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801249 893.898
International Journal of Obesity (2000) 24, 893±898
ß 2000 Macmillan Publishers Ltd All rights reserved 0307±0565/00 $15.00www.nature.com/ijo
Effective long-term treatment of obesity:
JD Latner1*, AJ Stunkard2, GT Wilson1, ML Jackson3, DS Zelitch3{ and E Labouvie1
1Department of Psychology, Rutgers University, Piscataway, NJ, USA; 2Department of Psychiatry, University of Pennsylvania,
Philadelphia, PA, USA; and 3Trevose Behavior Modi®cation Program, Trevose, PA, USA
BACKGROUND: Despite the well-documented success of behavioral techniques in producing temporary weight loss,
treatment is typically followed by weight regain. The maintenance of treatment effects may therefore be the greatest
challenge in the long-term management of obesity, and continuous care may be necessary to achieve it.
OBJECTIVE: To describe the design and evaluate the effectiveness of the Trevose Behavior Modi®cation Program, a
potentially widely replicable self-help weight loss program offering continuous care.
DESIGN: A description of the course of all subjects (n 171) who entered the Trevose program during 1992 and 1993.
SUBJECTS: One hundred and forty-six women aged 44.1Æ 11.7 y with a body mass index (BMI, kgam2) of 33.2Æ 4.4,
and 25 men aged 49.0Æ 19.6 with a BMI of 35.1Æ 5.2 enrolled in the Trevose program during 1992 ± 1993.
RESULTS: Mean duration of treatment was 27.1 months, with 47.4% of members still in treatment at 2 y and 21.6% at
5 y. Mean intent-to-treat weight loss was 13.7Æ 0.5% of initial weight, or 12.8Æ 0.5 kg. As long as they remained in
treatment, almost all participants lost at least 5% of their initial weight and at least 83% lost more than 10%. Members
completing 2 y of treatment lost an average of 19.3% of their initial body weight (17.9 kg); at 5 y the loss was still 17.3%
(15.7 kg). After leaving the program, subjects regained weight but remained 4.7% (4.5 kg) below their pretreatment
CONCLUSION: A low-cost program offering treatment of inde®nite duration produced large long-term weight losses
and may be suitable for widespread replication.
InternationalJournal of Obesity (2000) 24, 893±898
Keywords: weight loss; weight maintenance; continuing care; self help
general population may be limited.4 Behavioral pro-
grams for the control of obesity have potential for
more widespread use, but evidence of their long-term
The overarching problem in the treatment of obesity is
effectiveness is also limited. In six studies with
the consistency with which weight lost in treatment is
follow-up periods of at least 4 y, the mean weight at
regained. This problem has led to the view that
follow-up was only 1.9 kg lower than at the beginning
obesity is a chronic disorder which requires long-
term treatment.1 The two forms of treatment are
Two reports indicate that long-term weight losses
pharmacologic and behavioral. In 1997, the appear-
can be achieved. The ®rst report described a register
ance of valvular heart disease in a signi®cant number
of more than 1000 persons from all parts of the US
of persons who took dexfen¯uramine in combination
who maintained large weight losses for a period of
with phentermine, after years of apparently safe use of
years.11 These subjects reported that their success was
DL-fen¯uramine, raised concern over the long-term
due to continuing implementation of strategies that are
use of any medication.2,3 The advent of two appar-
core elements of behavioral treatment programs: self-
ently safer medications, sibutramine and orlistat, pro-
monitoring of food intake and physical activity,
mises only modest weight losses, and their long term
weekly weighing, better nutrition, and exercise. The
safety and effectiveness still need to be established.
