Patient Experience and Predictors of Improvement in a Group Behavioral and Educational Intervention for Individuals With Diabetes and Serious Mental Illness: Mixed Methods Case Study

BACKGROUND: In a previous study, participation in a 16-week reverse integrated care and group behavioral and educational intervention for individuals with diabetes and serious mental illness was associated with improved glycemic control (hemoglobin A(1c)) and BMI. To inform future implementation efforts, more information about the effective components of the intervention is needed. OBJECTIVE: The goal of this study is to identify the aspects of the intervention participants reported to be helpful and to evaluate the predictors of outcomes. METHODS: This study involved qualitative evaluation and post hoc quantitative analysis of a previous intervention. Qualitative data were collected using semistructured interviews with 69% (24/35) of the individuals who attended 1 or more group sessions and 35% (9/26) of the individuals who consented but attended no sessions. Quantitative mixed effects modeling was performed to test whether improved diabetes knowledge, diet, and exercise or higher group attendance predicted improved hemoglobin A(1c) and BMI. These interview and modeling outcomes were combined using a mixed methods case study framework and integrated thematically. RESULTS: In qualitative interviews, participants identified the application of health-related knowledge gained to real-world situations, accountability for goals, positive reinforcement and group support, and increased confidence in prioritizing health goals as factors contributing to the success of the behavioral intervention. Improved knowledge of diabetes was associated with reduced BMI (β=–1.27, SD 0.40; P=.003). No quantitative variables examined were significantly associated with improved hemoglobin A(1c) levels. CONCLUSIONS: In this mixed methods analysis of predictors of success in a behavioral diabetes management program, group participants highlighted the value of positive reinforcement and group support, accountability for goals set, and real-world application of health-related knowledge gained. Improved diabetes knowledge was associated with weight loss.