Adherence is a multi-dimensional construct in the POUNDS LOST trial.
Research on the conceptualization of adherence to treatment has not addressed a key question: Is adherence best defined as being a uni-dimensional or multi-dimensional behavioral construct? The primary aim of this study was to test which of these conceptual models best described adherence to a weight management program. This ancillary study was conducted as a part of the POUNDS LOST trial that tested the efficacy of four dietary macronutrient compositions for promoting weight loss. A sample of 811 overweight/obese adults was recruited across two clinical sites, and each participant was randomly assigned to one of four macronutrient prescriptions: (1) Low fat (20% of energy), average protein (15% of energy); (2) High fat (40%), average protein (15%); (3) Low fat (20%), high protein (25%); (4) High fat (40%), high protein (25%). Throughout the first 6 months of the study, a computer tracking system collected data on eight indicators of adherence. Computer tracking data from the initial 6 months of the intervention were analyzed using exploratory and confirmatory analyses. Two factors (accounting for 66% of the variance) were identified and confirmed: (1) behavioral adherence and (2) dietary adherence. Behavioral adherence did not differ across the four interventions, but prescription of a high fat diet (vs. a low fat diet) was found to be associated with higher levels of dietary adherence. The findings of this study indicated that adherence to a weight management program was best conceptualized as being multi-dimensional, with two dimensions: behavioral and dietary adherence.
Pennington Biomedical Research Center, LSU System, 6400 Perkins Rd., Baton Rouge, LA, USA. williada@pbrc.edu
Donald A
DA
Williamson
Stephen D
SD
Anton
Hongmei
H
Han
Catherine M
CM
Champagne
Ray
R
Allen
Eric
E
LeBlanc
Donna H
DH
Ryan
Katherine
K
McManus
Nancy
N
Laranjo
Vincent J
VJ
Carey
Catherine M
CM
Loria
George A
GA
Bray
Frank M
FM
Sacks
D001519:Behavior; D015331:Cohort Studies; D003201:Computers; D004032:Diet; D004038:Diet, Reducing / Q000379:methods; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D009765:Obesity / Q000178:diet therapy* / Q000523:psychology*; D050177:Overweight / Q000178:diet therapy* / Q000523:psychology*; D010349:Patient Compliance / Q000523:psychology*; D013997:Time Factors