HEALTH EDUCATION RESEARCH
Theory & Practice
Vol.12 no.l 1997
Pages 61-75
Condom use adoption and continuation:
a transtheoretical approach
Diane M. Grimley1, Gabrielle E. Prochaska and James O. Prochaska
Abstract
The use of latex condoms can reduce the risks of
sexually transmitted diseases (STDs), including
the human immunodeficiency virus (HIV) that
can lead to the acquired immunodeficiency syndrome (AIDS). Yet, most intervention programs
have demonstrated little effect on overall condom use. The major limitation of many traditional behavioral change programs is that they
are based on an action paradigm which implicitly or explicitly views behavior change as a
dramatic and discrete movement (e.g. going
from 'never' using condoms to 'always' using
condoms). The Transtheoretical Model of
Change (TMC) offers an alternative conceptualization of the structure of change, a stage
paradigm, that defines behavior change as an
incremental process through a series of stages.
This paper offers a summary of how measures
and models of condom use based on the TMC
have been developed and continue to be refined,
offers some preliminary findings with diverse
populations, and describes intervention applications of a stage paradigm approach to condom
use adoption and continuation.
Introduction
An estimated 12 million cases of sexually transmitted diseases (STDs) occur each year in the United
Cancer Prevention Research Center, University of Rhode
Island, Kingston, RI 02881-0808 and •School of Public
Health, Department of Health Behavior, University of
Alabama at Birmingham, Birmingham, AL 35294-0022,
USA
© Oxford University Press
States with serious health consequences for thousands of children and adults (Roper et al., 1993).
Specifically, 86% of all STDs occur among individuals between the ages of 15 and 29 (Centers
for Disease Control and Prevention, 1991). Some
individuals are infected repeatedly with many having more than one infection simultaneously (Aral
and Holmes, 1990). Moreover, sexually active
individuals today have to deal with the real threat
of infection from the human immunodeficiency
virus (HIV) that can lead to the acquired immunodeficiency syndrome (AIDS). The consistent use
of latex condoms can reduce the risks of infection
or transmission of STDs/HTV (Centers for Disease
Control and Prevention, 1988; Coates, 1990; Roper
et al., 1993); yet, most intervention programs have
demonstrated little effect on overall condom use
(Catania et al., 1994). It would appear that traditional behavior change technology is being put to
the scientific test and the limits of this approach
are acutely evident (Chesney, 1993).
The major limitation of traditional behavior
change technology is that it is implicitly or explicitly based on an action paradigm. Action-oriented
approaches to behavior change view condom use
adoption as a dramatic and discrete movement
from 'never' using condoms to 'always' using
condoms. Most intervention programs are
developed for small groups of individuals motivated enough to seek help (Chesney, 1993; Kelly
et al., 1993). The problem is, a number of studies
using different populations (see Table II) point out
that only about one-third of individuals at risk for
STDs/HI V are prepared to take action for consistent
and correct condom use (Prochaska et al., 1990;
Fishbein et al., 1993; Bowen and Trotter, 1995;
61
D. M. Grimley et al.
Galavotti et al, 1995; Grimley et al, 1993a,
1995b). Action-oriented programs are missing twothirds of the population at greatest risk because
these individuals are less likely to respond to
public health messages or to sign up for our
intervention programs.
Many researchers and practitioners in the area
of STD/HIV prevention are beginning to recognize
that a single intervention approach may not be
appropriate for all individuals who are engaging
in unprotected sex. As with other health-related
problems, change agents are shifting the focus of
their efforts toward identifying the 'best fit'
between an individual's characteristics and intervention strategies. The Transtheoretical Model of
Change (TMC; Prochaska and DiClemente, 1983,
1984) offers promise for this endeavor by providing
a framework—or paradigm—for understanding
condom use behavior (Centers for Disease Control
and Prevention, 1992; Galavotti et al, 1995;
Grimley and Lee, 1996; Grimley et al, 1993a,b,
1995a-c, 1996; Prochaska et al, 1990). This paper
offers a summary of how measures and models of
condom use behavior based on the TMC were
developed and continue to be refined. The paper
also provides some preliminary findings with
diverse populations and describes some intervention applications of the stage paradigm approach
to condom use adoption and continuation.
The TMC
The TMC has been postulated as an integrative
and comprehensive model of behavior change.
Research has provided strong support for the
reliability and validity of core constructs from the
model such as the stages of change (McConnaughy
et al, 1983, 1989), the processes of change
(Prochaska et al, 1988), decisional balance
(Prochaska et al, 1994; Velicer et al, 1985)
and self-efficacy (Velicer et al, 1990). Numerous
studies have demonstrated the predictive validity
of the TMC's dynamic variables as compared with
demographic variables such as age, gender or
ethnicity which are imposed on us for the most
part rather than determined by us (Lam et al..