second report described the only program that con-
Since medication for obesity must be administered by
tinued treatment for as long as 4 y.12 In this Swedish
physicians on an individual basis, its effect on the
study of 104 severely obese (body mass index,
BMI 41.5 y) persons (81 women and 26 men),
69% remained in treatment for 4 y and lost an average
*Correspondence: JD Latner, Department of Psychology,
Rutgers University, 152 Frelinghuysen Road, Piscataway,
of 11.7 kg. During this time, behavioral measures
were employed initially on a weekly basis and subse-
quently less frequently. Any increase in weight led to
{This work is dedicated to the memory of David Zelitch (1924 ±
1998), whose leadership and abilities through decades of
reinstitution of more intensive outpatient therapy and,
devotion have made the Trevose Behavior Modi®cation Program
if that failed, to inpatient therapy. Ten to twelve year
follow-up data indicated a maintenance of weight
Received 21 June 1999; revised 9 November 1999; accepted
These rare successes suggesting the importance of
members. Thereafter the cumulative weight loss goals
treatment duration are supported by a meta-analysis
are 22% of the total goal for the second month, 30%
that found that treatment duration was signi®cantly
for the third month, and so forth until 90% of the goal
correlated with weight loss after treatment and at
is achieved. After the ®rst 5 weeks, absences may
follow-up.14 Another study showed that 40 weeks of
be excused, but only with 2 weeks advance notice.
treatment produced signi®cantly greater weight losses
During vacations, members must mail a record of
than did 20 weeks, both at 40 weeks (13.6 vs 6.4 kg)
their weight to their group leader on the day of their
and at 72 weeks (9.9 vs 4.6 kg) after the start of
usual meeting. Failure to meet attendance or weight
loss requirements during the ®rst 4 months results
These studies suggest two causes of the poor long-
in immediate dismissal from the program. After 4
term results of treatment of obesity. The ®rst is
months, members who fail to meet a weight loss
inadequate implementation (rather than inadequate
requirement are given a grace period of one month
techniques). The second is inadequate duration of
(`drop-out') or 2 months (`parole') in which to lose
treatment. We report here an effective behavioral
the required weight, but once again, failure results in
treatment program of long duration, with costs so
low that it can be widely replicated and can serve as
When members have reached, and maintained, their
weight loss goal for 4 months, the requirement for
attendance drops to two meetings a month and, after 8
months, to one meeting a month. After 12 months of
successful maintenance, members are graduated to
`independence level' and are not required to attend
meetings. About 10% choose to continue regular
The Trevose Behavior Modi®cation Program was
attendance and they form the pool from which new
begun in 1970 by David Zelitch, a formerly obese
group leaders are chosen. Those who do not continue
man, as a means of helping himself maintain his
to attend must keep weight records and mail them in
weight loss. The program now treats approximately
to their group leader monthly. A weight gain of up to
1000 persons in its central location and in 63 smaller
10 pounds (above their weight when they reached
satellite groups in Philadelphia and its surrounding
`independence level') triggers an urgent request for
areas. It is lay-directed and lay-administered, staffed
the member to return for weekly meetings until the
entirely by volunteers and it charges no fees. The
extra weight is lost. If, however, the gain is greater
Trevose Program has been operating in its present
than 10 pounds, the members are not allowed to rejoin
form for more than 25 y and has earned recognition by
the program until their weight is no more than 10
other weight loss programs in the Philadelphia area
pounds above their `independence level' weight.
for its willingness to accept all patients refused treat-
This report describes the outcome of all subjects
ment by them, usually for lack of funds.
enrolled in the Trevose program during the years
Like most behavioral programs, the Trevose pro-
1992 ± 1993. Information on these individuals
gram involves standard techniques, delivered in
included gender, age on entry into the program, initial
weekly 1 h meetings of groups of about 10 persons.
weight, BMI, weight loss goal and weights recorded
It includes weigh-ins, self-monitoring of food intake
monthly during treatment. Participant ¯ow during the
and physical activity, measures to slow the rate of
eating, and social support. Subjects are weighed at
each of the weekly meetings on a balance-beam scale.
