EAL

NC: Maintenance of Health/Behavior Change Following Short-term CBT (2008)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

This report is a 3.3-year follow-up of patients who lost weight in a medically-supervised, weight loss program that combined VLCD and group behavior therapy.

Inclusion Criteria:

All patients who had entered the program in 1984 and had remained in the program at least eight weeks.

Exclusion Criteria:

Re-entered the program
Were on a VLCD at the time of the interview
Failed to answer all questions on the interview.

Description of Study Protocol:

Recruitment

All patients who had entered the VLCD program in 1984 and remained in the program at least eight weeks.

Design

The follow-up interview was conducted an average of 3.3 years after completion of the VLCD and consisted of a questionnaire administered over the telephone by trained clinic personnel
Twenty patients who had completed this interview were randomly selected to answer the question of whether they had attended other weight loss programs during the 3.3 years since the period following the VLCD.

Blinding Used

Not applicable.

Intervention

Not applicable.

Statistical Analysis

Patients’ answers to the questionnaire were combined with their clinic data and analyzed using the statistical package, SPSSx
Sub-groups were compared using Student's T-test or analysis of variance with a post hoc Scheffe test, whichever was appropriate
Associations were tested using Pearson's product moment correlations and multiple regression analysis
Proportional differences were analyzed by X²
All tests were two-tailed and P<0.05 was considered significant.

Data Collection Summary:

Timing of Measurements

The phone interview was conducted 3.3 years following intervention.

Dependent Variables

Body Mass Index (BMI) was calculated as weight divided by height² (kg per m²)
Minimum weight was the lowest weight achieved by the patient during any phase of the program, usually toward the end of the VLCD
Percentage regain was the weight change from minimum to follow-up divided by the maximum amount of weight lost while in the program
'Losers’ refers to those patients whose current weight was less than their baseline weight
'Gainers’ refers to those patients who had regained 100% or more of their lost weight.

Independent Variables

Not applicable.

Control Variables

Not applicable.

Description of Actual Data Sample:

Initial N: 199 attended at least eight weeks of the program
Attrition (final N): 126 were located; 8 excluded. Final N: 118 (38 males, 80 females)
Age: 46.9 years (SD 11.2 years)
Other relevant demographics:

Baseline data

Variable	All (N=118) Mean, SD	Males (N=38) Mean, SD	Females (N=80) Mean, SD
Age	46.9, 11.2	46.3, 11.3	47.3, 11.3
Baseline Weight (kg)	118.3, 31.1	140.1, 34.2	108.0, 23.4
Baseline BMI (kg/m²)	41.1, 9.2	43.4, 10.5	39.9, 8.4

Location: Division of Preventive and Nutritional Medicine, William Beaumont Hospital, Birmingham, MI.

Summary of Results:

Follow-up Data

Variable	All (N=118) Mean, SD	Males (N=38) Mean, SD	Females (N=80) Mean, SD
Minimum Weight (kg)	87.0, 25.5	95.9, 28.6	82.7, 22.8
Minimum BMI (kg.m²)	30.3, 8.2	29.8, 8.9	30.6, 7.9
Follow-up Weight (kg)	104.7, 26.3	120.1, 31.2	97.5, 20.1
Follow-up BMI (kg/m²)	36.6, 8.8	37,4, 10.2	36.2, 8.0
Maximum Weight Change in Program (kg)	-31.2, 23.0	-44.2, 32.2	-25.2, 13.5
Maximum BMI Change in Program (kg/m²⁾	-10.7, 7.2	-13.6, 9.6	-9.3, 5.1
Regain (kg)	17.8, 19.3	24.1, 22.2	14.7, 17.1
Percentage Regained	60.9, 28.2	63.0, 49.2	60.0, 76.3
Weight Change Baseline to Follow-up (kg)	-13.6, 20.9	-20.1, 27.8	-10.5, 16.0
BMI Change Baseline to Follow-up (kg/m²)	-4.4, 6.6	-6.1, 8.2	-3.6, 5.6
Percentage Weight Change Baseline to Follow-up	-10.0, 13.4	-12.8, 15.7	-8.7, 12.1
Weeks on VLCD	24.0, 14.0	26.5, 16.4	22.8, 12.7
Total Weeks in the Program	51.6, 48.1	59.6, 52.5	47.9, 45.7
Exercise Duration (hours/week)	2.7, 4.8	2.2, 3.2	2.9, 5.5