62
1988; Marcus et al, 1992; Wilcox et al, 1985).
At a minimum, these static factors are not under
the potential control of professionals trying to
facilitate change nor are they under the immediate
control of individuals who need to change
(Prochaska, 1989).
Since the TMC is a 'template' of sorts that is
translated or redefined across different healthrelated behaviors (Grimley et al, 1994), the general
constructs of the model (i.e. stages of change,
processes of change, decisional balance and selfefficacy) have been adapted to the measurement
of condom use by making their content specific to
condom use in order to operationalize the constructs. In the initial measurement study conducted
in collaboration with the Centers for Disease Control and Prevention's Division of STD/HTV
(Prochaska et al, 1990), one of the goals was to
investigate the dimensional complexity of condom
use. Specifically, is it necessary to distinguish
between type of sexual partner (primary versus
non-primary) and type of sexual intercourse
(vaginal versus anal) when examining condom
use? Individuals from a community sample at risk
for HTV (e.g. IV drug users, prostitutes, at-risk
street youth, gay or bisexual men, etc.) were
assessed separately on each of the model's key
constructs with both types of partners and types of
sexual activities. Conceptual model testing results
demonstrated that it is necessary to model condom
use behavior separately based on partner type as
well as specific intercourse activities.
Assessing an individual's condom use separately
with primary versus non-primary partners results
in more explained variance with this behavior
as compared with more global measures. The
distinction between partner type is a pervasive
finding that has been replicated with a number of
different populations such as STD clinic patients
(Fishbein et al, 1993), women at high risk for
HIV infection and unintended pregnancy (Galavotti
etal, 1995; Grimley et al, 1992), college students
(Grimley et al, 1995b) and a random state-wide
sample of women (Grimley et al, 1995c). According to Aggleton et al (1994), as the TMC is further
refined for application to HIV/AIDS, 'its use to
Condom use adoption and continuation
guide intervention development and evaluation of
intervention effects is becoming better appreciated'
(p. 343).
Stages of change
A comprehensive model needs to cover the full
course of change, from the time an individual
becomes aware that engaging in unprotected sex
is a problem to the point at which consistent
condom use is maintained. There are many steps
that precede and follow a person taking action
for consistent condom use. In contrast to actionoriented approaches to behavior change, the TMC
offers an alternative conceptualization of the structure of change by defining behavior change as an
incremental and dynamic process. Thus, acquisition
of condom use behavior is the endpoint of a
process that involves motivational and decisionmaking interventions as individuals progress
through a sequence of discrete stages.
Similar to cessation behaviors (e.g. smoking),
acquisition of health-enhancing behaviors such as
condom use involves the progression through five
stages of change of which 'action' is only one.
These stages include: (1) precontemplation, (2)
contemplation, (3) preparation, (4) action and (5)
maintenance.
Sample items employed to assess condom use
with a primary (main) partner are given in Table
I. The following classification scheme results from
the assessment of condom use for individuals
engaging in vaginal intercourse with a main
partner:
(1)
(2)
(3)
Precontemplation includes individuals who
are not currently using condoms 'every time'
for vagina] sex with their main partner and
have no intention to start doing so in the
foreseeable future (i.e. in the next 6 months).
Contemplation includes persons who are not
currently using condoms 'every time' for
vaginal sex with their main partner, but
intend to start doing so sometime in the next
6 months.
Preparation consists of individuals who
intend to start using condoms 'every time'
within the next month and are currently using
Itoble L Algorithm of condom use for vaginal intercourse with
a main partner
Ql. Do you have a main partner of the opposite sex?
1) No (Skip to OTHER Partner)
2) Yes
Q2. When you have vaginal sex with your main partner, how
often do you use a condom?
1) Every time (Go on to Q3)
2) Almost every time (Skip to Q4)
3) Sometimes (Skip to Q4)
4) Almost never (Skip to Q4)
5) Never (Skip to Q4)
Q3. How long have you been using condoms every time you
have vaginal sex with your main partner?
1) Less than 6 months
2) More than 6 months
(Skip to OTHER partner section)
Q4. Axe you seriously thinking about using condoms every
time you have vaginal sex with your main partner in the next
6 months'!
1) No (Skip to OTHER partner section)
2) Yes
Q5. Are you seriously thinking about using condoms every
time you have vaginal sex with your main partner in the next
30 days?
l)No
2) Yes
(Go on to OTHER partner section)
(4)
(5)
condoms 'sometimes' or 'almost always'
with their main partner. The preparation
stage, therefore, consists of both intention
plus some behavioral 'steps' toward consistent condom use.
Action includes individuals who are using
condoms 'every time' for vaginal sex, but
have been doing so for less than 6 months.
Maintenance includes individuals who are
using condoms with their main partner 'every
time' for vaginal sex for more than 6 months.
