ORIGINAL ARTICLE
Adenotonsillectomy or Watchful Waiting in Patients
With Mild to Moderate Symptoms of Throat
Infections or Adenotonsillar Hypertrophy
A Randomized Comparison of Costs and Effects
Erik Buskens, MD, PhD; Birgit van Staaij, MD, PhD; Jet van den Akker, MD, PhD;
Arno W. Hoes, MD, PhD; Anne G. M. Schilder, MD, PhD
Objective: To evaluate the cost-effectiveness of adeno-
tonsillectomy compared with watchful waiting in Dutch
children.
Design: Economic evaluation along with an open, randomized, controlled trial.
Setting: Multicenter, including 21 general and 3 university hospitals in the Netherlands.
Participants: Three hundred children aged 2 to 8 years
were selected for adenotonsillectomy according to routine medical practice. Excluded were children who had
frequent throat infections and those with suspected obstructive sleep apnea.
Main Outcome Measures: Incremental costeffectiveness in terms of costs per episode of fever, throat
infection, and upper respiratory tract infection avoided.
of 2002 when $0.95=€100) and €551 in the watchful waiting group (46% increase). During a median follow-up of
22 months, surgery compared with watchful waiting reduced the number of episodes of fever and throat infections by 0.21 per person-year (95% confidence interval,
−0.12 to 0.54 and 0.06 to 0.36, respectively) and upper
respiratory tract infections by 0.53 (95% confidence interval, 0.08 to 0.97) episodes. The incremental costs per
episode avoided were €1136, €1187, and €465, respectively.
Conclusions: In children undergoing adenotonsillectomy because of mild to moderate symptoms of throat
infections or adenotonsillar hypertrophy, surgery resulted in a significant increase in costs without realizing
relevant clinical benefit. Subgroups of children in whom
surgery would be cost-effective may be identified in further research.
Trial Registration: isrctn.org Identifier:
Results: Annual costs incurred in the adenotonsillec-
tomy group were €803 (the average exchange rate for the
US dollar in 2002 was $1.00=€1.1, except toward the end
Author Affiliations:
Julius Center for Health
Sciences and Primary Care
(Drs Buskens, van Staaij, and
Hoes) and Department of
Otorhinolaryngology,
Wilhelmina Children’s Hospital
(Drs van den Akker and
Schilder), University Medical
Center Utrecht, Utrecht; and
Department of Epidemiology,
University Medical Center
Groningen, University of
Groningen, Groningen
(Dr Buskens), the Netherlands.
ISRCTN04973569
Arch Otolaryngol Head Neck Surg. 2007;133(11):1083-1088
I
N WESTERN COUNTRIES, TONSILlectomy with or without adenoidectomy is among the most frequently performed surgical
procedures in children. However, as may be inferred from the wide range
of surgical incidences observed between
countries, the indications and expected benefits are debated. In 1998, the Netherlands ranked high, with 115 adenotonsillectomies per 10 000 children compared
with 65 per 10 000 children in England and
50 per 10 000 children in the United States.1
Preference for antibiotic therapy vs surgical management of upper respiratory tract
infections may explain some of this variation.2 However, the lack of sound evidence about the balance between costs and
effects of adenotonsillectomy compared
(REPRINTED) ARCH OTOLARYNGOL HEAD NECK SURG/ VOL 133 (NO. 11), NOV 2007
1083
with a conservative approach in children
with mild to moderate symptoms of throat
infections or adenotonsillar hypertrophy is
also important.3 Historically, the reluctance of Dutch general practitioners to prescribe antibiotic therapy and the national
notion that adenotonsillectomy may be considered minor surgery seems to have resulted in rather liberal indications for surgical intervention. Clearly, the considerable
variation in practice may reflect either overtreatment or undertreatment, that is, suboptimal use of scarce health care resources. In the Netherlands, some 35% of
children undergoing adenotonsillectomy
have frequent throat infections (ie, ⱖ7 episodes in the previous year, ⱖ5 episodes in
each of the previous 2 years, or ⱖ3 episodes in each of the previous 3 years) or
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obstructive sleep apnea. Conversely, the remaining 65%
undergoing surgery have less frequent throat infections,
milder symptoms of adenotonsillar hypertrophy, or other
indications such as recurrent upper respiratory tract infections.4 Frequent throat infections and obstructive sleep
apnea are generally recognized indications for tonsillectomy or adenotonsillectomy.5,6 However, in most children operated on in the Netherlands, the benefits are less
clear.7,8 To resolve this issue, a randomized trial was
conducted to compare the balance between costs and effects of adenotonsillectomy and watchful waiting in children with mild to moderate symptoms of throat infections, upper respiratory tract infections, or adenotonsillar
hypertrophy.