Comparison of Weight Changes in Exercises and Non-exercisers

Variable	Exercisers	Non-exercisers
Weight Change Baseline to Follow-up (kg)	-17.2	-8.4*
BMI Change Baseline to Follow-up (kg/m²)	-5.6	-2.8*
Percentage Weight change Baseline to follow-up	-12.5	-6.7*
Percentage Re-gained	50.1	75.7*

*Difference between exercisers and non-exercisers significant at P<0.04.

Other Findings

Participation in interim programs

Of the 20 randomly selected patients who participated in this additional survey, one patient refused to be interviewed
Four patients reported that they had participated in another obesity program during the follow-up period of 3.3 years. These four indicated that they did not experience weight loss in this interim program.

Author Conclusion:

The results indicate that many very obese patients who participate in a combination VLCD and behavioral modification program may experience considerable success at weight loss and maintenance of weight loss
These data also suggest that exercise contributes to weight loss and its maintenance.

Funding Source:

Other:

not noted

Reviewer Comments:

Fifty-nine percent of patients who were originally in the VLCD program in 1984 were phone interviewed 3.3 years after they completed the program

Physical measurements were not completed
75% of these subjects reported a 37.5% regain of the weight they lost.

Quality Criteria Checklist: Primary Research
Relevance Questions
	1.	Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)	N/A
	1.	Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)	N/A
	2.	Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?	Yes
	2.	Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?	Yes
	3.	Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?	Yes
	3.	Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?	Yes
	4.	Is the intervention or procedure feasible? (NA for some epidemiological studies)	Yes
	4.	Is the intervention or procedure feasible? (NA for some epidemiological studies)	Yes

