A METAANALYSIS OF STUDIES OF THE HEALTH BELIEF MODEL WITH ADULTS

The Health Belief Model (HBM) relates a socio-psychologic theory of de cision making to individual health-related behaviors. We conducted a m eta-analysis of the relationships between four HBM dimensions (Suscept ibility, Severity, Benefits and Costs) and health behavior on 16 studi es that measured all four of the dimensions, measured a behavioral dep endent variable and included some measures of reliability, minimal cri teria for establishing the validity of the dimensions. Mean effect siz es were computed for all the studies, subgroupings representing studie s of screening, risk reduction and adherence to medical regimen, and p rospective and retrospective study designs. Of 24 mean effect sizes, 2 2 were found to be positive and statistically significant. The actual variance accounted for ranged from 0.001 to 0.09. Homogeneity was reje cted for 15 of the 22, however, suggesting that the same underlying co nstruct was not measured. Retrospective studies were found to have sig nificantly large effect sizes for benefits and costs and smaller effec t sizes for severity when compared to prospective studies. The weak ef fect sizes and lack of homogeneity indicate that it is premature to dr aw conclusions about the predictive validity of the HBM as operational ized in these studies. Our finding of only 16 studies meeting minimal criteria for valid representation of the HBM dimensions indicates that future studies should focus more on such issues.