METHODS
The design of the study has previously been reported.8 In brief,
an open multicenter, randomized, controlled trial was conducted in 21 general hospitals and 3 university hospitals in the
Netherlands between March 18, 2000, and February 28, 2003.
Before enrollment, information about the indication to perform
adenotonsillectomy was recorded for every child aged 2 to 8 years.
The indications included recurrent throat infections (ⱖ3/y) or
other indications such as symptoms of obstruction or recurrent
upper respiratory tract infections. Children with a history of frequent throat infections9 and those with a Brouilette obstructive
sleep apnea score higher than 3.5, reflecting a high suggestion
of obstructive sleep apnea,10 were excluded because in children,
these indications are not disputed. Patients with Down syndrome, craniofacial malformations, and documented immunodeficiency other than IgA or IgG2 were also excluded from this
study.
After obtaining informed consent from the parents, the children were randomly assigned to prompt adenotonsillectomy
(within 6 weeks) or watchful waiting. During follow-up, additional interventions were allowed if deemed necessary. This
was left to the discretion of the attending surgeon.
The study was undertaken in accord with the European
statement for good clinical practice, which includes the provisions of the Declaration of Helsinki of 2000.11 The medical
ethics committees of all participating hospitals approved the
study protocol.
FOLLOW-UP
During the study, parents kept a diary of upper respiratory tract
symptoms in their child. Sore throat, pain or difficulty with swallowing, cough, rhinorrhea, earache, and otorrhea were recorded. Furthermore, the child’s temperature was measured daily
with a validated infrared tympanic membrane thermometer.12
To prevent information bias, an inbuilt device stored the date
and first temperature measurement for each day. Both diary and
thermometer data were collected by study physicians (B.v.S.
and J.v.d.A.) during scheduled follow-up visits at 3, 6, 12, 18,
and 24 months.
fever (body temperature ⬍38.0°C) for at least 1 day. A new episode of fever was recorded after a fever-free interval of at least
7 days.
Secondary measures of clinical effectiveness were throat and
upper respiratory tract infections. A throat infection was defined as sore throat, pain or difficulty with swallowing, or both
as indicated in the diary, in combination with fever measured
with the tympanic thermometer. An upper respiratory tract infection was defined as including 1 or more of the following symptoms: cough, earache, sore throat, rhinorrhea, pain or difficulty with swallowing, and otorrhea with or without fever.
Symptoms of sore throat and upper respiratory tract infections occurring immediately after adenotonsillectomy were included in the outcomes.
In parallel with the clinical study, annual costs in euros (€)
were estimated at the patient level for 2002. (The average exchange rate for the US dollar in 2002 was $1.00= €1.1, except
toward the end of 2002 when $0.95=€100.) Resource use such
as over-the-counter drug use and outpatient visits were recorded in the diaries, as were out-of-pocket expenses such as
babysitters and travel expenses. The study physician verified
diary entries during the follow-up visits and recorded interventions such as adenoidectomy or placement of tympanostomy tubes. The scheduled visits by the research physician were
excluded from the cost analyses.
Costs were estimated from a societal perspective and retrieved from available sources when possible. When unavailable, unit costs were estimated in a separate bottom-up costing study. The costs of adenotonsillectomy, adenoidectomy, and
placement of tympanostomy tubes as well as those associated
with surgical complications were calculated based on resource use and personnel input as estimated in 7 participating
hospitals. The costs associated with surgical complications were
similarly estimated.
