancer.
Moreover, breast cancer rates increase with age
(Kessler, 1992; Kelsey and Hom-Ross, 1992);
repeated mammograms do not reduce the risk of
cancer incidence. Every mammogram is a new
situation, with a yes/no verdict regarding the presence of cancer. The best that can be promised
from regular screening is early detection, so that
successful treatment is likely and the need for
surgery is minimized.
Periodicity of the behavior
Because smoking occurs several times a day, there
are repeated temptations to smoke and challenges
to quit—or to relapse from quitting. The dynamics
of behavior change are played out several times
a day. In contrast, the screening mammography
guidelines use every year or two as the recommended interval. Little attention has been paid to
how women think about mammograms in the
period between appointments. The premise seems
to be that mammograms are a discrete event,
though more data are needed on this topic.
Identification with the behavior
Persons identify themselves as smokers or nonsmokers. Society reinforces this distinction with
regulations on smoking in public places. Passive
smoke has effects that extend beyond the individual. Therefore, other persons also apply sanctions against the person who smokes, Changing
behavior by quitting smoking can effect both
private and public definitions of one's self. In
contrast, mammography is a private behavior.
There are no outward signs of one's screening
status, nor are there 'secondary' or passive effects
of failing to be screened. No data exist on the selfimages of women who are not screened regularly.
Cessation versus initiation
Smoking has been approached from the standpoint
of cessation or prevention of starting, while mammography is a behavior which women need to
initiate and maintain. The 'Precontemplator' for
smoking is a smoker who is not intending to quit/
stop, while for mammography the Precontemplator
is an unscreened woman who is not intending to
start. The goal of smoking cessation is to quit a
clearly harmful habit and sustain the quit, while
mammography entails starting a behavior and
maintaining it
It is true that smoking cessation entails starting
the behavior of not smoking, and having regular
mammography entails the behavior of stopping
the habit of not having mammograms. Perhaps
mammography research should give more attention
to interventions designed to stop behaviors counterproductive to screening, not just starting the
desired one.
Locus of behavior change and/or service delivery
Smoking cessation can be done at the individual's
own residence and on the person's own schedule.
There are self-help books, videotapes and other
aids which allow the person to deliver the service
to themselves. Persons who are stopping smoking
become investigators of their own behavior. Health
care professionals are an avenue for facilitating
cessation, but are still only one of several. If the
health care provider is involved, if a medical aid
is prescribed (e.g. nicotine gum, a transdermal
patch) or if the individual attends group programs,
it is still necessary to implement the cessation
strategies personally. A large percentage of smoking cessation is achieved by the person, without
the help of formal intervention (Fiore et al., 1990;
Fielding, 1992).
81
W.Rakowski et al.
In contrast, mammograms cannot be done in
private. Mammograms are usually not obtained at
the primary care provider's office, a separate visit
to a radiology facility is required. In addition,
mammography involves a technology (i.e. medical
hardware) and the delivery of the service with
its accompanying interpersonal elements (i.e. die
technologist's skills and subsequent reporting of
the results by the radiologist or personal physician).
The receipt of mammography cannot be separated
from contact with health care providers. Bad
experiences due to discomfort, machine malfunction or indelicate procedures by die technician can
generate unfavorable opinions (cons) despite a
perception that the test is beneficial (pros) when
done properly.
Presence of medical risk
Smoking cessation has the potential side effects
of weight gain, irritability, cravings, depression,
difficulty concentrating and possible hostility
(Fielding, 1992). These are real barriers in the
minds of persons contemplating a quit attempt and
cannot be downplayed in intervention planning.
However, there are no substantial threats to medical
health that come from quitting. The absence of
risk allows presenting a consistent message to
virtually all persons who smoke.
Mammography carries the risk of abnormal,
suspicious or false positive films; and this probability accumulates over a series of mammograms.
Abnormal films lead to further mammographic
monitoring at best, but perhaps also to invasive
biopsies and the anxiety of not immediately knowing the results. Mammograms do not find all
cancers due to masking by dense breast tissue and
diere is the very minimal but still existent risk due
to radiation exposure. Therefore, concern can exist
even when mammograms are performed at accredited radiology facilities.
Defining the stages-of-adoption
The basic stages of the TTM are Precontemplation,
Contemplation, Preparation, Action and Maintenance. Relapse is a process that can take the
82
individual from Action or Maintenance back to
Precontemplation, Contemplation or Preparation.
These stages appear to be intuitively meaningful
for mammography as well (Rakowski et al., 1992,
1993a; Skinner etal., 1994). Because of the nature
of mammography behavior, however, several considerations have arisen in defining the stages.
Integration of behavior and intention
Stage-of-adoption is determined by behavioral status and future intention. The definitions of Precontemplation and Contemplation for smoking
Cessation are based on both current behavior and
intention to quit within a specific period of time.
Preparation, Action and Maintenance are defined
based on duration of die quit attempt, but traditionally diese stages have not included any statement
of intention to continue with not smoking.
We followed the combined behavior-intention
model for defining stages of mammography adoption for Precontemplation and Contemplation, but
the 1-2 year interval between screenings led us to
think diat intention for future screening might be
important even among women who were already
on dieir age-recommended schedule. A series of
mammograms diat were normal might prompt
women to believe they could delay Uieir next one.
Therefore, the Action and Maintenance stages also
augment mammography history with die intended
time of the next mammogram. Women must indicate an intention to continue on die age-recommended schedule.
