Game, Set, and Match: A Scoping Review of Matching Characteristics for Control and Intervention Groups in Adaptive...

Behavioral interventions targeting physical activity and/or healthy eating are often used for weight regulation, and adaptive intervention designs that personalize the dosage based on individuals' responses to the intervention components may optimize impact. However, little research has examined how best to design/optimize non-pharmacological adaptive weight regulation trials, and decisions regarding selection/use of control groups in these trials are less clear. This scoping review aimed to identify and describe study and participant characteristics reported and/or used to match intervention and control groups within non-pharmacological, adaptive behavioral weight regulation interventions. Systematic search of adaptive interventions targeting physical activity/healthy eating for weight regulation was conducted following PRISMA-ScR guidelines. Study and participant characteristics reported and/or matched between groups were independently extracted and coded. Of 1,431 articles screened, 4.4% met the inclusion criteria. Study designs were protocol/rationale/design papers (43%), randomized control trials (40%), and pilot/feasibility trials (17%). Most (73%) had a control/comparison condition; 100% matched measurement protocols and dosage exposure. Many (51%) reported participant characteristics (e.g., age, body mass index [BMI]), but only 35% of studies used these as matching factors. Some studies (35%) matched groups on content. These findings illustrate that most adaptive weight control interventions matched the groups based on study characteristics (e.g., measures) but few used participant characteristics (e.g., BMI) despite potential moderating influences on weight regulation. This is an important gap in the literature, and future research is needed to explore the extent to which individual participant characteristics in non-pharmacological adaptive weight control interventions impact dosage efficacy/effectiveness.