Progression through the stages is often not linear
because many individuals regress or recycle back
through earlier stages. Individuals may cycle
through the stages several times before they reach
the action criterion of using condoms 'every time'
they engage in intercourse. Within the framework
of the TMC, relapse is viewed as a normal part of
the change process as opposed to a failure. It
63
D. M. Grimley et al.
simply reinforces the notion that change is difficult
and it is unrealistic to expect people to modify
unhealthy behaviors without having any 'slips.'
The stages of change represent a temporal
dimension that provides information regarding
when a particular shift in condom use attitudes,
intention and behaviors may occur. The notion that
behavior change occurs in stages is not unique to
the TMC; similar concepts have been postulated
by others (e.g. Horn, 1976; Weinstein, 1993).
The utility of the stages of change for classifying
individuals on their condom use intentions and
behaviors has been examined with a number of
populations (Prochaska et al., 1990; O'Reilly and
Higgins, 1991; Grimley et al, 1992, 1993a,b,
1995b,c; Fishbein et al, 1993; Galavotti et al,
1995; Grimley and Lee, 1997), supporting the
validity of the construct with this behavior. Table
II shows stage distributions from five independent
samples that classify individuals into the stages of
change for condom use for vaginal intercourse
with the two types of partners. With the exception
of male STD patients, individuals were more likely
to be using condoms with non-primary (other) as
compared with primary (main) partners. In all four
studies, individuals were more resistant to using
condoms with a main partner (i.e. more likely to
be in the precontemplation stage), as compared
with other partners. These observations are consistent with previous research reporting condom use
frequencies (e.g. Rosenberg and Weiner, 1988;
Armstrong et al, 1991; Soskolne et al, 1991;
Dorfman et al, 1992, 1993). Table II also shows
that about half of the college students, as well
as the community high-risk sample, were using
condoms with non-primary partners. All other
stage distributions indicate that 63-92% of the
individuals were not using condoms consistently,
with the majority of non-users being in the two
earlier stages of readiness—precontemplation and
contemplation. These observations point out that
interventions which are based on the assumption
that people are prepared to change (i.e. actionoriented) may not be sensitive to the specific needs
of many people who are not protecting themselves
64
from diseases they can contract from having intercourse with an infected partner.
To date, men and women have been shown to
be evenly distributed across the stages of readiness
for using condoms in a college population (Grimley
et al, 1995b), with a community sample (Prochaska
et al, 1990), and with not-in-treatment IV drug
users and crack cocaine smokers (Bowen and
Trotter, 1995). Sex differences across the stages
of change for using condoms have been reported
in only one study with STD clinic patients. Fishbein
et al (1993) found that men were more likely than
women to be in the precontemplation stage for
using condoms within primary relationships. Male
STD clients remain an understudied population
in urgent need of further intervention research
designed to reduce the adverse health consequences
of sexual risk behaviors.
Ethnicity of individuals as a function of stage
has also been reported in one study. Bowen and
Trotter (1995) found that with main partners, White
participants were more likely to be in the action
stage and less likely to be in the contemplation
stage as compared with African-Americans,
whereas those who were Hispanic were more likely
to be in the contemplation stage than AfricanAmericans. These preliminary findings for ethnic
difference across the stages of change support the
contention that in order to increase adoption and
continuation of condom use, assessments and interventions of specific attitudes sensitive to condom
use across cultural groups are important considerations when targeting condom use (e.g. Amaro,
1995).
Age differences as a significant predictor of
stage is beginning to emerge as a more stable
finding, with younger individuals being in the later
stages of action and maintenance and older persons
being in the earlier stages of precontemplation and
contemplation for consistent condom use (Bowen
and Trotter, 1995; Grimley et al, 1995c). These
observations may reflect the fact that younger
individuals are becoming better educated regarding
their need for safety, may have more positive
attitudes regarding condom use, or perhaps possess
Condom use adoption and continuation
Table II. Percentages of individuals across the stages of change for using condoms with primary versus non-primary partners
Sample
N
Partner type
PC (9b)
C (%)
/>(%)
A (9b)
M (%)
218
193
primary
non-primary
55
21
19
26
—
—
9
9
17
44
268
233
200
primary1
primary
non-primary
43
32
15
18
37
55
25
24
35
8
8
2
6
4
7
primary
non-primaryf
49
22
8
4
31
38
4
9
8
26
233
122
primary
non-primary
46
26
11
12
15
25
7
9
21
27
134
78
primary^
non-primary
23
6
16
19
33
24
13
21
16
30
Community sample1-1'
(Prochaska et al., 1990)
STD clinic patients0
(Fishbein et al., 1993)
men
women
men
IV drug users and crack cocaine smoker*
(Bowen and Trotter, 1995)
166
99
Women at high risk8
(Galavotti et al., 1995)
University students*-*
(Grimley et al., 1995)
•Sex differences across stages were not reported.