The ®rst step in the program is selection of the
applicant's weight loss goal. Goals are derived from
the 1959 tables of the Metropolitan Life Insurance
Company16 and are subject to two constraints: they
must be within the range of normal weight and no less
than 20 nor more than 100 pounds less than the
applicant's initial body weight. This latter constraint
excludes very obese persons with their poorer prog-
nosis as well as persons with solely cosmetic con-
cerns. Once the overall goal is set, monthly weight
loss goals are established, based on a cumulative
Unlike most behavior therapy programs, attendance
and achieving weight loss goals are strictly enforced.
A critical part of the program is a 5-week trial of
treatment. During this time attendance is mandatory,
as is the loss of 15% of the total weight loss goal; only
those meeting these requirements are accepted as full
Figure 1 Participant ¯ow during the study.
A total of 134 of 171 persons who were full
women and 33 men) entered the 5-week trial which
members of the 1992 ± 1993 cohort dropped out
was completed by 171 (146 women and 25 men), who
during the 5 y of membership in the program.
became full members. Ages of female and male full
Reported current weight was obtained from 77
members were 44.1Æ 11.7 and 49.0Æ 10.6, respec-
(58%) of these drop-outs through telephone contact,
tively, and their BMIs were 33.2Æ 4.4 and 35.1Æ 5.2.
which took place an average of 47.1 months after they
Mean duration of treatment was 27.1 months.
had left the program. This study was approved by the
Figure 2 shows the percentage of full members con-
Rutgers University Institutional Review Board.
tinuing in the program: 61.4% at 1 y, 47.4% at 2 y and
Mean intent-to-treat weight loss for all full mem-
bers was 13.7Æ 0.5% of initial weight or
The most important aspect of this study is the long
12.8Æ 0.5 kg. (Percentage weight loss and kg of
duration of treatment (Figure 2). There is no standard
weight loss are quite similar for all measurements.)
way of displaying the weight loss data of persons who
The percentage of members who lost 5% and 10% of
remain in a program for long, and varying, periods of
their initial body weight is depicted in Table 1. As
time. Accordingly, we devised a method, depicted in
long as they were in the program, almost all partici-
Figure 3, that shows the weight loss of participants
pants lost at least 5% of their initial weight and at least
who remained in the program for designated periods
of time. The weight loss curves include subjects who
Figure 3 illustrates this critical aspect of the Tre-
reached the designated cut-off points (6, 12, 24, 30
vose program Ð the maintenance of weight losses of
and 60 months). Weights of participants who
persons as long as they remain in the program. It
remained in the program beyond a cut-off point but
depicts the weight losses of members who remained in
did not reach the next cut-off point are shown until the
the program for varying periods of time: 6, 12, 24, 36
earlier cut-off point (ie weights of members remaining
and 60 months. The 61.4% of the full members who
in the program between 36 and 59 months are
remained in treatment at 1 y lost 18.5% of their
depicted through the 36th month of participation).
original weight (17.1 kg), and the 47.4% who
Regression analyses were used to estimate predic-
remained at 2 y lost 19.3% of their original weight
(17.9 kg). At 5 y, weight loss of members remaining
in treatment averaged 17.3% of original weight
(15.7 kg). The percentages are of all full members,
Figure 1 shows the course of the 329 persons who
applied to Trevose in 1992 ± 1993. Of these, 202 (169
Figure 3 Weight losses of full members who remained in the
program for varying periods of time. The curves show the
weight losses of members who completed varying durations of
treatment: 6, 12, 24, 36 and 60 months. The percentages refer to
the percent of all full members who reached these cut-off points.
For example, at 60 months, 22% were still in treatment and had
lost 17% of their initial weight. This method of presentation is
conservative, since it does not depict weight losses between cut-
off points, for persons who remained in the program beyond one
Figure 2 Decrease in the percent of members attending the
cut-off point but did not reach the next cut-off point. The ®gure
Trevose Behavior Modi®cation Program during the 5 y study
does not include the 20% of full members who dropped out of
period. 100% consists of full members who had completed the
treatment during the ®rst 6 months. Numbers in the ®gure have
5 week trial period. See text for explanation.
