Sixteen studies (n=539) were included in the review. Samples sizes ranged from 10 to 70 participants. Participant attrition rates ranged from 0% to 65% (mean 31%). Most studies used convenience samples and appeared to be case series that assessed changes from baseline; some appeared to have separate comparison groups. At least two studies were randomised controlled trials (RCTs). Intervention duration ranged from six to 52 weeks.
Weight loss interventions: (11 studies)
Decreases in BMI ranged from 0.2 points to 4.5 points. Weight reductions ranged from 4.8lbs to 13.2lbs (nine studies). Four out of nine studies reported significant changes in BMI between intervention and control. Five out of nine studies reported significant changes in weight between intervention and control.
Prevention of weight gain: (five studies)
Average weight gain among participants who underwent prevention programmes was 3.9lbs compared with 8.9lbs among participants in control groups (four studies); only one study reported a significant difference between intervention and control.
BMI increases were 0.7 and 0.1 points in participants in prevention programmes compared with 2.0 and 1.0 points for participants in the control groups (two studies); neither study found a significant difference between intervention and control.