The meta-analysis by Quinn and Fromme (2011) is reviewed and integrated into the larger field. Guidelines for future research are presented.

With results of the meta-analysis along with those of a recent comprehensive prospective study by our group (King et al., 2011), there is a call to the field to specify terms and integrate theoretical frameworks to advance our knowledge and improve comparisons across trials.

The meta-analysis is both timely and thorough and will provide clinical researchers with important information to move the field forward.