'This study was conducted before the consistent emergence of the preparatjon stage; therefore, only four stages were assessed.
c
Percentages were estimated from a graph in Fishbein et al. (1993).
d
Data from women with non-primary partners were too few for meaningful analysis.
e
No significant sex differences were found for stage of change with either primary or non-primary partners.
f
May not equal 100% due to rounding errors.
g
The preparation stage included both intention and a behavioral component (i.e. currently using condoms 'sometimes' or 'almost
always'). Other studies assessed future intention only, without taking any behavioral steps toward consistent condom use into
account.
awareness that they are having more sexual partners
(Bowen and Trotter, 1995).
Processes of change
The second dimension of the model, the processes
of change, provides information on how people
change. The processes represent both covert and
overt activities individuals use to alter their experiences and/or environments in order to affect
behavior, cognitions or relationships. The processes
of change have been found to integrate empirically
within the stage dimension of change (Prochaska
and DiClemente, 1983) showing that these processes are emphasized differentially by individuals
in specific stages of change (Prochaska et al.,
1985; DiClemente et al., 1991).
The processes of change as applied to condom
use acquisition and maintenance have received
little attention by researchers as compared with
other constructs from the model. To date, only
two cross-sectional studies have been conducted
(Grimley et al., 1992, 1994a). Yet, due to the
urgency of assisting individuals at risk for HIV to
adopt condom use, behavior scientists at the Centers for Disease Control and Prevention have
moved forward and are currently conducting an
ongoing intervention study based on general
assumptions of the model regarding process use
65
D. M. Grimley et al.
(Cabral et al., 1996). Although tentative, some
conclusions can be made based on findings from
these preliminary efforts.
Although 10 processes of change have been
found with smoking cessation, 11 processes thus
far have emerged with condom use. Assertiveness
for condom use is the additional process of change
individuals utilize in order to adopt and maintain
consistent condom use (Grimley et al., 1993b;
Bowen and Trotter, 1995). This additional process
of change reflects the interpersonal aspect of sexual
behavior compared with more individual behaviors
like smoking, exercise, etc. When integrated with
the stages, condom use assertiveness increases
almost linearly across the stages with assertiveness
being the lowest in the precontemplation stage and
the highest in the action or maintenance stage.
Consistent
with
model-based
research
(Prochaska et al., 1988), the 11 processes of
change represent two hierarchical factors labeled
'experiential' and 'behavioral'. These two latent
factors include consciousness raising, self-reevaluation, dramatic relief, environmental reevaluation
and social liberation (experiential processes); selfliberation, counter conditioning, stimulus control,
reinforcement management, helping relationships
and assertiveness (behavioral processes). Definitions and sample items for the processes of change
for condom use are shown in Table III.
Some external validity for the measure representing the processes of change has been established
by examining standardized process mean scores'
across the stages of change for using condoms
with main and other partners (Grimley et al., 1992,
1994a). Precontemplators were found to use fewer
processes than those further along in the stages of
change, as the model predicts. The relationships
between the processes and the stage of change for
condom use appear to be similar to other problem
behaviors with process use increasing after the
precontemplation stage. However, preliminary
findings indicate that, contrary to cessation
behaviors where the behavioral processes tend to
level off in the maintenance stage, the behavioral
processes for condom use continue to climb well
into the maintenance stage. Similar findings have
66
emerged with exercise, another acquisition
behavior. These findings suggest that although
individuals in the maintenance stage for condom
use may feel more confident using condoms and
less tempted to engage in unprotected sex, they still
have to work at strengthening their commitment to
using condoms and have to continue to have
condoms with them, so as to maintain behavior
change. Also, women have been found to rely
heavily on the process of helping relationships
with both types of partners, perhaps because
women depend on their partner to 'have' condoms
available for intercourse. Sacco et al. (1993) note
that despite women's more favorable opinions
regarding condom use, they rely on their partners
to buy condoms and make them available during
sex. These observations are supported by the fact
that the only process of change men have been
found to utilize more than women is stimulus
control (e.g. having condoms with them).
Utilization of the experiential processes of
change as applied to condom use acquisition has
also been shown to differ from that found with
cessation behavior. In a process evaluation of an
ongoing intervention study in which stage of
change counseling is provided to high-risk women
(Cabral et al., 1996) more emotional and cognitive
factors were being addressed with women in the
action and maintenance stages for condom use
with primary partners than would be expected
based on the TMC. These preliminary findings
have some support with college women. Grimley
et al. (1994a) found that not only were women
using consciousness raising and dramatic relief
(experiential processes) more than men, they continued to do so in the action and maintenance
stages.