The usefulness of adding intention to mammography history is shown in Table II. These data are
from a 1991 survey of 676 randomly chosen
women aged 40-79 in Rhode Island, on the topic
of breast and cervical cancer screening. One report
from this survey (Rakowski et al., 1993b) replicated an earlier study, on a smaller worksite-based
sample, which found a relationship between stagesof-adoption and decisional balance (Rakowski
etal., 1992).
Table II shows results of another analysis, not
published, which examined decisional balance as
a function of future intention for screening, within
each of five groups based on recency of screening
Transtheoretical model and mammography
Table I. A comparison of smoking and screening mammography on characteristics that influenced the writing of pros, cons and
processes statements
Behavioral characteristic
Mammography versus smoking
(1) Addiction and problem
orientation
Smoking is an addictive behavior, which is labeled as a 'problem' that needs to be treated.
The status of being off-schedule for mammography does not follow an addictive model and
there is not as great a sense of urgency to remedy an immediate, daily threat to health.
The objective of smoking cessation is prevention of health problems. Risk reduction
(2) Prevention versus early
algorithms can be calculated for persons who quit. Breast cancer cannot yet be prevented.
detection
The best outcome is detection at an early, curable stage. Every mamrnogram is a new test;
prior screenings do not reduce risk.
(3) Periodicity of the behavior
Smoking is usually done several times each day. Similarly, there are numerous tempting
situations and opportunities to resist the urge to smoke. Daily behavioral dynamics are
involved. Screening mammography uses 'every year or two' as the yardstick. There is little,
if any, data on how women think about mammography between medical visits.
Society labels persons as smokers or non-smokers and persons who smoke also have this as
(4) Social labeling and personal
part of their personal identification. Smoking is a public activity, reinforced by the effects of
identification
second-hand smoke. Mammography is a private behavior. Screening status is not a public
label and there are no sanctions leveled against women who are not being screened
regularly.
(5) Behavior cessation versus
Smoking has traditionally been approached from the standpoint of cessation of an existing
initiation
habit. Mammography has been studied from the standpoint of initiating a new habit.
(6) Locus of behavior change and Smoking cessation activities can occur at the individual's residence and on their own
service delivery
schedule. Persons attempting to quit become researchers and managers of their own behavior
on a daily basis. Cessation interventions can occur independently of health care providers.
Mammography is almost always obtained in conjuction with a primary care provider and a
technologist who performs the procedure. Medical system gatekeepers are integrally
involved in the receipt of mammograpms and in follow-up after the procedure is performed.
No serious health risks accompany smoking cessation, although nicotine withdrawal can
(7) Risk due to behavior change
have some temporary side effects and weight gain is a common fear. Mammography entails
the risk of false positives (with the need for possibly invasive follow-up) and also false
negatives (which can delay treatment).
(diagnostic mammography was kept as a separate
group). Within each of the five groups, decisional
balance changed from negative to positive as
future intention became 'very likely' or 'definite.'
Therefore, intention and prior history both seem
to contribute to defining stages-of-adoption. Other
investigators have also identified intention for
screening as a salient variable in their analyses
(Mayer et al., 1992; Stein et al., 1992; Fletcher
et al., 1993b; Mandelblatt et al., 1993; Skinner
et al., 1994).
The precontemplation stage and relapse
A Precontemplator is defined as someone who is
not currently doing the target behavior and has no
intention to do so within a reasonable future time
period. This definition can include both persons
who have never tried to adopt the target behavior,
and those who tried the behavior at some earlier
point, relapsed and are not intending to try again.
This definition can be appropriate for mammography. At the same time, mammography is still
being adopted on a society-wide level; some
women have yet to have one. Therefore, our
preference has been to retain separate groups for
the 'pure' Precontemplator (i.e. never had the
procedure and does not intend to have it), and for
women who have Relapsed (i.e. one or more prior
mammograms, now past due and expresses no
intent to have one in a specified future time
period). In an analysis of the 1990 National Health
Interview Survey on Health Promotion and Disease
Prevention (NHIS-HPDP), it was found that 25.5%
of a random, national sample of over 9000 women
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W.Rakowski et al
Table IL Means and standard deviations for decisional balance, created by cross-tabulating past screening status with intention
to have a mammogram
History-based stages of adoption
Intention to have a mammogram
No intention/don't know
Somewhat likely
Very likely/definite
-15.15
(16.29)
67
-9.16
(17.39)
24
1.52
(12.24)
42
-7.75
(1639)
21
-6.59
(1169)
16
4.35
(13.18)
53
-9.85
(18.44)
21
-3.04
(17.16)
24
5.38
(12.70)
47
-0.14
(15.31)
22
-3.18
(19.63)
20
9.78
(12.23)
209
-13.29
(20.28)
22
-4.5b
7.89
(11.18)
64
Has never had a mammogram
X
SD
n
Recent first mammogram only
X
SD
n
Past screening but not consistent
X
SD
n
On a regular schedule
X
SD
n
Recent diagnostic mammogram
X
SD
n
(11.09)
24
Table DL Guidelines for defining the stages-of-adopting mammography
Stage-of-adoption
Guidelines for staging
Precontemplalion
Relapse
Has never had a mammogram and does not plan to have one within the next 1-2 years.
Has had one or more mammograms in the past but it now off schedule and does not plan
to have a mammogram within the next 1-2 years.
Is currently on schedule, but does not plan to have another mammogram in a time period
that would keep the woman on schedule.
Has never had a mammogram, but plans to have one in the coming year, (or) is off
schedule after having a prior mammogram, but intends to have one in the coming year.
