Background: This study aimed to describe the development and psychometric evaluation of novel youth and parent measures of self-efficacy related to continuous glucose monitoring (CGM) in pediatric patients with type 1 diabetes. This evaluation also assessed the predictive validity of the CGM Self-Efficacy (CGM-SE) surveys on CGM use and hemoglobin A1c (HbA1c) levels.
Subjects and methods: Study participants included 120 youth with type 1 diabetes for ≥1 year enrolled in a 2-year randomized clinical trial comparing CGM use with and without the addition of a family-focused CGM behavioral intervention. Youth and parents completed the CGM-SE surveys at randomization after a 1-week run-in to assess CGM tolerability. Analyses of predictive validity excluded the intervention group and included 61 youth in the control group in order to assess CGM use and HbA1c outcomes 3 and 6 months after randomization.
Results: At study entry, youth were 12.7±2.7 years old with a diabetes duration of 6.1±3.6 years and an HbA1c level of 8.0±0.8% (64±9 mmol/mol); blood glucose monitoring frequency was 6.8±2.4 times/day, and 84% received pump therapy. CGM-SE surveys had acceptable internal consistency (Cronbach's α=0.80 for youth and 0.82 for parents). Youth reporting higher baseline CGM self-efficacy (CGM-SE score of >80) had significantly greater CGM use and lower HbA1c level after 3 and 6 months compared with youth reporting lower baseline CGM self-efficacy (CGM-SE score of ≤80).
Conclusions: The CGM-SE surveys appear to have strong psychometric properties. CGM self-efficacy may offer an opportunity to assess the likelihood of CGM adherence and glycemic improvement in youth with type 1 diabetes in clinical and research settings.