Costs of medication, including antibiotics, were derived
from the Dutch Formulary13 and increased with a pharmacist
fee. Costs of diagnostic tests were derived from the Dutch Diagnostic Formulary14 and, when relevant, increased with a
technician charge. Costs of over-the-counter drugs and alternative medicines were based on average retail prices. Costs of
consultation of a general practitioner or medical specialist or
of other procedures and hospitalizations were based on current Dutch guidelines for pharmacoeconomic evaluation15 or
charges if no other estimates were available. Indirect costs to
society associated with leave of absence were estimated using
the friction cost method.16
Incremental costs per episode of fever, throat infection, and
upper respiratory tract infection avoided were calculated. Incremental cost-effectiveness ratios were calculated by dividing the estimated differences in yearly cost rates by the differences in effect rates, that is, episodes avoided per person-year.
For all analyses, only a short time horizon was used and, therefore, no time preference or discount rate was considered. Uncertainty was addressed by means of bootstrapping.17 The original trial data were used to replicate the trial 1000 times using
a random sampler with replacement. Subsequently, the incremental costs and effects were estimated and plotted for each
replicate, yielding a cost-effectiveness plane.
OUTCOME MEASURES
STATISTICAL ANALYSIS
The primary measure of clinical effectiveness used for the economic evaluation was the number of episodes of fever avoided
per person-year. Fever was defined as a body temperature of
38.0°C or higher as measured by the infrared tympanic thermometer for at least 1 day. Fever was measured in number of
episodes and days. An episode ended when a child was free from
Calculations of group size were based on a clinically relevant
reduction of 25% in episodes of fever and throat infections after adenotonsillectomy. Assuming a mean (±SD) baseline incidence of 4 (±2) fever episodes and 4 (±2) throat infections
per year, and taking ␣ =0.05 (2-tailed) and a power of 0.80, at
least 104 children were required in each arm of the trial.
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Table 1. Baseline Demographic and Clinical Characteristics
in 300 Participants According to Treatment Allocation a
Adenotonsillectomy
Group
(n = 151)
Characteristic
Male sex
Age, mean (SD), mo
Indication for surgery as
indicated by local
ENT surgeon
Recurrent throat
infections
Other indications
Throat infections in
the previous year,
mean (range), No. b
Duration of throat infections,
median (range), mo b
Episodes of rhinorrhea or
cough in the previous
year, median (range), No.
OSA score, median (range) c
Previous ENT surgery
Adenoidectomy
Placement of
tympanostomy tubes
81 (53.6)
54 (17.0)
Watchful-Waiting
Group
(n = 149)
66 (44.3)
54 (16.2)
76 (50.3)
67 (45.0)
73 (48.3)
3 (0 to 6)
82 (55.0)
3 (0 to 6)
13 (0 to 50)
12 (0 to 60)
12 (0 to 24)
10 (0 to 24)
−1.7 (−3.83 to 2.55) −1.7 (−3.83 to 2.56)
35 (23.2)
19 (12.6)
33 (22.1)
17 (11.4)
Abbreviations: ENT, ear, nose, and throat; OSA, obstructive sleep apnea.
a Data are given as number of participants (percentage) unless otherwise
indicated.
b Only for 143 children selected because of recurrent throat infections.
c Brouilette Obstructive Sleep Apnea Score: 1.42⫻Difficulty
breathing⫹1.41⫻Apnea⫹0.71⫻Snoring−3.83. Range, −3.83 to ⫹3.5. Score
greater than 3.5 is highly predictive of OSA; score between −1 and 3.5 indicates
possible OSA; and score below −1, no OSA.
The measures of clinical effect were calculated as incidence rate difference per person-year with 95% confidence interval. Overall cost rates were compared between the randomized groups. When relevant, differences were calculated,
inclusive of 95% confidence intervals, using bootstrap replications. All analyses, inclusive of the economic evaluation, were
performed on the basis of intention to treat.
Table 2. Resources Used and Cost Estimates for 2002
Resources
Cost
Estimate, € a
Source
320.84
365.93
683.56
Cost study
Cost study
Cost study
361.32
581.39
724.04
Cost study
Cost study
Cost study
362.72
1212.55
Cost study
Cost study
45.09
Cost study
45.09
240.00
120.00
18.32
20.04
Guideline
Guideline
Guideline
Guideline
Guideline
21.66
Guideline
Adenoidectomy
Adenoidectomy plus myringotomy
Adenoidectomy plus placement of
tympanostomy tubes
Adenotonsillectomy
Adenotonsillectomy plus myringotomy
Adenotonsillectomy plus placement of
tympanostomy tubes
Placement of tympanostomy tubes
Repeat operation because of primary
hemorrhage
Consultation with otorhinolaryngologist
because of minor hemorrhage
Consultation with otorhinolaryngologist
Hospitalization per day
Day care
Consultation with general practitioner
Consultation with paramedical
professional
Leave of absence, per hour based on
friction costs
Abbreviation: Guideline, Dutch guidelines for pharmacoeconomic
research.15
a The average exchange rate for the US dollar in 2002 was $1.00 equaled
€1.1, except toward the end of 2002 when $0.95 equaled €100.
eration. Median follow-up was similar in both groups:
22.0 months (range, 0.4-27.1 months) in the adenotonsillectomy group and 22.4 months (range, 1.5-26.5
months) in the watchful-waiting group.
CLINICAL EFFECTIVENESS
Children in the adenotonsillectomy group experienced
0.21 fewer episodes of fever and throat infections per person-year (95% confidence interval, −0.12 to 0.54 and 0.06
to 0.36, respectively) and 0.53 fewer upper respiratory
tract infections (95% confidence interval, 0.08 to 0.97).
RESULTS
COMPLICATIONS OF SURGERY
PATIENTS
Of the 195 children (145 in the adenotonsillectomy
group and 50 in the watchful-waiting group) who
underwent adenotonsillectomy, 12 (6%) experienced
surgery-related complications. Seven children had a primary hemorrhage, that is, occurring within 24 hours
after intervention. Two of the 195 (1%) were managed
surgically and 5 (3%) nonsurgically; 3 children (2%)
were admitted for observation for 1 night. Five children
(3%) had postoperative nausea, which was managed
with antiemetic medication and intravenous fluid
administration.
Between March 1, 2000, and August 31, 2002, 300 children were enrolled; 151 were allocated to adenotonsillectomy and 149 to watchful waiting. Baseline characteristics did not differ between the adenotonsillectomy
and watchful-waiting groups; mean age of the children
was 54 months and the median number of throat infections in the previous year was 3 episodes in both groups
(Table 1). Overall, 43 children were lost to follow-up,
18 from the adenotonsillectomy group and 25 from the
watchful-waiting group. Reasons were nonmedical in 36
children (parents moved to another town or considered
participation too time-consuming), serious comorbidity in 1, or unknown in 6. In addition, 50 children allocated to the watchful-waiting group underwent adenotonsillectomy during follow-up and 7 children allocated
to the adenotonsillectomy group did not undergo the op-
COSTS
A detailed overview of the most relevant cost estimates
is given in Table 2. Overall, patients in the adenotonsillectomy group incurred €803 per person-year, on average, whereas patients in the watchful-waiting group in-
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COST-EFFECTIVENESS
A
Costs, difference,
600
400
200
87%
0
–2
–1
0
1
Fever Episodes, Difference
B
600
Costs, difference,
400
COMMENT
200
99%
0
–1
–½
0
½
Throat Infections, Difference
C
600
Costs, difference,
400
200
93%
0
–2
The balance between costs and effects, inclusive of uncertainty, was assessed by head-to-head comparison of costs
and effects for the original trial data and for the 1000 bootstrap replicates of the trial. The incremental costs per episode of fever, throat infection, and upper respiratory tract
infection avoided were €1136, €1187, and €465, respectively. The bootstrap replications yielded similar results.