Has had one mammogram on schedule and intends to have another on a time frame that
will keep the woman on schedule. (May have had other mammograms, but only the one
most recent is on schedule.)
Has had at least two mammograms on schedule and intends to have another on a time frame
that will keep the woman on schedule.
Relapse
Contemplation
Action
Maintenance
risk
aged 40-74 were Precontemplators while another
3.9% were in Relapse (Rakowski et al., 1993b).
Our empirical work indicates that women in
Precontemplation and Relapse have a negative
decisional balance and less favorable processesof-change (Rakowski et al., 1993a, 1994). The
Precontemplation group may be somewhat more
84
negative than the Relapse group. Nonetheless, the
difference has only been in relative negativity—
both groups still are more negative than Contemplation, Action and Maintenance.
A question is whether or not to treat Relapse
as a separate stage-of-adoption. From the strict
interpretation of staging as a progression that
Transtheoretical model and mammography
women move through, Relapse is probably more
a status than a stage. Because of their similar
scores to Precontemplators, it is possible that the
two groups can be combined, as the TTM has
traditionally done. This would be especially useful
in smaller samples where the numbers in either
group might not be large enough for separate
analyses.
However, there is an intervention-oriented
reason to distinguish Relapse from Precontemplation. Women in Relapse have had at least one
mammogram. Intervention staff need to know why
a woman has lapsed away from the procedure,
including her experiences with and feelings about
prior mammograms. Some barriers to screening
may be stage-specific, so that the content of intervention messages may also be targeted more accurately by acknowledging her past action.
Defining the maintenance and action
stages
The integration of past behavior with future intention is one feature of the definition of Action and
Maintenance. A related consideration has been the
number of past mammograms that are necessary
in order to be eligible for being in Maintenance
(also presuming an intention to continue future
screening). Smoking cessation has used 6 months
as the boundary between Action and Maintenance
(Prochaska and DiClemente, 1992), but mammography operates on a 1-2 year interval. Therefore,
the definition for regular screening could involve
a period of several years, raising a concern over
'telescoping' the recall of past mammograms closer
to the present (King et al., 1990; Degnan et al.,
1992; Etzi et al., 1994), thereby introducing a
positive bias to the woman's stage classification.
In addition, the larger the number of past mammograms involved in a definition of stage, the more
questions that will be necessary. Stage algorithms
increase in complexity as more questions are added,
perhaps making the stages-of-adoption needlessly
complex and reaching a point of diminishing
returns. There is always a concern that more
information than necessary is being collected. On
the other hand, it is important to collect enough
information to distinguish Action from Maintenance.
Our preference has been to request timing of
the two most recent mammograms. In order to be
eligible for Maintenance, the woman must report
two mammograms on her age-recommended interval. Having only one recent mammogram on the
recommended interval, regardless of prior mammograms that were obtained outside of the interval
(e.g. 3 years before the most recent), qualifies the
woman for the Action stage. Future intention is
then combined with the prior behavior to determine
if the woman is classified as Action, Maintenance
or a transitional stage we have called Relapse Risk,
as discussed below. Table III presents the guidelines
for defining the stages-of-adoption.
The preparation stage
One question in applying the TTM to mammography is the ability to distinguish a Preparation stage,
intermediate between Contemplation and Action.
A Preparation stage for mammography might be
difficult to define because there is no completely
definitive action that can be taken until a mammogram is actually scheduled and there is little if
any literature on how women deliberate about
mammography during the 1-2 years between
screening visits or what preparatory actions they
take in advance of an appointment with their
primary care provider. A Preparation stage has
therefore not yet been a part of our extension to
mammography.
In our current study (N = 1323 women aged
50-74, randomly selected from a staff-model HMO
in Rhode Island and southeastern Massachusetts),
only 21% of participants have said that they think
about mammography between regular visits 'during
a normal day at work or home'. In this same
sample, 31% have said that they discussed mammography with someone other than their primary
care provider several times in the 1 year interval
between interviews (unpublished data). Analyses
now underway are examining whether preparation
or early action indicators can be identified with
this and other information from the surveys.
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W.Rakowski et al.
Risk of relapse
The integration of past behavior with future intention for mammography presents a situation that
was not faced with the TTM's application to
smoking cessation. That circumstance is the woman
who would be classified as Action or Maintenance
based on past screening, except for not intending
to have a future mammogram on schedule. In
essence, these women are at risk of lapsing.
This Risk of Relapse classification does not fall
into any of the original groups of the TTM, but
these women do exist An analysis of the 1990
NHIS-HPDP (Rakowski et al, 1993b) found that
18.2% of the sample fell into this risk of lapsing
category. We currently keep a Risk of Relapse
group distinct in the stage-of-adoption algorithm.
Despite having recent screening on schedule, analysis from our in-progress HMO study shows that
these women have a less favorable decisional
balance and processes-of-change than women in
Action or Maintenance (Rakowski et al., 1994).
For example, the Risk of Relapse group had an
average decisional balance of -19.52, compared
to 1.39 and 5.54 for Action and Maintenance,
respectively. Table II also includes these women,
as the group who report a regular schedule, but
have no clear intention to continue. Like the
Relapse group. Risk of Relapse may be more of a
transitional status than a stage-of-adoption. However, it may also designate a state of early retrogression before completely lapsing from screening.
Intervention delivery can therefore benefit from
knowing that a woman who is on schedule does
not intend to keep up.
Sources of ambiguity for staging
One of the requirements of a stage-of-adoption
approach is that the stages be both mutually
exclusive and exhaustive. This can require making
difficult choices in several situations, discussed
below. The specific questions that are used in a
survey will also effect how easily women can be
grouped. Anyone planning to create stages should
map out the algorithm before any data collection.
