Using theory to develop and test interventions to promote changes in health behaviour: evidence, issues, and recommendations

Using theory to develop health behaviour interventions provides a useful framework to accumulate evidence and has been associated with larger changes in health behaviour. The present review suggests, however, that the evidence that using theory in this way produces greater health behaviour change is mixed. Furthermore, evaluating such evidence is difficult because: first, a significant proportion of interventions are not based on theory; second, those that are, tend not to apply the theory extensively; third, theory-based and comparison groups can be confounded; and fourth, interventions may be based on multiple theories. Such difficulties delay theory evolution and the development of interventions that are capable of achieving significant and sustained changes in health behaviours. Recommendations are made to address these issues.