Dose-Response Effects of Methylphenidate on Ecologically Valid Measure of Academic Performance and Classroom Behavior in Adolescents with ADHD

By: Stephen Evans, William Pelham, Bradley Smith, and Oscar Bukstein, et al.

Purpose of study

Many have asked if medications such as Ritalin (methylphenidate) improve academic achievement in children and adolescents with ADHD. Studies document changes in behavior but little research has addressed improvement in academic achievement using standardized tests of achievement. Additionally, some research suggests that dosage may affect outcome.For example, higher doses may improve behavior: lower, cognitive performance.This study attempts to assess both of these questions. This study also addresses the question of ADHD in adolescents. Few studies to date have addressed this question.


45 adolescents (40 male and 5 females) participated in the study. All had a primary diagnosis of ADHD.The adolescents were took part in a summer treatment program for adolescents at Eastern Psychiatric Institute and Clinic at the University of Pittsburgh Medical Center. How study was done: Classroom behaviors were defined and students had time to work at school to complete assignments. Medications were given in different doses and in a placebo (a pill with no medication) to the students beginning in the third week in the program.


  1. How was improvement measured?
    1. Measures of academic performance were percentages of main ideas and details about a history lesson that adolescents recorded in notebooks. Daily history worksheets and quizzes were also scored.
    2. Measures of behavior included observations of on task behavior and disruptive behavior.
  2. Specific results
    1. Group results found significant effects and improvement for all measures in all medication conditions when compared to the placebo condition, to the condition where the pill contained no medication.
    2. Most adolescents in the study also individually showed improvement. Highest doses of Ritalin, however, were not always the most effective.
    3. Improvement in behavior could not be documented since there was a ceiling effect. Due perhaps to the structured nature of the classroom the adolescents did not demonstrate significant disruptive behavior. This means that improvement in behavior was more difficult to document.

Bottom line

Before relying on the results of this study as evidence that medication significantly improve academic achievement, it is important to read the entire study. Sample size is relatively small, classroom structure may not approximate most classrooms, measures of improved achievement are not standardized tests of achievement that can document improvement over time. Parents and students in the study also received individualized training on how to study or help a student study and how to effectively benefit from class materials. It is important to note that the highest dose of medication was not always the most effective.

The results of this study suggest that it is very important for parents to work closely with the professional who is prescribing medication to be certain that dosage, learning environment and family support are combined to help a student maximize academic and social success.

Experimental and Clinical Psychopharmacology, (2001)