It is also worth remembering that stages-of-adoption are only one element of the TTM. The
86
objective is not necessarily to have a large number
of stages. For example, computer-based systems,
which generate a personalized report from interview data (Velicer et al., 1993), rely heavily
on the individual's pros, cons and processes-ofchange. It is also possible to supplement knowledge
about a woman's stage-of-adoption with the
specific barriers that she says exist for screening,
as is done with telephone-based counseling (Rimer
et al., 1993). Stage-of-adoption is a starting point;
stage-of-adoption alone is not expected to carry
the full weight of the model.
Boundary time estimates
A potential difficulty exists for staging mammography, and probably for staging other screening
practices as well, due to the interval between
events. That difficulty is a concern about the
precision of recall or future intention, especially
when the past behavior or future intention falls at
the boundaries of the recommended screening
interval. Without specific probing there can be
doubt whether a report of 'a couple of years' is
actually less than or more than 24 months. Similarly, can the staging algorithm strictly require
exactly 1 year (or 2 years) between screening for
women aged 50 and over? Realistically, 'regular'
screenings can be 15 or 26 months apart. However,
at what point is the 'yearly' or 'every other year'
interval sufficiently violated to prohibit placement
in the Maintenance stage? There are no clear
answers for these situations. For example, is a
woman who is now off schedule but says that she
will have a mammogram within the next 15 months
a Contemplator or still in a period of Relapse?
Our coding places her in Relapse. Finally, if an
appointment is made within the proper interval
but the radiology facility cannot schedule the
mammogram in a short time, does staging take
this into consideration?
Age-specific recommendations
Age-specific recommendations have also led to
complexity of the staging algorithm. Under the
1988 consensus, separate tracks were necessary
for women in age groups with every-other-year
Transtheoretica] model and mammography
versus every-year screening recommendations. The
NCI's revision of its guidelines in 1993 may or
may not remove this complexity, based on whether
or not the investigator includes women aged 40-49.
A slightly more subtle issue in staging can be
encountered, even when only women aged 50
and over are participants in a project. That issue
involves women aged 50 to about age 52, and also
women aged 40 to about age 42, due to the fact
that being in Maintenance requires having had two
consecutive mammograms on the age-recommended schedule. Women aged 50-52 may not
have already had two consecutive mammograms,
even if they intend to continue. Should these
women be classified as Action or as Maintenance?
Our current algorithm places these women in
the Action stage. Our rationale first, is that Action
is still a positive classification. Secondly, these
women have to demonstrate that they will maintain
the screening practice over time. Intervention materials and messages for the Action women should
recognize the commitment they have already
shown, compliment their positive intention to continue, and provide support to move into Maintenance.
Providing the guidelines when staging
Should the survey protocol inform women about
the age-recommended guidelines, so that the
woman's report of her screening history is given
with this information in mind? Or, should questions
be asked without having provided such information, so that stage-of-adoption is determined afterthe-fact? Our current practice is not to provide
the screening guidelines in the survey protocol.
Conveying this factual information may bias a
report of future intention—which is an essential
part of the stage algorithm. It also can confound a
survey's subsequent assessment of breast cancer
screening knowledge.
Subjective reports versus objective records
There can be a question as to whether stage-ofadoption should be based on the woman's report
of her screening history or on medical chart data
of her history. Our current practice is to use the
woman's self-report, since we prefer to use her
recall and stated future intention as the basis for
intervention messages.
There may also be circumstances where it is not
advisable to use medical record information. For
example, it is desirable to avoid creating conflict
between the woman and her provider if medical
records do not match her recall. In addition, there
can be recruitment settings where medical record
information may not be complete, such as for new
joiners to an HMO or in emergency rooms. Finally,
if women have more than one primary care provider
(e.g. a gynecologist and an internist), or if they
have mammograms at more than one facility, all
records may not be in one location. In such cases,
only well-funded projects can compile a clinicallybased mammography record.
Using self-report entails some risk of susceptibility to a favorable response set or recall bias due
to telescoping. However, other information from
an interview or questionnaire can also be used for
intervention. This can include responses to the
pros, cons and processes-of-change; and the report
of potential barriers to screening. Women who
have mistakenly recalled their mammogram as
more recent than it was, or who happen to be
purposely reporting their mammography history in
a positive light, still may have several barriers to
screening, negative opinions for decisional balance
or unfavorable processes-of-change.
Waiting for a medical recommendation
Another issue in staging has emerged in regard to
women who report that they will have their next
mammogram 'when my doctor says it is time'. On
the one hand, this is a realistic response because
a physician's advice does carry substantial weight.
On the other hand, the answer also can imply a
reactive approach to having mammography, by not
providing a definite future time for screening. In
the 1990 NHIS-HPDP, 13% of the sample gave
this response and were placed in the Contemplation
stage (Rakowski et al., 1993b). Data from our ongoing HMO study indicate that women aged 5074 who report that their next mammogram will
occur when their physician says it is time have a
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W.Rakowski et al.
negative decisional balance, indicating a tendency
for the cons to outweigh the pros (N = 1323;
mean = -12.79, SD = 17.24; Rakowski et al.,
1994). Research on smoking cessation using the
T l M has not reported decisional balance or processes-of-change for smokers who say they will
consider quitting only when their doctors say to
do so. Investigators may decide to prompt these
women for a definite intended time frame for
screening, in order to place them in a stage.