Validity Questions
	1.	Was the research question clearly stated?	Yes
1.	Was the research question clearly stated?		Yes
	1.1.	Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?	Yes
	1.1.	Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?	Yes
	1.2.	Was (were) the outcome(s) [dependent variable(s)] clearly indicated?	Yes
	1.2.	Was (were) the outcome(s) [dependent variable(s)] clearly indicated?	Yes
	1.3.	Were the target population and setting specified?	Yes
	1.3.	Were the target population and setting specified?	Yes
	2.	Was the selection of study subjects/patients free from bias?	No
2.	Was the selection of study subjects/patients free from bias?		No
	2.1.	Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?	No
	2.1.	Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?	No
	2.2.	Were criteria applied equally to all study groups?	N/A
	2.2.	Were criteria applied equally to all study groups?	N/A
	2.3.	Were health, demographics, and other characteristics of subjects described?	No
	2.3.	Were health, demographics, and other characteristics of subjects described?	No
	2.4.	Were the subjects/patients a representative sample of the relevant population?	No
	2.4.	Were the subjects/patients a representative sample of the relevant population?	No
	3.	Were study groups comparable?	N/A
3.	Were study groups comparable?		N/A
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	N/A
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	N/A
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	N/A
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	N/A
	3.3.	Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)	N/A
	3.3.	Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)	N/A
	3.4.	If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis?	N/A
	3.4.	If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis?	N/A
	3.5.	If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.)	N/A
	3.5.	If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.)	N/A
	3.6.	If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?	N/A
	3.6.	If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?	N/A
	4.	Was method of handling withdrawals described?	Yes
4.	Was method of handling withdrawals described?		Yes
	4.1.	Were follow-up methods described and the same for all groups?	N/A
	4.1.	Were follow-up methods described and the same for all groups?	N/A
	4.2.	Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)	Yes
	4.2.	Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)	Yes
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	Yes
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	Yes
	4.4.	Were reasons for withdrawals similar across groups?	N/A
	4.4.	Were reasons for withdrawals similar across groups?	N/A
	4.5.	If diagnostic test, was decision to perform reference test not dependent on results of test under study?	N/A
	4.5.	If diagnostic test, was decision to perform reference test not dependent on results of test under study?	N/A
	5.	Was blinding used to prevent introduction of bias?	No
5.	Was blinding used to prevent introduction of bias?		No
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	No
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	No
	5.2.	Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)	No
	5.2.	Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)	No
	5.3.	In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?	N/A
	5.3.	In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?	N/A
	5.4.	In case control study, was case definition explicit and case ascertainment not influenced by exposure status?	N/A
	5.4.	In case control study, was case definition explicit and case ascertainment not influenced by exposure status?	N/A
	5.5.	In diagnostic study, were test results blinded to patient history and other test results?	N/A
	5.5.	In diagnostic study, were test results blinded to patient history and other test results?	N/A
	6.	Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?	Yes
6.	Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?		Yes
	6.1.	In RCT or other intervention trial, were protocols described for all regimens studied?	Yes
	6.1.	In RCT or other intervention trial, were protocols described for all regimens studied?	Yes
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	Yes
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	Yes
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	Yes
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	Yes
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	Yes
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	Yes
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	N/A
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	N/A
	6.6.	Were extra or unplanned treatments described?	Yes
	6.6.	Were extra or unplanned treatments described?	Yes
	6.7.	Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?	N/A
	6.7.	Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?	N/A
	6.8.	In diagnostic study, were details of test administration and replication sufficient?	N/A
	6.8.	In diagnostic study, were details of test administration and replication sufficient?	N/A
	7.	Were outcomes clearly defined and the measurements valid and reliable?	Yes
7.	Were outcomes clearly defined and the measurements valid and reliable?		Yes
	7.1.	Were primary and secondary endpoints described and relevant to the question?	Yes
	7.1.	Were primary and secondary endpoints described and relevant to the question?	Yes
	7.2.	Were nutrition measures appropriate to question and outcomes of concern?	Yes
	7.2.	Were nutrition measures appropriate to question and outcomes of concern?	Yes
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	Yes
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	Yes
	7.4.	Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?	Yes
	7.4.	Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?	Yes
	7.5.	Was the measurement of effect at an appropriate level of precision?	Yes
	7.5.	Was the measurement of effect at an appropriate level of precision?	Yes
	7.6.	Were other factors accounted for (measured) that could affect outcomes?	???
	7.6.	Were other factors accounted for (measured) that could affect outcomes?	???
	7.7.	Were the measurements conducted consistently across groups?	N/A
	7.7.	Were the measurements conducted consistently across groups?	N/A
	8.	Was the statistical analysis appropriate for the study design and type of outcome indicators?	Yes
8.	Was the statistical analysis appropriate for the study design and type of outcome indicators?		Yes
	8.1.	Were statistical analyses adequately described and the results reported appropriately?	Yes
	8.1.	Were statistical analyses adequately described and the results reported appropriately?	Yes
	8.2.	Were correct statistical tests used and assumptions of test not violated?	Yes
	8.2.	Were correct statistical tests used and assumptions of test not violated?	Yes
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	Yes
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	Yes
	8.4.	Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)?	No
	8.4.	Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)?	No
	8.5.	Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?	No
	8.5.	Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?	No
	8.6.	Was clinical significance as well as statistical significance reported?	Yes
	8.6.	Was clinical significance as well as statistical significance reported?	Yes
	8.7.	If negative findings, was a power calculation reported to address type 2 error?	???
	8.7.	If negative findings, was a power calculation reported to address type 2 error?	???
	9.	Are conclusions supported by results with biases and limitations taken into consideration?	Yes
9.	Are conclusions supported by results with biases and limitations taken into consideration?		Yes
	9.1.	Is there a discussion of findings?	Yes
	9.1.	Is there a discussion of findings?	Yes
	9.2.	Are biases and study limitations identified and discussed?	Yes
	9.2.	Are biases and study limitations identified and discussed?	Yes
	10.	Is bias due to study's funding or sponsorship unlikely?	Yes
10.	Is bias due to study's funding or sponsorship unlikely?		Yes
	10.1.	Were sources of funding and investigators' affiliations described?	Yes
	10.1.	Were sources of funding and investigators' affiliations described?	Yes
	10.2.	Was the study free from apparent conflict of interest?	Yes
	10.2.	Was the study free from apparent conflict of interest?	Yes