Table 1 Mean weight loss of Trevose and Orlistat subjects at 6, 12, 24, 36, 48 and 60 months and those achieving weight losses of 5%
or more and 10% or more of initial body weight
excluding the 19.6% who dropped out at various times
In the present study, the largest percent of weight
during the ®rst 6 months and whose average weight
loss, 20%, did not occur until 30 months of treatment,
emphasizing again the advantages of long-term treat-
Follow-up weights for the Trevose program were
ment. By contrast, maximum weight loss in traditional
obtained on 58% of members who had dropped out.
behavioral programs consistently occurs at 6
These members did not differ from those who were
not contacted in terms of age, baseline weight or
The high drop-out rate by the end of the ®fth year of
weight losses at 1, 6, and 12 months of treatment.
treatment calls for caution in interpreting the results.
Their average net weight loss (weight below baseline
Nevertheless, the drop-out rate at earlier points in
values) 47.1 months after leaving the program was
treatment is comparable to other treatment studies. It
4.7Æ 1.1% or 4.5Æ 2.3 kg. The length of follow-up
may be helpful to compare the Trevose results with
was not related to the size of the net weight loss.
those of a recent, large, 2 y controlled trial of the
Three major predictors of weight loss, as deter-
lipase inhibitor Orlistat.18 This study enrolled 1187
mined by regression analysis, accounted for 60% of
persons who were somewhat heavier (BMI 36.5)
the variance in weight loss in kg (F(3,162) 48.3;
than the Trevose subjects (BMI of men 35.1, of
P ` 0.001), and 47% of the variance in percentage
women 33.2) and greater weight favors greater
weight loss (F(3,162) 81.7; P ` 0.001). The predic-
weight loss. After a 4 week placebo run-in period,
tors were months in treatment (b 0.51; P ` 0.001),
comparable to the Trevose 5-week trial period, all
weight loss during the ®rst month (b 0.30; P ` .001)
subjects received a diet, behavioral consultations and
and initial BMI (b 0.27; P ` 0.001). The higher the
either Orlistat or placebo. Subjects remaining in
initial BMI, the greater the weight loss.
treatment were comparable in the two studies: at 1 y
Trevose 62%, Orlistat 69%, placebo 57%; at 2 y,
Trevose 47%, Orlistat (drug and placebo) 43%.
During the 2 y of treatment, Trevose subjects lost
far more weight. Table 1 shows that at 1 y the mean
weight loss for Trevose (19%) was twice that for
Orlistat (9%) or placebo (6%). At 2 y the weight loss
The Trevose Behavior Modi®cation Program is a
for Trevose (19%) approached three times that for
surprisingly effective weight control program, parti-
Orlistat (8%) and placebo (6%). At 1 y, the percentage
cularly when considered in the light of its minimal
of subjects who lost at least 10% of their initial weight
at Trevose was 97% compared to 39% for Orlistat and
The results of the Trevose program are dif®cult to
25% for placebo. At 2 y 94% of Trevose subjects had
compare with those of other programs because of its
lost 10% of their initial weight compared to 34% for
far greater duration of treatment. Thus, of the six
Orlistat and 18% for placebo. The Orlistat study
programs with follow-up periods of at least 4 y,
terminated at two years, while weight losses of
treatment averaged only 16.4 weeks in duration.5±10
Trevose subjects in treatment remained substantial
Four-year follow-up of these programs showed an
average net weight loss of 1.9 kg compared to 4.5 kg
The self-help format of the Trevose program does
for Trevose drop-outs contacted at follow-up. Weights
not appear to be responsible for its success, which was
for the Trevose subjects may be somewhat more
far greater than that of two other self help programs
reliable than those of the other six studies, since
for obesity: Take Off Pounds Sensibly (TOPS)19 and
they were obtained on a substantial proportion of
Overeaters Anonymous.20 A study of 21 TOPS chap-
subjects (58%) who were representative of those not
ters in the Philadelphia area revealed that the average
contacted. The representativeness of the subjects of
member lost 6.8 kg but fewer persons remained in
treatment than in Trevose: 53% survived for 1 y and
30% for 2 y.19 Overeaters Anonymous does not
Second, one of the very few criteria for exclusion
from Trevose is critical: no previous members are
The content of the Trevose program does not seem
