Answers are grounded in this paper and cite their sources.
Randomized double-blind trial demonstrates prominent and inconsistent placebo responses in adults with ADHD, suggesting investigator ratings do not reduce placebo effects.
Objective: Several ADHD pharmacological trials reported high placebo response (PR) rates. This study aims to characterize the PR in adult ADHD. Method: A retrospective cohort analysis of the placebo arm (140 adults with ADHD, 18-55 yrs, M:F 46.4%-53.6%) of a 6-week randomized, multicenter, double-blind metadoxine study, using Conners’ Adult ADHD Rating Scale (CAARS) and the Adult ADHD Self-Report Scale (ASRS), was conducted. Results: Pre–post changes in placebo-treated adults were significant for both the CAARS and ASRS, F(2.9, 404.5) = 61.2, p < .00001, F(2.8, 383.0) = 43.1, p < .00001, respectively. Less than half of the participants had a PR which began early in treatment and persisted; almost 50% had a variable, inconsistent PR. Conclusion: In the current sample, PR in adult ADHD was prominent on both symptom scales and the investigator–rater instrument. Therefore, using investigator ratings as a primary endpoint does not necessarily attenuate PR. Of note, about half of the PR is variable, suggesting unreliable determination of efficacy.
No takes yet. Share an insight, caveat, or question.
Ben-Sheetrit et al. (2018) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: