Do Single and Multiple Behavior Change Interventions Contain Different Behavior Change Techniques? A Comparison of Interventions Targeting Physical Activity in Obese Populations

Objective: Interventions to increase physical activity (PA) can target this behavior alone or as part of multiple health behavior change (MHBC) interventions. To date, little is known about the content of MHBC interventions compared with single health behavior change (SHBC) interventions. This study sought to compare the number and type of behavior change techniques (BCTs) in SHBC and MHBC interventions using a secondary analysis of studies included in a systematic review of PA interventions in obese populations. Methods: BCTs used to increase PA (PA BCTs) in intervention descriptions of included studies were double coded using a standardized BCT taxonomy. Interventions were categorized as SHBC (targeting PA) or MHBC (targeting PA and diet) interventions. The mean number of PA BCTs for SHBC and MHBC interventions was compared using an independent-samples t test. Chi-square analyses for each BCT assessed differences in proportions of SHBC and MHBC interventions that contained that BCT. Results: The MHBC obesity interventions contained a greater number of PA BCTs (M = 11.68) than the SHBC obesity interventions (M = 8.71). Six PA BCTs were more common in MHBC interventions. Two PA BCTs were more common in the SHBC interventions. Conclusions: SHBC and MHBC interventions may systematically differ not only in the number of behaviors targeted, but also in the numbers and type of BCTs used. This study demonstrates that intervention content should also be considered when assessing the relative effectiveness of SHBC and MHBC interventions.