accepted. Applicants learn at their ®rst encounter that
different from that of most other behavioral weight
this is a once in-a lifetime opportunity. As the Trevose
control programs. What is different is its provision for
Leaders' Manual makes clear, `this is a last chance
treatment on a continuing basis. As noted above,
behavior therapy appears effective as long it is used:
Third, prospective candidates learn about Trevose
at 2 y weight loss was 19% of initial weight and at 5 y
primarily from satis®ed members who describe the
expectations. They arrive highly motivated and know
The behavior modi®cation component of the pro-
gram contains no unique features. It relies on old-
Fourth, the rules are in force from the beginning,
fashioned behavior therapy; little has changed since it
with the critical requirement that members complete
was ®rst introduced in 1971 in the early days of the
the 5-week trial of treatment and lose 15% of goal
®eld. At the time that one of the authors (AJS) and
weight. This trial period is of great importance, for it
Henry Jordan were helping David Zelitch implement
introduces members to the practical aspects of the
it at Trevose, it was tested in another setting: the 21
program and, particularly, its non-negotiable require-
TOPS chapters in the Philadelphia area noted earlier.
As part of a larger controlled trial, the leaders of four
Fifth, members know from the beginning that fail-
TOPS chapters were taught the principles of behavior
ure to meet attendance and weight loss goals is
modi®cation and trained with the help of a behavioral
grounds for dismissal. The message is, `We take this
weight loss manual. Their results over a period of 12
work very seriously and expect that you will'.
weeks were compared with those of four matched
These circumstances appear to be responsible for
TOPS chapters that continued their standard pro-
the successful implementation of the Trevose pro-
gram. The behavioral program decreased drop-out
gram Ð its simple and unambiguous contingencies:
rate, both during treatment and at a 9-month follow-
if members do not attend or if they fail to meet their
up, to 41% compared to 67% for the standard
weight loss goal, they are out and cannot come back.
program. Weight loss at the end of the behavioral
No bargaining, no second chances. This implementa-
program was 0.9 kg vs a gain of 0.3 kg in the standard
tion and the opportunity for continuing care are the
program.21 The difference between the results of the
hallmarks of this successful program.
TOPS and the Trevose behavioral programs could not
The time is ripe for replication and additional
have been more striking, leading us to look beyond
testing of the Trevose model on a large scale. Such
the program's content for an explanation of its
application, by both state and country health depart-
ments, would have many bene®ts. It would bring low-
It is, of course, possible that these results may be
cost weight loss to large populations and would
due to particular characteristics of the group examined
facilitate studies of the mechanisms of the Trevose
here. However, there are few restrictions on who can
program that might further increase its effectiveness.
apply and the applicants do not appear to differ from
the vast majority of persons seeking behavioral treat-
ment for obesity. Even the predictors of weight loss in
The authors are grateful to Theresa Chilton, Louise
Trevose and other programs do not differ. The amount
Fisher, Mildred Gamble, Sue Hirsch, and Arlene
of weight lost during the ®rst month of treatment, the
Robinson, volunteers at the Trevose Behavior Mod-
duration of treatment and the initial BMI, highly
i®cation Program, for their valuable administrative
predictive in the Trevose program, are also predictive
in other programs reported in the literature.22 How-
ever, no other treatment program in the US has shown
this level of long-term effectiveness, even in a speci®c
population. These results provide preliminary support
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Unità dei cristiani e temi etici L'incontro panortodosso a Istanbul di Marco Bellizi L'unità degli ortodossi. Ma anche una posizione comune sui temi della bioetica. El'attenzione confermata all'ambiente, tema da inserire sempre di più nella catechesi,nelle omelie e in generale nelle attività pastorali. Sono questi i punti nodali deldocumento finale dell'incontro panortodosso che si è