Incremental costs (y-axis) and effects (x-axis) for the
adenotonsillectomy strategy as compared with the watchful-waiting strategy of each of the replicates are shown
in the Figure for episodes of fever, throat infections, and
upper respiratory tract infections, respectively.
The Figure also shows the percentage of bootstrap estimates when adenotonsillectomy resulted in a lower disease episode rate than watchful waiting. For episodes of
fever, 87% of the bootstrap replicates indicate an advantage of adenotonsillectomy over watchful waiting; for
throat infections, 99%; and for upper respiratory tract infections, 93%.
–1
0
1
Upper Respiratory Infections, Difference
Figure. Incremental costs and effects for adenotonsillectomy compared with
watchful waiting for episodes of fever (A), throat infections (B), and upper
respiratory tract infections (C). The percentage in the lower left corner
indicates the proportion of bootstrap replicates in which adenotonsillectomy
vs watchful waiting yielded a positive health effect; that is, the percentage
reflects the certainty with which a positive effect may be expected.
curred €551 per person-year (46% increase). As for
uncertainty, bootstrap analyses indicated that adenotonsillectomy increases overall costs with 100% certainty
(Figure).
Only costs associated with general practitioner visits
and use of over-the-counter drugs were decreased by adenotonsillectomy, by €7 and €4, respectively. Other costs
did not differ or were higher in the adenotonsillectomy
group than in the watchful-waiting group.
In children selected to undergo adenotonsillectomy because of mild to moderate symptoms of throat infections or adenotonsillar hypertrophy, surgery, in comparison with watchful waiting, resulted in an overall
increase in costs of 47%, that is, more than €250-cost increase per person-year. This increase was not counterbalanced by a clinically relevant reduction in the number of episodes of fever, throat infections, or upper
respiratory tract infections. Although slightly better outcomes were observed with considerable certainty (85%99%), the net effect in terms of discomfort as measured
in days or episodes of disease avoided may be negligible. Effects in terms of quality of life and especially quality-adjusted life-years are not reported herein because the
primary outcome indicated minor health effects.8 We previously reported a significant but clinically irrelevant shortterm advantage in health-related quality of life for adenotonsillectomy over watchful waiting, and identical
health-related quality of life at 24 months.8 Thus, if the
difference in costs were balanced against a very small difference in quality-adjusted survival time, the incremental cost-effectiveness ratio would be less favorable.
Overall, the balance between costs and effects in this
population seemed unfavorable for adenotonsillectomy, with incremental cost-effectiveness ratios in excess of €465 per disease episode averted. Note that this
estimate includes societal costs such as parental leave of
absence associated with their child’s illness. Had these
costs been left out of the equation, the figures would be
even somewhat less favorable. With time, the child’s immune system matures and the difference in adverse episodes disappears. Thus, the initial cost increment in the
adenotonsillectomy group will never be counterbalanced by a continued positive health effect.
To our knowledge, this is the first elaborate economic evaluation along with a randomized clinical trial
on adenotonsillectomy in children, yielding informa-
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tion readily applicable in policy decisions. However, to
fully appreciate the results of our study, certain aspects
must be discussed in more detail.
Children selected for adenotonsillectomy because of
frequent throat infections or obstructive sleep apnea were
excluded from this trial because these indications are not
disputed. Generalization of our results, therefore, may
be limited to children with milder symptoms. For children with frequent throat infections, no data on costeffectiveness of surgical interventions are available as yet.
In children with obstructive sleep apnea syndrome, adenotonsillectomy reduces health care use.18 Clearly, a direct comparison with results obtained in other randomized trials evaluating adenotonsillectomy remains
problematic.7 Owing to variable inclusion criteria, outcome measures, duration of follow-up, and other study
characteristics, quite different results may be anticipated. However, the effects of adenotonsillectomy were
not that much more favorable in the subgroups of children with more severe symptoms. Overall, results of all
previous trials show that about 1 or 2 episodes per year
may be avoided with adenotonsillectomy.7 It would seem
that inasmuch as the initial costs associated with an operation are similar, the likelihood of attaining an acceptable incremental cost-effectiveness ratio is questionable. Accordingly, cost-effectiveness studies in this field
seem to be indicated as well.
