Toward the development of self-help health behaviour change programs: weight loss by correspondence.
The goal of this study was to evaluate a correspondence weight control program, and to assess the impact of three program elements (weekly homework, interim weigh-ins, and participation deposits) individually and in combination. All treated participants received 15 weekly standard lessons by mail. Three program features were varied factorially: a) homework assignments, b) interim weigh-ins and c) a deposit refunded contingent on returning homework and/or attending interim weigh-ins. Participants were assigned randomly to active treatment conditions or a delayed treatment control group. Among treated males (N = 14), initial average weight loss and BMI reduction were 9.6 kg and 3.1 respectively; average net weight loss and BMI reduction at one year follow-up were 5.8 kg and 1.9 respectively. Among treated females (N = 128), initial average weight loss and BMI reduction were 3.1 kg and 1.2 respectively; average net weight loss and BMI reduction at one year were 2.3 kg and .88 respectively. Women in all treated groups, except lessons only, showed a greater BMI reduction than untreated controls at the end of treatment. Women in conditions including both homework and interim weigh-ins had greater initial BMI reductions (M = 1.6) than those who received lessons only (M = .76). At one year, net BMI reductions were comparable across all treated groups. Of the 42 women initially registered in conditions that included both homework and weigh-ins, 12 who denied joining other programs lost at least 4.5 kg (M = 7.1) during treatment, and 7 had a net loss of at least 4.5 kg (M = 8.0) at one year without apparent involvement in any other program.
Department of Health Studies, University of Waterloo, Ontario.
R
R
Cameron
M A
MA
MacDonald
R P
RP
Schlegel
C I
CI
Young
S E
SE
Fisher
J D
JD
Killen
T
T
Rogers
L
L
Horlick
L F
LF
Shepel
D000328:Adult; D015709:Correspondence as Topic; D005260:Female; D006266:Health Education / Q000379:methods*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000517:prevention & control*; D009864:Ontario; D010043:Outcome and Process Assessment, Health Care; D012657:Self-Help Groups; D015431:Weight Loss