Overall, these findings suggest that, in general,
maintaining condom use within important sexual
relationships may require more continued cognitive/emotional effort than may be required with
non-primary partners or for the maintenance of
other behaviors examined with the model. The fact
that men have the final say regarding whether or
not a condom is used makes consistent condom
use more difficult for women. One implication for
Condom use adoption and continuation
Table III. Titles, definitions and sample items of the processes of change for condom use
Process
Definitions: sample items
Consciousness raising
Increasing information about condom use and awareness regarding one's risk for STDs/HIV
(e.g. 'You remember what people have told you about how condoms can help keep you from
getting STDs/HIV).
Self-reevaluation
Assessing how one feels and thinks about oneself with respect to his/her lack of condom use
(e.g. 'You feel more responsible when you use condoms').
Self-liberation
Choosing and committing to act or belief in one's ability to use condoms (e.g. 'You tell yourself
you can choose to have sex with a condom').
Counter conditioning
Substituting low risk sexual behaviors for high-risk sexual behaviors (e.g. 'When you want to
have sex but don't have a condom, you find other sexual ways to satisfy yourself and your
partner').
Stimulus control
Avoiding people, places, or situations that could result in unprotected sex (e.g. 'You carry
condoms when you go out').
Reinforcement management
Rewarding one's self or being rewarded by others for engaging in safer sex (e.g. 'You reward
yourself when you use condoms for sex').
Helping relationships
Having someone to talk with, share feelings with, and get feedback from regarding one's
experiences with using condoms (e.g. 'You have someone you can count on when you're having
a hard time using condoms').
Dramatic relief
Experiencing and expressing feelings associated with not protecting oneselfs from STDs/HIV
(e.g. 'You get scared when you hear about people getting STDs/HIV because they didn't use
condoms').
Environmental reevaluation
Assessing how one's not using condoms could affect the health and lives of others ('You stop to
think that using a condom protects your partner, as well as yourself).
Social liberation
Changing social norms ('You notice it's getting easier to find partners who don't mind using
condoms').
Assertiveness
Perception of one's ability to assert the use of condoms in a variety of sexual situations ('If a
partner doesn't want to use a condom, you refuse to have sex').
future research is to consider targeting couples as
a unit in order to modify high-risk sexual behaviors.
With smoking cessation, for instance, if one spouse
quits and the other does not, the chances of success
are slim.
Although these examinations of the processes
of change in conjunction with condom use behavior
represent important preparatory efforts, future studies will offer stronger evidence of the measure's
predictive ability. Further measurement development and model testing of the processes of change
for condom use could potentially offer interventionists the ability to conduct much needed process
to outcome evaluations. Such evaluations as Cabral
et fl/.'s (1996), when completed, will help to
determine the extent to which a particular process
needs to be emphasized at a particular stage in
order to predict advancement to the next stage and
to predict relapse.
Decisional balance and self-efficacy
In addition to the stages and the processes of
change, the TMC incorporates two other core
constructs: decisional balance (Velicer et ai, 1985;
Prochaska et al., 1994) based on the decision
making theory of Janis and Mann (1977), and
self-efficacy, which Bandura (1977, 1982, 1986)
considers as the most important construct in social
learning theory.
Decisional balance, simply stated, involves
weighing the advantages (pros) against the disadvantages (cons) of using condoms, e.g. the potential
benefits of using condoms for protection from
67
D. M. Grimley et al.
STDs/HTV infection or transmission must be balanced against the perceived costs. Item content of
the positive aspects of using condoms within the
TMC includes protection from pregnancy and/or
diseases, availability, personal responsibility, low
cost, and protection for a partner, as well as oneself.
An example of a positive item is, 'I would be safer
from disease'.
The content covered for the negative aspects of
using condoms within the TMC includes hassles,
decreased sexual enjoyment, the anticipation of a
partner's disapproval, as well as having to rely on
a partner's cooperation. A sample item of a negative
item is, 'My partner would be angry'. Individuals
are asked to rate 'how important' each statement
is to his or her decision whether or not to use
condoms.
Figure 1 displays the pros and cons of condom
use with main and other partners across their
corresponding stage dimensions for college men
and women (Grimley et al., 1995b). Comparing
individuals across the stages of change on their
pros and cons for using condoms has resulted in
some highly predictable patterns. For example, the
cons of using condoms always outweigh the pros
for individuals in the precontemplation stage. The
opposite is true for those in the maintenance stage.
From precontemplation to contemplation the pros
of using condoms always increase, but there are
no consistent pattern in the cons. The cross-over
of the pros and cons occurs before action takes
place. To date, the functional relationship between
the pros and cons and the stages has been replicated
for condom use adoption and continuation with a
high-risk community sample (Prochaska et al.,
1990), women at risk for HIV infection or transmission (Grimley et al., 1992; Galavotti et al., 1995),
and two independent college samples. (Grimley
et al., 1993a, 1995b).