Another issue that requires further elaboration is that
50 children (34%) crossed over from the watchfulwaiting group to the surgery group during follow-up. Inappropriate handling of these data could have led to bias;
that is, per protocol analyses, either excluding children
who changed treatment group or analyzing children on
the basis of the time spent in any treatment arm might
have resulted in underestimation or overestimation of the
treatment effect. To prevent such bias, and considering
our intention to compare strategies as observed in daily
practice rather than to perform a strictly controlled comparison of adenotonsillectomy vs watchful waiting, we
performed an intention-to-treat analysis. During followup, subsequent episodes of disease in children enrolled
in the watchful-waiting arm apparently urged a considerable percentage of parents and physicians to decide on
surgery. This may be a consequence of the Dutch setting, in which parents and physicians apparently had positive expectations about the benefits of adenotonsillectomy. Scrutiny of the baseline characteristics revealed that
initially all children, that is, those who crossed over to
the other treatment arm and those who did not, were similar. Also, note that a crossover added to the costs but also
may have had an effect on the net effects because surgery is associated with discomfort as well. Overall, we
believe that a possible minor short-term effect on perceived quality of life is irrelevant in the perspective of
identical longer-term outcomes.
For episodes of fever, however, there were no differences because, in terms of less bias-prone parameters and
outcome parameters, there were no differences between
children who crossed over and those who did not. Thus,
our results stand as they are.
A final point about the generalizability of our results
is related to the adenotonsillectomy technique gener-
ally used in the Netherlands, that is, the Sluder guillotine technique.19 We noted that, in this trial population,
4% of the patients had a primary hemorrhage, of whom
1% were returned to the operating room. This may seem
fairly high compared with some other series. The technique is usually combined with inhalation anesthesia with
sevoflurane administered through a face mask and does
not require endotracheal intubation. This combination
of surgical technique and anesthetic takes only about 15
minutes from entry to the operating room to transfer to
the recovery room. Almost all procedures are performed in an outpatient setting. This has considerable
consequences for the costs of the procedure. Compared
with other Western countries, our cost estimates may be
low; the incremental cost-effectiveness ratios based on
Dutch cost estimates seem too favorable. In other settings, the cost-effectiveness would be further offset by
more costly procedures.
CONCLUSIONS
In most Dutch children undergoing adenotonsillectomy because of mild to moderate tonsillar disorders, surgery resulted in a significant increase in costs without
realizing relevant clinical benefit. Additional research is
needed to identify subgroups of children in whom surgery might be cost effective.
Submitted for Publication: August 30, 2006; final revision received January 1, 2007; accepted February 11, 2007.
Correspondence: Erik Buskens, MD, PhD, Department
of Epidemiology, University Medical Center Groningen, University of Groningen, Room 3.E.15, PO Box
30.001, 9700 RB Groningen, the Netherlands (e.buskens
@epi.umcg.nl).
Author Contributions: Dr Buskens had full access to all
of the data in the study and takes responsibility for the
integrity of the data and the accuracy of the data analysis. Study concept and design: Buskens, van Staaij, van den
Akker, Hoes, and Schilder. Acquisition of data: van Staaij
and van den Akker. Analysis and interpretation of data:
Buskens, van Staaij, Hoes, and Schilder. Drafting of the
manuscript: Buskens, van Staaij, and van den Akker. Critical revision of the manuscript for important intellectual content: Buskens, van Staaij, Hoes, and Schilder. Statistical
analysis: Buskens and van Staaij. Obtained funding:
Buskens, Hoes, and Schilder. Administrative, technical, and
material support: van Staaij and van den Akker. Study supervision: Buskens, Hoes, and Schilder.
Financial Disclosure: None reported.
Funding/Support: This study was supported by grant OG99-060 from the Dutch Health Care Insurance Board.
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