Understanding family-level motivational factors in pediatric weight management is helpful clinically since both youth and parents play important roles in lifestyle change.

To pilot test and conduct preliminary analyses to determine the convergent and predictive validity of the Readiness and Motivation Interview for Families (RMI-Family), a structured interview.

Our study included 13-17 year olds with overweight or obesity and their parents from pediatric weight management clinics in Edmonton and Calgary. Using the RMI-Family, motivation-related constructs were assessed (5-point Likert scale) in youth and parents separately for exercise, screen time, sleep, treat foods, overeating, and emotional eating. Participants completed the interview twice (3 months apart); interviewers were trained in motivational interviewing. Anthropometric and sociodemographic data were also collected.

Data from 10 families were collected (youth: 6 girls, 4 boys; 15.7±2.1 years old; BMI z-score: 2.02±0.68; parents: 8 mothers, 2 fathers; 48.8±6.4 years old; BMI: 30.0±8.3 kg/m2). At time 1, youth and parents rated the highest motivation to change to increase sleep and decrease intake of treat foods, respectively. We found positive correlations between youth and parent motivation to change sleep (r=0.72; p=0.02) and overeating (r=0.74; p=0.014). Youth motivation to change emotional eating was positively associated with readiness to change that habit both at times 1 and 2 (r=0.72; p=0.019 and r=0.67; p=0.049). Parent motivation to change youth overeating decreased between times 1 and 2 (F=6.9; p=0.031), but no other differences were detected in youth and parent motivation scores between times 1 and 2 (all p>0.05).

In both youth and parents, the RMI-Family generated relatively reliable ratings of motivational constructs over time. Our research remains ongoing and will include additional psychometric analyses (e.g., concurrent validity).

The RMI-Family has the potential to help healthcare professionals assess and monitor motivational constructs in families enrolled in pediatric weight management.