A meta-analysis of the health action process approach.

Objective The health action process approach (HAPA) is a social-cognitive model specifying motivational and volitional determinants of health behavior. A meta-analysis of studies applying the HAPA in health behavior contexts was conducted to estimate the size and variability of correlations among model constructs, test model predictions, and test effects of past behavior and moderators (behavior type, sample type, measurement lag, study quality) on model relations. Method A literature search identified 95 studies meeting inclusion criteria with 108 independent samples. Averaged corrected correlations among HAPA constructs and multivariate tests of model predictions were computed using conve…