A meta-analytic evaluation of couples weight-loss programs.

Applied Hedges and Olkin's (1985) statistical meta-analytic procedures to summary data from all published studies that compared behavioral weight-control programs that formally involved partners in treatment (couples programs) to similar programs in which subjects participated alone (subject-alone programs). Based on tests of effect sizes, couples programs are significantly superior to subject-alone programs at posttreatment (p less than .05). A nearly significant (p = .06) statistical superiority for couples programs versus subject-alone programs is also found at 2- to 3-month follow-up, but not thereafter. The couples programs differed in the kinds of social support provided by partners, and the most productive kinds of partner support remain to be identified. In particular, the use of partners in providing social support to subjects after formal therapy has ended is still an area of largely unexplored potential.