Although the characteristic cross-over pattern of
the pros and cons of condom use for vaginal
intercourse is similar to that found with at least 12
other health-related behaviors (Prochaska et al.,
1994), the cons of condom use do not decrease
significantly with further movement through the
stages. A less pronounced decrease in the cons
68
Pros and Cons of Condom Use-Main Partner
,
•
•—•
—•—Pros
50
—•—Con*
-—•
1
PC
1
1
j
C
P
A
—i
M
Stages of Change
Pros and Cons of Condom Use-Other Partner
-Pro*
-Cons
C
P
A
M
Stages of Change
Fig. 1. Standardized mean scores (M = 50, SD = 10) for the
pros and cons of condom use with MAIN and OTHER
partners across the five stages of change: precontemplation
(PC), contemplation (Q, preparation (P), action (A) and
maintenance (M).
across the stages of change tends to be more
characteristic of acquisition behaviors (e.g. exercise
adoption), rather than cessation behaviors, because
continual effort is required to maintain the behavior
change (Marcus et al., 1992). The results found
with condom use are more consistent with the
behavioral adoption pattern than with the pattern
of cessation behaviors (Galavotti et al., 1995).
Thus, even if individuals adopt the use of condoms,
the potential for discontinuing condom use remains
high, unless the perceived negative aspects are
diminished. This circumstance may pose a significant challenge to intervention efforts (Galavotti
et al., 1995). Moreover, the cons of condom use
are relatively stable across the stages, particularly
with non-primary partners (Bowen and Trotter,
1995; Galavotti etal., 1995; Grimley etal., 1995b).
Condom use adoption and continuation
Bowen and Trotter (1995) speculate that the
stability of the cons with non-primary partners
may reflect an increased likelihood of relapse as
compared with primary partners because of the
overall smaller change in decisional balance.
Another alternative is that an increase in the pros
of condom use with non-primary partners may be
all that is necessary.
The basic pattern found for the pros and cons of
condom use adoption has implications for applied
interventions. In order to assist individuals in
precontemplation to move to the contemplation
stage, programs must increase people's perceptions
of the benefits of using condoms. These observations point out that the expensive media campaigns
that focus on the negative consequences of
unplanned pregnancies and infection from STDs
might be more effective if public policy permitted
them to stress the advantages and safety of contraceptives as well (Zabin et al., 1993). Information
channels such as sex education courses and public
health messages may also need to be revised (Bryne
et al., 1993). Modification techniques should deal
directly with making the pros of condom use more
salient for individuals (e.g. 'Using condoms tells
your partners that you care about them'). Once a
person has progressed from precontemplation to
the contemplation stage, and is at least thinking
about change, interventions need to focus on
decreasing the cons of condom use which should
lead to further progress from contemplation to
action.
inactive teens reported that they were 'seriously
thinking about having intercourse' for the first time
within the next six months (Grimley and Lee,
1997). Helping teens weigh the subjective advantages and disadvantages of becoming sexually active could assist them in the decision-making
process of whether or not becoming sexually active
is right for them. Such action could potentially
result in the identification of ways in which continued abstinence may be more advantageous and
compatible with an adolescent's personal values
and long-term goals. Individuals who make an
informed decision to engage in intercourse could
be provided with information regarding the importance of using condoms in order to protect oneself
from STDs, as well as unintended pregnancy.
Self-efficacy is defined as the conviction that
one can successfully execute the behavior required
to produce desired outcomes (Bandura, 1982,
1986). Perceived self-efficacy has been shown to
affect whether individuals consider changing their
behavior, the degree of effort they invest in changing, and long-term maintenance of behavioral
change (Velicer et al., 1990; Bandura, 1982, 1986;
O'Leary, 1985). The potential usefulness of individual self-efficacy ratings in predicting health
behavior change has been well documented in such
areas as smoking, weight control, contraception,
alcohol abuse, pain management, recovery from
myocardial infarction and adherence to exercise
programs (Strecher et al., 1986; Marcus et al.,
1992; Velicer et al, 1990).
Males have been found to evaluate the disadvantages of using condoms as higher than the advantages of their use with primary partners (Grimley
et al., 1995b). To date, no sex differences on the
pros and cons for using condoms with non-primary
partners have been found, suggesting that males
and females may share similar attitudes regarding
condom use in less psychologically intimate sexual
situations.
Alternatively, the pros and cons can be integrated
with the stages of readiness for sexual acquisition
behavior among adolescents. In a random sample
of 235 heterosexual female adolescents between
the ages of 15 and 19 years, 18% of the sexually
Within the TMC framework, the construct of
self-efficacy represents an integration of the model
of self-efficacy proposed by Bandura (1982) and
the coping models of relapse and maintenance
described by Shiffman (1986). When examining
condom use adoption, the measure of self-efficacy
assesses the degree of situational pull that might
exist that could induce an individual to choose to
have intercourse without the use of condoms. Some
example items include: 'How confident are you
that you would use a condom ... When you have
been using alcohol or other drugs? When you're
already using another method for birth control?'