Alternately, they may opt to keep the women as a
separate group. We arc presently examining their
similarity to the Contemplation and the Risk of
Relapse groups.
Defining the pros, cons and
processes-of-change
It is important to follow established procedures of
item generation and testing, in order to reduce an
initial item pool into final indices with good
measurement properties. There have been other
considerations in developing items for mammography.
Assessing the pros and cons
Types of pros items
Pros items can be worded in several ways. Some
of them can have a basis in knowledge. For
example, a factually sounding pros item could be,
'Mammograms can find breast cancer up to 2 years
before it can be felt by hand*. Other pros items can
sound more attitudinal, such as, 'Having regular
mammograms gives you a feeling of control over
your health'. Still other items can be worded on the
premise that a possible drawback to mammography
will be given less emphasis by women in Action
and Maintenance than women in less committed
stages, for example, 'Any discomfort from a mammogram is worth the benefit I get', or, "The risk
of radiation from regular mammograms is really
quite small'.
The common thread linking these various types
of pros items is that the item must represent a
valid intervention target. In essence, pros items
88
are more than simple attitude statements; they
designate points of view about mammography that
should exist if the person is to eventually move
into Maintenance. There can be items that express
unrealistically positive perceptions about mammography (e.g. 'If I have a mammogram then I
do not need a clinical breast exam'; 'Mammograms
prevent breast cancer'). These are legitimate items
to assess opinions, but they are not acceptable as
pros items because they target benefits that do
not exist
Assessing the cons
As with pros items, cons items can be based on a
benefit of mammography, but the benefit is stated
incorrectly (e.g. 'Mammograms are only useful
for women younger than 60 years old'). A pros
statement could be based on that same benefit, but
would be stated accurately (e.g. 'Mammograms
are effective for women even if they are in their
60s'). Other cons statements can assess opinions
about mammography that have some basis in fact,
but they are written on the assumption that women
in less committed stages will agree more strongly
(e.g. 'Mammograms have high a risk of leading
to unnecessary surgery'; 'Mammograms can be
embarrassing'; 'Mammograms can be very uncomfortable').
One way in which the writing of cons items
differs from pros items is that cons items can span
beliefs of a wider variety, including misperceptions
about mammography that seem quite improbable
based on current knowledge. For example, such a
cons statement might be, 'You are not allowed to
drive a car after having a mammogram' or 'You
can only eat certain types of foods before having
a mammogram'. These can be misperceptions in
the population, but the task for intervention is to
counter a misperception rather than to demonstrate
a factual benefit of mammography. There is no
need to convince women that they can eat a wider
variety of foods if they have mammograms, only
a need to tell women that having mammograms
does not restrict the foods they can eat Because
potential cons about mammography can come from
many sources other than factual literature, writing
Transtheoretical model and mammography
cons items can draw on a wider range of content
than the pros. Pros items cannot make exaggerated
or unrealistic claims for mammography, but it
is possible to have cons items which overstate
negatives or are factually in error.
Comprehensiveness of coverage
A practical consideration with pros and cons items
has to do with how many can realistically be used
in a survey, rather than with the content of the items
themselves. An important distinction is whether the
pros and cons indices are being used as empirical
markers for the strength of a woman's opinions
about mammography (such as by calculating average scores) or whether the items are being used as
individual statements to identify possible barriers
to screening (when persons disagree with a pros
statement or agree with a con). Will there be
enough pros and cons items to cover the full range
of a woman's possible barriers to screening? If the
project is using short pros and cons scales (e.g.
three or four items each, as opposed to six or
seven items each), it is not likely that the items
can cover the full range of possible barriers that
women might state. We still use an open-ended
probe to determine the existence of barriers to
screening.
We also believe that it is important not to
prematurely eliminate items from the pool of pros
and cons. This is a delicate area to address, because
statistical evidence and professional judgment may
need to compromise for at least a little while. From
the standpoint of empirical methods of theory
development, statistical procedures of components
analysis are commonly used to identify pros and
cons 'factors'. Components analysis has been a
standard practice for construct development predating the TTM by many years. Nonetheless, the
risk when using clustering methods is that although
precise definition of a pros (or cons) factor can
occur, the range of content can be narrow relative to
the diversity of pros (or cons) that women express.
Components analysis operates on the presumption that a large percentage of people will have a
sufficiently high covariance on a common set of
statements. This covariance produces evidence of
an underlying 'factor' or latent variable. Pros or
cons that are not frequent in the population, but
still salient for the women who report them, can
be overlooked because they did not 'load' strongly
enough on a component It is possible that certain
general categories of pros (or cons) were not
assessed with enough items to allow a factor
to emerge.
Rather than exclude items which do not load on
a factor in one's first exploratory sample, each
individual item can be examined in relationship to
stages-of-adoption (Rakowski et al., 1992). Items
which do not load on a pros or cons factor can be
retained for further refinement if they show a
relationship with stage. Other items can be written
to assess the concept and be tested in another
sample.
Item-by-item use of TTM pros and cons is not
consistent with the traditional use of the model,
and should not be seen as a sufficient goal in
applying the TTM to mammography or to any
other screening habit. It is always necessary to be
cautious about measurement error influencing the
results of an individual item. However, if the same
item shows a relationship with stage in an expected
direction for two or more samples, and if that
item represents a pro (or con) that women have
expressed anecdotally in other surveys, then it
seems reasonable to retain it for additional
refinement.
