NC: Behavior Change Strategies (2007-2008)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
To compare the effects of an Internet weight loss program alone vs with the addition of behavioral counseling via e-mail provided for 1 year to individuals at risk of type 2 diabetes.
Inclusion Criteria:
  • Access to a computer
  • BMI 27-40
  • 1 or more other risk factors for type 2 diabetes (age 45 or older; family history of diabetes; high cholesterol levels or blood pressure; impaired glucose tolerance; history of gestational diabetes; being delivered of a neonate weighing 4 kg or more; or belonging to a minority group)
Exclusion Criteria:
Major health or psychiatric diseases, pregnancy, or recent weight loss of 4.5 kg or more.
Description of Study Protocol:

Recruitment:  Participants were recruited through newspaper advertisements and were drawn from a waiting list at Brown University School of Medicine/Miriam Hospital, Weight Control and Diabetes Research Center.

Design:  Single-center randomized controlled trial

Blinding used (if applicable):  Not applicable.

Intervention (if applicable):  Subjects were randomized to 1 of 2 treatment programs:  basic Internet weight loss program or the Internet weight loss program plus behavioral e-counseling.  Both groups received 1 face-to-face counseling session and the same core Internet programs and were instructed to submit weekly weights.  Participants in e-counseling submitted calorie and exercise information and received weekly e-mail behavioral counseling and feedback from a counselor.

Statistical Analysis:  All analyses followed an intent-to-treat principle using all randomized participants and assuming no change from baseline for those with missing data.

Changes in weight, waist circumference, dietary intake, and energy expenditure were examined separately using repeated measures analysis of variance when assumptions of the ANOVA were met and nonparametric tests when key assumptions were violated.

Data Collection Summary:

Timing of Measurements:  Baseline, months 3, 6, and 12

Dependent Variables

  • weight
  • waist circumference, fasting blood glucose

Independent Variables:  Internet behavioral counseling

Control Variables:  Internet weight loss program

 

Description of Actual Data Sample:

Initial N: 92 (10 males, 82 females) 

Attrition (final N):  77 attended the 12-month assessment

Age: mean (SD) age of 48.5 (9.4) years

Ethnicity: 89% white

Other relevant demographics

Baseline Characteristics

Basic Internet Group (n=46)

Behavioral e-counseling (n=46)

Education, No (%)

 

 

      High School

7 (15)

7 (15)

      Some College

17 (37)

15 (33)

      College Degree

14 (31)

12 (26)

      Graduate Degree

8 (17)

12 (26)

Marital status, No (%)

 

 

      Married

38 (82.6)

33 (72)

      Divorced

4 (8.7)

8 (17)

      Widowed or never married

4 (8.7)

5 (11)

Age, y

47.3 (9.5)

49.8 (9.3)

Weight, kg

89.4 (12.6)

86.2 (14.3)

BMI

33.7 (3.7)

32.5 (3.8)

Waist circumference, cm

111 (11.7)

108 (12.4)

Fasting blood glucose, mg/dL

95.5 (8.2)

98.9 (9.9)

 

 

 

Anthropometrics:  mean (SD) BMI 33.1 (3.8)

Location: Providence, RI

 

Summary of Results:

 

Variables

Behavioral e-counseling group

Measures and confidence intervals

Basic Internet group

Measures and confidence intervals

Statistical Significance of Group Difference

Weight loss

(Intent-to-treat analysis at 12 months)

-4.4 (6.2) kg

95% CI for difference,  -0.1 to 4.9

-2.0 (5.7) kg

95% CI for difference, -0.1 to 4.9

x2=4.4

p=.04

Reduction in percentage of initial body weight

(Intent-to-treat analysis at 12 months)

4.8%    

2.2%

 

x2=4.8

p=.03

BMI    

(Intent-to-treat analysis at 12 months)

-1.6 (2.2)

95% CI for difference,  -0.04 to 1.8

-0.8 (2.1)

95% CI for difference, -0.04 to 1.8

x2=4.7

p=.03

Waist circumference

(Intent-to-treat analysis at 12 months)

-7.2 (7.5) cm

95% CI for difference,  0.02 to 5.6

-4.4 (5.7) cm

95% CI for difference,  0.02 to 5.6

F=4.0

p=.05

Weight loss at 3 months (based on the 77 participants who completed the 12-month follow-up)

-4.1 (3.7) kg -2.7 (3.3) kg p=.04

Weight loss at 6 months (based on the 77 participants who completed the 12-month follow-up)

-5.2 (5.4) kg -2.5 (4.7) kg p=.007

Weight loss at 12 months (based on the 77 participants who completed the 12-month follow-up)

-5.3 (6.5) kg -2.3 (6.1) kg p=.03
Reduction in fasting plasma glucose at 3 months -4.6 (7.9) mg/dL -0.3 (8.4) mg/dL t=2.5; p=.01
Reduction in percentage of calories consumed from fat from 0 to 12 months     4% 1% F=3.6; p=.06

Logins to the Web site were significantly greater in the behavioral e-counseling group at all time points (p<.05).

Other Findings

 

Author Conclusion:

This study showed that an Internet weight loss program with behavioral e-counseling produce significantly more weight loss and greater reductions in waist circumference at 1 year than the same basic program without behavioral e-counseling in individuals at risk of type 2 diabetes.  The addition of e-counseling doubled the percentage of initial body weight lost.

Outcomes achieved in this study with only 1 in-person meeting were comparable to previous results suggesting that Internet behavioral programs may offer an alternative to more burdensome clinic programs.

Results from this study suggest that therapist contact improve 1-year efficacy. 

This study demonstrates that Internet interventions can be used for longer periods; a necessary model for treatment of chronic diseases.

Funding Source:
Not-for-profit
0
Foundation associated with industry:
Reviewer Comments:
Limitations of study:  small sample size, no follow-up beyond 1 year, predominantly women, white, college education, people with computer access.
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) 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
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) Yes
 
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
2. Was the selection of study subjects/patients free from bias? Yes
  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? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? Yes
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) Yes
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? Yes
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) Yes
  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
  3.6. 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
  4.1. Were follow-up methods described and the same for all groups? No
  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
  4.4. Were reasons for withdrawals similar across groups? Yes
  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? N/A
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? N/A
  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.) 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
  5.5. 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
  6.1. 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? N/A
  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
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? No
  6.6. Were extra or unplanned treatments described? No
  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
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
  7.2. 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
  7.4. 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
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  7.7. Were the measurements conducted consistently across groups? 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
  8.2. 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
  8.4. 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)? Yes
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? Yes
  8.6. Was clinical significance as well as statistical significance reported? No
  8.7. If negative findings, was a power calculation reported to address type 2 error? N/A
9. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? Yes
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.2. Was the study free from apparent conflict of interest? Yes