The content domain of self-efficacy within the
69
D. M. Grimley et al.
TMC also includes biological and partner-related
issues. Similar to physical urges to smoke experienced with quitting smoking, self-efficacy for using
condoms can be effected by fundamental biological
circumstances such as states of high sexual arousal.
What is unique to condom use, as compared to
other behaviors examined by the model, is the
interpersonal or relational aspect inherent to condom use. Despite the fact that the male condom
was endorsed as the most acceptable method of
contraception by over 2000 women at high risk of
HTV infection (Galavotti etal., 1994), lowest levels
of confidence for using condoms were reported in
situations where the partner might become angry
or upset. Yet, in another study with college-age
men and women (Grimley et al., 1995c), females
reported higher levels of self-efficacy for using
condoms with someone other than a main partner,
whereas no sex differences in efficacy ratings were
found for condom use within primary relationships.
In fact, both college-age men and women and
women at risk for HTV and unintended pregnancy
reported lower levels of confidence for using
condoms when engaging in vaginal intercourse
with primary, as compared with non-primary partners (Galavotti et al., 1995; Grimley et al., 1995b,
1996). These observations suggest that such interpersonal factors as fidelity, commitment and conflict may inhibit the use of condoms within
important intimate relationships, not just for
women (e.g. Morrill, 1994; Amaro, 1995), but for
some men as well.
Figure 2 shows self-efficacy for using condoms
with main and other partners across the five stages
of change. Efficacy scores are the lowest for
individuals in the precontemplation stage and
increase almost linearly for those further along in
the stages of change for condom use (Prochaska
et al., 1990; Galavotti et al, 1995; Grimley et al.,
1995c). Ratings of self-efficacy are not strong
predictors of outcome before an individual reaches
action, but have been shown to be related to
utilization of the processes of change (Prochaska
and DiClemente, 1992).
These findings based on the stages of readiness
and self-efficacy for using condoms are consistent
70
Confidence of Condom Use-Main Partner
-Confidence
PC
C
P
A
M
Confidence of Condom Use-Other Partners)
-Confidence
C
P
Stages of Change
Fig. 2. Standardized mean scores (M = 50, SD = 10) for selfefficacy for condom use with MAIN and OTHER partners across
the five stages of change: precontemplation (PC), contemplation
(C), preparation (P), action (A) and maintenance (M).
with the basic premise of the Information-Motivation-Behavioral Skills (1MB) model of AIDSpreventive behaviors postulated by Fisher and
Fisher (1992) and Fisher et al. (1994). The 1MB
model assumes that different levels of information
and motivation may characterize individuals at
different stages of the change process. Fisher et al.
(1994) contend that individuals in the precontemplation stage may be informed about STDs/HIV,
but are not yet motivated to change their unsafe
sexual practices; those contemplating change may
be informed and somewhat motivated but may still
not possess the requisite behavioral skills necessary
to engage in consistent condom use; yet, individuals
actually enacting change must generally possess the
requisite information, motivation and behavioral
skills associated with condom use.
Condom use adoption and continuation
Putting theory into practice
Nearly 15 years of research on how people change
on their own and in intervention studies has lead
to the development of a TMC expert system
intervention (Prochaska et al., 1993; Velicer et al.,
1993). Expert systems are computerized interventions that are based on a person's own responses
to questionnaires that are scored and then interpreted by expert computer technology which then
generates a unique report. The reports include
feedback on: the individual's stage of change,
decisional balance regarding the pros and cons,
the processes of change that the individual may be
underutilizing, overutilizing or is utilizing appropriately, and self-efficacy across a variety of situations, and points out potentially problematic
situations that need to be targeted to prevent
relapse.
At baseline, each person's scores on all TMC
variables are compared to a normative data base
(data from individuals from the same population;
same age group, etc., who have successfully progressed through the stages for a specific behavior).
At follow-up, ipsative feedback (compared to self
over time) is also provided on TMC variables
that are most important for progressing from one
particular stage to the next. Expert systems are
theory driven and lead to more scientific and
accurate diagnoses of specific problem behaviors.
It is important to emphasize that each report
generated by the system is truly matched to the
individual based on his or her responses to the
TMC assessment instrument.
Two systems are currently being developed in
the area of high-risk sexual behavior change. The
first is a multi-media expert system that targets
condom use with inner city females 14-17 years
old. The overall focus of the study is to prevent
cervical cancer and will be provided in several
family planning clinics in the Philadelphia area.
Females will be randomly assigned to the TMC
condition or the usual care condition. Participants
in the TMC intervention will sit at a computer and
answer questions by clicking on a 'mouse' in
regards to condom use intention and behaviors.
