Objective versus subjective assessment of methylphenidate response
Iris Manor1, Sheera Meidad, Gil Zalsman
1ADHD Unit, Geha Mental Health Center, P.O. Box 102, Petach Tikva, 49100, Israel. imanor@clalit.org.il
Child Psychiatry and Human Development
|December 7, 2007
Summary
Subjective reports of methylphenidate (MPH) effectiveness in children with attention deficit/hyperactivity disorder (ADHD) do not reliably predict performance on the Test-of-Variables-of-Attention (TOVA). Objective measures are crucial for assessing MPH benefits in pediatric ADHD.
Area of Science:
- Neuroscience
- Child and Adolescent Psychiatry
- Pharmacology
Background:
- Attention deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder.
- Methylphenidate (MPH) is a frequently prescribed stimulant medication for ADHD.
- Assessing treatment efficacy in pediatric ADHD is critical for optimizing patient outcomes.
Purpose of the Study:
- To compare subjective self-perception of improvement with objective performance measures after a single dose of MPH in children with ADHD.
- To evaluate the reliability of the Clinical Global Impression-Change (CGI-C) scale against the Test-of-Variables-of-Attention (TOVA) in assessing MPH response.
Main Methods:
- 165 children and adolescents (aged 5-18) diagnosed with ADHD participated.
- Participants received a single dose of MPH (0.3 mg/kg).
- Subjective improvement was measured using the CGI-C scale, while objective performance was assessed using the TOVA before and after MPH administration.
Main Results:
- A significant inverse correlation was observed between CGI-C scores and TOVA-Commission scores (r = -0.326, p < 0.001).
- This indicates that subjective reports of improvement did not align with objective performance changes on the TOVA.
- The findings suggest a disconnect between patient-reported outcomes and objective cognitive performance.
Conclusions:
- Subjective reports, such as those from the CGI-C scale, are unreliable for assessing the benefits of MPH in pediatric ADHD populations.
- Objective cognitive assessments like the TOVA are essential for accurately evaluating MPH efficacy.
- Future research should focus on integrating both subjective and objective measures for a comprehensive understanding of treatment response in ADHD.
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