Distinct versus overlapping items
It does not seem necessary, in our experience, to
have final pros and cons scales comprised of
'mirror items', stating the same opinion both as a
pro and as a con. However, during item development it is desirable to have the same concept
phrased as a pro and as a con, because one manner
of wording may be easier for respondents to
understand. The item construction leading to our
first set of pilot items took about 4 months, with
up to 10 persons contributing and reviewing the
wording, and yielded in excess of 125 statements.
There presently is not a standard set of pros and
cons statements in the literature. A set of such
items would be a useful resource for comparing
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W.Rakowski et al.
Table IV. Items that may be considered for assessing perceived pros and cons of mammography
Pro/con index and statement wording 1
(A) Pros
Those people who are close to me will benefit if I have a mammogram.
Having a mammogram every year to two will give me a feeling of control over my health.
Regular mammograms give you peace of mind about your health.
Mammograms are necessary even when there is no history of breast problems in a family.
Mammograms are a very routine medical test
Mammograms are most helpful when you have one every year or two.
(B) Cons
If I have a breast exam from a doctor or nurse, I don't need to have a mammogram.
Mammograms have a high chance of leading to breast surgery that is not needed.
Once you have a couple of mammograms that are normal, you don't need to have any more for a few years.
I would probably not have a mammogram unless I had some breast symptoms or discomfort.
If I cat a healthy diet, I will lower my risk of getting cancer far enough that I probably do not need to have a mammogram.
The risk from the radiation of several mammograms over a few years is really quite high.
'Statements are assessed on a five-point Likert-type scale ranging from strongly disagree (1) to strongly agree (5). Higher scores
indicate stronger favorable opinions on the pros and stronger unfavorable opinions on the cons.
data across studies, but it also presumes sufficient
consistency of perceived barriers across localities
and even across subgroups of women (e.g. women
of color, rural versus urban). Table IV lists several
items that have been able to discriminate among
stages-of-adoption, and therefore seem to be worth
serious consideration when developing pros and
cons indices. These items have been selected based
on prior articles (Rakowski et al., 1992, 1993a),
on unpublished data from a sample of 160 AfricanAmerican women and from the baseline survey of
our current HMO study. The coefficient a, internal
consistency reliabilities of these two sets of items,
calculated on our current study's baseline sample
are: pros, a = 0.76; cons, a = 0.73.
There is still ample opportunity to refine the
content of pros and cons scales. The items in Table
IV are offered as a starting point For example,
research looking specifically at subsequent mammograms among women who have had a recent
false positive or false negative could need more
items addressing perceived safety, accuracy and
confidence in one's provider. In our own baseline
survey, we have used two additional items if
women stated that they were other than Caucasian,
non-Hispanic. The items are in Likert-type
response format and refer specifically to the
90
woman's ethnic group: 'Most health professionals
are not prepared to deal with {ethnic group) women'
and, 'The medical system is not set up with the
needs of (ethnic group) women in mind'. These
items were added based on comments from
African-American women suggesting the importance of the interpersonal, affective atmosphere of
health care.
Defining the processes of change
Specifying processes-of-change which might
underlie the adoption of mammography has been
a greater challenge than the pros and cons. Smoking
cessation based on the TTM employs a set of 10
processes of change, which are grouped at a
higher level into experiential-type processes and
behavioral-type processes (Prochaska et al., 1988).
The psychotherapeutic and clinical basis for these
processes has been discussed in detail (e.g. Prochaska and DiClemente, 1982). There is not an
extensive parallel literature on how women prepare
for mammograms or go about dealing with barriers
to obtaining the test. The result is a smaller basis
of information from which to create process scales
than exists for pros and cons.
Our current work has begun with three processof-change indicators. One represents having made
Transtheoretical model and mammography
Table V. Statements comprising processes-of-change scales for mammography
Process-of-change index and statement wording*
(A) Commitment to screening
I am disappointed with myself if I know I am late scheduling a mammogram.
1 think about how much mammograms help women's health.
If the doctor said I did not need a mammogram, I would ask again at another visit.
I arrange my schedule to give me enough time for a mammogram.
I know I feel better about myself if I have a mammogram.
I try to make having a mammogram a regular part of my life.
a = 0.80
(B) Information acquisition, openness and communication
I can talk with at least one other person about mammography.
If I have questions about mammography, I try to get information to answer them.
I give my friends encouragement when they say they are planning to have a mammogram.
Having a mammogram every year or two shows that you are keeping up with the latest advances in health care.
I know that even if a mammogram finds nothing, I am much better off than if I did not have one.
If I hear something unfavorable about mammography, I try to get information and decide for myself.
a - 0.68
(C) Thinking beyond oneself
I am disappointed if my doctor does not remind me to schedule a mammogram.
I talk about mammography with friends.
I sometimes think of ways that could get more women to have mammograms.
I think I could come up with some ideas that could get doctors to recommend mammograms more regularly.
People will be pleased if I have a mammogram.
The more I know about mammography. the more I can help other women who want to know about it.
a = 0.69
"Statements are assessed on a five-point Ljkert-type scale ranging from strongly disagree (I) to strongly agree (5). Higher scores
indicate more favorable opinions on the process of change.
a commitment to regular mammograms, the second
appears to tap a tendency to seek information and
communicate with others, and a third seems to
reflect a readiness to think about mammography
in terms beyond one's own screening status. These
constructs came from unpublished data on 105
women aged 40 and older, recruited from a worksite. Table V shows the items and their coefficient
a's in our HMO sample, where they demonstrate
associations with stages-of-adoption (Rakowski
etal., 1994).
