Objective: This study investigated the effects of sluggish cognitive tempo (SCT), other psychiatric symptoms, age, dose, and pretreatment ADHD severity on methylphenidate (MPH) treatment response among ADHD children in both home and school. In addition, the predictors of the MPH-SCT treatment response were examined. Methods: One hundred eighty-five (6-12 years old) ADHD children who were treated with MPH included in the study. Results: MPH improved SCT total and SCT-Daydreaming scores both at home and school while improved SCT-Sluggish scores in only school. Higher pretreatment Daydreaming score predicted lower treatment response for inattention (B = .301, p = .002), and higher Daydreaming-Sluggish scores predicted lower treatment response for total ADHD symptoms at school (B = .456, p = .006; B = .888, p = .04, respectively). Also higher oppositional defiant disorder symptoms have negative effects on MPH treatment response in ADHD. Older age positively affected the MPH-SCT treatment response in paternal and teacher ratings. Conclusion: SCT symptoms have negative effects on MPH treatment response at school.
Keywords: ADHD; methylphenidate; sluggish cognitive tempo; treatment response.