Each assessment is separated into distinct sections
based on the model's constructs. After each section,
participants will receive immediate, personalized
feedback based on their individual responses
regarding their current stage of change for using
condoms; the change processes which they may
not be using, or perhaps using too much; where
they stand in the decision-making process for using
condoms based on their pros and cons scores; what
ideas they need to think more about in order to
motivate them to move to the next stage of change;
and alerts them to specific sexual situations they
will need to avoid to maintain consistent condom
use. This feedback will appear 'on screen' and
win also be vocalized through the use of a headset.
At the end of each session, each participant and
her assigned counselor will be provided with a
computer generated printed report reflecting the
key issues that need to be addressed in order to
promote advancement tiirough the stages. Counselors will then reinforce the computerized feedback with each individual. Teens in the usual
care condition will receive generic feedback plus
counselor support.
The second system is home-based as opposed
to the above clinic-based intervention. This expert
system is being designed to increase compliance
with oral contraceptive use and to promote condom
use with women whose sexual behavior, or their
partner's behavior, may place them at risk for
STDs.
This expert system will involve a pencil-andpaper survey that is filled out by women when a
prescription for oral contraceptives is given, or
completed at home and returned in a postage-paid
envelope. Proactive phone calls will be made to
women who do not return the completed questionnaire with 2 weeks in order to have each study
participant's data. Survey's will then be scanned
into a database and a unique report generated,
which will then be mailed out to each participant as
quickly as possible. In addition to giving feedback
based on all constructs of the model regarding
adherence to pill-taking directions, women who
are having intercourse with more than one partner,
71
D. M. Grimley et al.
or with a high-risk partner, will receive feedback
on the importance of using condoms along with the
pill for disease protection. Such stage-matched
interventions have the ability to reach the vast
majority of populations at risk by providing interventions which are sensitive to the specific needs
of individuals in the earlier stages and not just
those who are motivated to change. When used in
combination with proactive recruitment methods,
stage-matched computer-based expert systems can
provide effective standardized, individualized, and
interactive interventions while impacting large percentages of the population (Velicer and DiClemente, 1993).
A stage-based intervention2 is currently being
employed with women at high-risk for both unintended pregnancy and HTV infection or transmission (Cabral et al., 1996) funded by the Division
of Reproductive Health at the Centers for Disease
Control and Prevention. This comprehensive AIDS
and reproductive health education study (Project
CARES) has generated a guide based on the TMC
for advocates to utilize when counseling women
(Project CARES: Advocates' Guide to Stage of
Change Counseling, January 1994). The intervention study focuses on women who are less likely
to come into family planning centers and have
been recruited through drug treatment centers,
homeless shelters, an HTV clinic, and street outreach in high-risk neighborhoods. Participants are
assessed on their readiness to change by paraprofessional peer advocates who assist women to engage
in stage-based strategies in order to facilitate progress toward action for the consistent use of
condoms and other contraceptives. This type of
stage-based guide has recently been developed for
utilization with heterosexual men who are STD
patients in order to increase condom use (Grimley
and Prochaska, 1996).
Another potential application of the TMC when
modifying STD/HIV risk behaviors could be to
utilize community outreach workers or street educators who have already developed credibility
and rapport with community members. Outreach
workers familiar with the TMC can have a much
greater impact on the overall community by enab-
72
ling them to reach and assist large numbers of
individuals who are in the earlier stages of change
to progress more quickly through the stages. In
addition, they possess knowledge of the cultural
barriers that may exist in their particular community and can make referrals to other community
organizations when needed.
Conclusion
Many existing behavior change programs offer the
best action-oriented strategies available, but seem
to be failing. This is due, in part, to providing
'one-size-fits-air interventions without considering
a person's readiness to follow such advice (e.g.
Prochaska, 1994b). Interventions targeting condom
use adoption and continuation based on the TMC
have the potential of combining not only the
individualization and intensity of the clinical intervention, but also the high participation rates of the
public health approach, resulting in high-impact
interventions. When we integrate individual and
public health approaches, the treatment goal must
be to accelerate stage movement to action prior
to providing action-oriented treatments (Abrams,
1993). In other words, we need to move away
from the old action-oriented paradigm of behavior
change to a stage-matched approach if we are to
meet the needs of all individuals at risk for STDs/
HIV and not just the relatively small percentage
of individuals prepared to take action.
Acknowledgements
This paper was supported in part by grants
CA27821 and CA50087 from the National Cancer
Institute and CSA-92-109 from the Centers for
Disease Control and Prevention, and funding provided from Ortho Pharmaceutical, Inc.
Notes
1. In order to provide a standard metric, data on all TMC
constructs are converted from raw scores to 7"-scores (M =
50, SD = 10) when integrated with the stages of change.
2. Stage-based interventions are designed based on a person's
current stage of change only.
Condom use adoption and continuation
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