Three is a small number of processes, relative
to the 10 that have been identified for smoking
cessation. In fact, the pool of mammography process items did include all of the concepts found in
the processes-of-change for smoking. (The full set
of items is available upon request.) In our analysis.
however, the behavioral-type processes clustered
on a single component (i.e. Commitment to Screening), while the informational and experiential processes formed two others (i.e. Information
Acquisition, Thinking Beyond Oneself). Although
a limited set, these processes are consistent with
the information- and behavioral-type processes for
smoking.
Nonetheless, additional research on how women
think about mammography and deal with potential
barriers between appointments would be helpful.
In addition, we believe that processes-of-change
for mammography can be expanded to include
women's interaction with the health care system
as a whole (Rakowski et al., 1994). If a woman
does not have regular contact with the health care
system, or if her contacts are primarily for acute
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W.Rakowski et al.
care visits, then it is likely that mammography will
be ignored. In our HMO sample we have found a
four-item cluster representing a tendency to avoid
the health care system whether healthy or ill.
Women in the Precontemplation, Relapse, Risk of
Relapse and Contemplation groups did not differ,
and all exhibited a stronger tendency to avoid
health care than did women in Maintenance. An
intervention directed solely at mammographyspecific issues may not be sufficient to change a
general tendency not to contact the health care
system.
Additional considerations extending the
TTM to mammography
The above discussion has presented major considerations and decisions we have made in adapting
the TTM to mammography. Several other points
also merit some discussion, because they may arise
when applying the model to a new behavior.
Translation of the TTM into intervention
techniques
The TTM specifies key variables for behavior
change, but does not rely on a predetermined
intervention modality (e.g. peer-led groups, videotapes, didactic sessions, brochures and pamphlets,
behavioral contracting). Ideally, data will exist
to indicate which processes-of-change are most
relevant for transition between each adjacent pairing of stages. If such a comprehensive database
exists, as has been the case in smoking cessation,
intervention materials and activities can be directed
at the salient processes-of-change for each stageof-adoption, and at creating the desired balance of
pros versus cons. This integration of stage, pros,
cons and processes is consistent with the traditional
development and application of the TTM. Work
with smoking cessation now uses computer-based,
'expert systems' technology to generate a personalized letter as part of a stage-matched package
(Velicer et al., 1993).
Other investigators may categorize their sample
on the basis of stage of readiness to change, but
design stage-matched interventions that rely less
92
on the results of administering formal pros, cons
and process scales. Computer-generated, personalized letters are not an inherent requirement of the
TTM. Strategies that do not include computergenerated letters may be especially necessary in
settings where data management resources are
limited. Stage-based interventions could center
around resolving practical barriers and knowledge
gaps (e.g. Precontemplators for mammography
might have special difficulty with transportation,
insurance coverage or fear of radiation; Relapse
may be based on unpleasant experiences during
screening; Maintenance women may have to justify
continued screening even if results have been
normal). Interventions may also incorporate testimonials from age and ethnic peers, calendar
markers, and assistance in talking with primary
care providers. A key guideline is that interventions
directed at early stage women should answer basic
questions, provide evidence about the benefits of
screening, and move the woman gradually, while
those directed at women in Action and Maintenance
can reinforce an already established behavior and
positive intention.
The growing popularity of the TTM will
undoubtedly generate many stage-based interventions, but not all of these stage-based interventions
are likely to employ all of the TTM's formal
constructs. Differences between interventions that
use a stage-matched approach, and those that use
both a stage-matched approach and also the TTM's
decision-making constructs are currently difficult
to address. Some on-going investigations in mammography are using different approaches to applying stage-of-adoption constructs. They will provide
valuable experience on the ways in which TTM
variables can be used in behavior change programs.
The number of pro and con indices
Studies using the TTM report a summary decisional
balance score, based on a subtraction of Pros minus
Cons. A single pros index and a single cons index
are used in the calculation, but there is no reason
that a components analysis must yield only one
pros component and one cons component. Our
analyses have not forced a particular number of
Transtheoretical model and mammography
factors to appear in the solution; a pros factor and
a cons factor have emerged naturally. However,
there has been some evidence for additional, but
weaker, components. For example, a set of five
items has emerged which specifically reflect perceived safety of the procedure (coefficient a =
0.67). Larger sets of pros/cons items may yield a
larger number of stable components, and research
may then examine whether these multiple pros and
cons components are part of higher-order factors.
The presence of more than one pro and one con
index is not entirely problematic for applying the
Tl'M to mammography. The number of pros and
cons indices should have no impact on analyses
looking at the association between the individual
pros and cons indices with stages-of-adoption.
However, the calculation of a summary decisional
balance score would be difficult, because it might
not be clear which pro and con indices should
be paired.
Using absolute-value versus T-scores
Raw scores on Tl'M constructs are usually transformed into standardized 7"-score scales with a
mean = 50 and a standard deviation = 10. This
transformation strategy allows comparing results
from study to study, because survey-to-survey
variations in the absolute-value, mean scores arc
eliminated. 7"-scores also allow tracking relative
differences among stages over time, even if the
raw-score mean values change during a period of
years. Finally, 7"-scores permit looking for general
trends across behaviors, such as the pattern of
stage-related differences in pros and cons that
were noted by Prochaska across multiple behaviors
(Prochaska, 1994).
The raw-score values are still important, however. We have observed that many individual
pros, cons and processes statements do not have
extremely negative values even for women in
Precontemplation and Relapse. Instead, mean
values for these two groups can tend more toward
the 'undecided' intermediate range or are only
slightly unfavorable. The association with stagesof-adoption occurs because of the very favorable
reports of women in Action and Maintenance.
