Documenting adherence to psychostimulants in children with ADHD.

OBJECTIVE This study evaluates the validity, inter-rater reliability, and stability over 3 months of a semi-structured telephone interview measuring adherence to stimulant treatment, the Stimulant Adherence Measure, against the Medication Event Monitoring System (MEMS). METHODS Clinic-referred children (N=22, age 11.85 +/- 2.1 yrs) using psychostimulants for DSM-IV attention-deficit/hyperactivity disorder (ADHD) were eligible. Families used a MEMS device for the primary stimulant medication. Children and parents participated in a semi-structured telephone interview, the Stimulant Adherence Measure, for 3 consecutive months. Parent reports for previous 7 days and 28 days and child report for previous 7 days of medication use were compared to MEMS report. Inter-rater reliability and interview order were also examined. RESULTS Nineteen children and parents completed (86%). Agreement between MEMS and parent report for previous 7 days at months 1, 2 and 3 (ICC=0.829, p<0.001; ICC=0.663, p<0.05; ICC=0.878, p<0.001 respectively) and for 28 days at months 1, 2 and 3 (ICC=0.793, p<0.001; ICC=0.907, p< 0.001; ICC=0.806, p<0.001 respectively) was good to excellent. Agreement between MEMS and child report for 7 days at months 1, 2 and 3 (ICC=0.773, p<0.001, ICC=0.542, p<0.05, ICC=0.606, p<0.05 respectively) was good. Inter-rater reliability was excellent (ICC=0.956, p<0.001). There was no interview order effect for parents (F=1.771, p>0.05) or children (F=1.621, p>0.05). CONCLUSION The Stimulant Adherence Measure provides a valid and reliable method for determining stimulant medication use by children with ADHD.