Compared to these very positive assessments, all
other groups are 'negative', as their negative Tscore values indicate.
The key point is because T-scores are standardized to the sample mean, the mix of stagesof-adoption in one's sample can influence the
magnitude of apparent positivity and negativity.
For example, if Maintenance women are numerous
in a sample and women in Precontemplation and
Relapse are not numerous, then the very positive
scores of the Maintenance women will disproportionately influence (and inflate) the overall sample
average. Against that standard, even women in
Action may have a decisional balance that is closer
to zero than would be expected based on their
raw-score average. We have encountered this phenomenon in our HMO sample.
The points made above are important for empirical use of the Tl'M. There is also a practical issue
for intervention. That is, health care providers
should be aware that opinions about mammography
can be negative in 7-scores even if the woman is
not clearly opposed to the procedure. Women who
seem simply to be 'non-committal' may have
concerns that need to be addressed. In other words,
even a modest degree of lingering doubts may be
sufficient to interfere with having the exam. Probes
are necessary to find barriers.
The psychological nature of the TTM
The TTM is a psychological model, based heavily
on intentional behavior change. This nature makes
it suitable for activities such as smoking cessation,
exercise, dietary habits, safe sex, weight control
and sun exposure. These health-related behaviors
are amenable to personal control and self-directed
behavior change on the person's own timetable, in
one's own residence. Behavior change can occur
independently of the formal health care system,
and medical technology need not be involved.
In contrast, mammography is inherently linked
to the formal health care system. The application of
the TTM to mammography inevitably encounters
circumstances where access to care is poor and
women have marginal resources (Smith and
Haynes, 1992). Many groups in the population
93
W.Rakowski et al.
have significant difficulty simply meeting demands
of daily life, which can easily make mammography
seem like a luxury item. Access includes transportation, geographic location and time, not only
insurance coverage which covers the cost of the
test. Two questions must be asked: How completely
can a psychologically-based model with several
elements based on deliberate decision-making be
applied to these groups of women? Will adjustments be needed to account for issues of access?
Asking these questions does not imply skepticism about the TTM. As noted earlier, the activities
needed to obtain mammography are volitional in
many aspects. Mammography is a health-related
practice that involves many contextual factors, and
even the best of opinions about mammography can
be thwarted by other forces beyond a woman's
control. For example, women from low socioeconomic status groups who have lapsed away from
screening may still have a positive decisional
balance. Barriers producing Relapse status will be
critical to determine. If resource availability is
problematic for a group of women, strategies for
promoting movement across stages may need to
deal at least as much with providing tangible
assistance as with personal decision making.
Closing comments and future
directions
Research applying the TTM to mammography has
not become as detailed as that conducted with
smoking cessation (e.g. Ahijevych and Wewers,
1992; Prochaska and DiClemente, 1992). However,
a start has been made and the results so far are
promising. Future work can develop several areas.
One area is that item pools may need to be
expanded if mammography studies begin to focus
on individual stages, with a specific type of intervention in mind (e.g. finding Precontemplators to
achieve a first screening; relapse prevention with
women in Maintenance). In-depth study of these
groups of women may reveal more potential barriers and yield insights into decision making that
can be represented in survey items of pros, cons
and processes.
94
Secondly, working with minority populations or
other groups with traditionally low access may
need to add pro and con items that tap personal or
ethnic experiences of discrimination. Mammograms exist in this broader context of interaction
with the health care system. Personal decision
making can be influenced by these historical
factors.
It will also be helpful to investigate how women
think about mammography between appointments
and how they deal with potential barriers. These
data will provide insights into processes-of-change,
and allow operationalizing the Temptations and
Self-Efficacy constructs of the TTM.
Mammography may need to be considered in a
broader context of women's health care. Mammogram-specific intervention may be sufficient if
women are recruited through primary care offices,
as they come in for scheduled visits. If the objective
is to recruit women proactively, however, then
researchers will encounter women who are
avoiding the health care system—not just for
mammography, but as a general characteristic. In
addition, in order to capture Precontemplators, it
may be necessary to package a 'women's health'
program and have mammograms as only one part
of the recruitment message.
It is important to have longitudinal verification
of the stage-of-adoption groups, and also of the
pros, cons and processes. Do these constructs of
the TTM actually predict change in mammography
status over time? So far, data in the literature
have been at the cross-sectional level. It will be
important to understand the natural history of
transitions across stages-of-adoption in the absence
of interventions.
It may be necessary to decide how to accommodate diverse mammography histories into a limited
number of stages. How much historical information
do we need to collect? How do we stage women
whose most recent mammogram was for diagnostic
purposes? How complicated does the stage algorithm have to be? More stages are not necessarily better.
Finally, it is important to remember that this
paper has dealt with applying the TTM to mam-
Transtheoretical model and maramography
mography from the woman's point-of-view. A
separate paper would be needed to apply the TTM
to primary care providers. Our experience is that
the TTM can be used in medical education, and
that stages-of-adoption are well-received. There
are not yet validated scales for assessing providers'
pros, cons and processes-of-change. This remains
an area for development. In the meantime, it is
important not to place exclusive responsibility on
women. Achieving regular mammography is a
joint venture involving the woman, her primary
care provider and the radiology facility. Although
this paper discusses women, they are only one part
of the partnership.
Acknowledgements
Preparation of this manuscript was supported in
part by National Cancer Institute grant R01CA55917. Thanks are extended to Ms Beverly
Enrich for review and comment on earlier drafts
of the manuscript.
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Received on July 18, 1994; accepted on August 17, 1995