Evidence map›Paper›PMID 34355753›Full record

SynthesisThe international journal of neuropsychopharmacology2022

Placebo Response and Its Predictors in Attention Deficit Hyperactivity Disorder: A Meta-Analysis and Comparison of Meta-Regression and MetaForest.

Xavier Castells, Marc Saez, Maghie Barcheni, Ruth Cunill, Domènec Serrano, Beatriz López, Caspar J van Lissa

Abstract readMeta-AnalysisSystematic Review
PubMed Full text at PMC Publisher
In one paragraph

Synthesis in The international journal of neuropsychopharmacology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers, 3 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
9citing papers in PubMed, 3 pooled it
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

9 citing papers in PubMed, 3 syntheses or guidelines pooled it.

  1. Pooled it
  2. Pooled it
  3. Pooled it
  4. Trial
  5. Trial
  6. Article
  7. Review
  8. Predictors of placebo response in three large clinical trials of the V1a receptor antagonist balovaptan in autism spectrum disorder.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2023
    Article
  9. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Xavier CastellsTransLab Research Group, Universitat de Girona, Girona, Spain.ORCID 0000-0002-2619-7273
Marc SaezCentre for Biomedical Research Network in Epidemiology and Public Health (CIBERESP), Madrid, Spain.ORCID 0000-0003-1882-0157
Maghie BarcheniPharmacology, Toxicology and Therapeutics Department, Universitat Autònoma de Barcelona, Barcelona, Spain.
Ruth CunillParc Sanitari Sant Joan de Déu-Numància, Parc Sanitari Sant Joan de Déu, Barcelona, Spain.
Domènec SerranoDepartment of Medical Sciences, Universitat de Girona, Girona, Spain.
Beatriz LópezControl and Intelligent Systems Engineering Research Group, Electrical; Electronic and Automatic Engineering Department, Universitat de Girona, Girona, Spain (Dr López).ORCID 0000-0001-9210-0073
Caspar J van LissaDepartment of Methodology and Statistics, Universiteit Utrecht, Utrecht, The Netherlands (Dr van Lissa).

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundHigh placebo response in attention deficit hyperactivity disorder (ADHD) can reduce medication-placebo differences, jeopardizing the development of new medicines. This research aims to (1) determine placebo response in ADHD, (2) compare the accuracy of meta-regression and MetaForest in predicting placebo response, and (3) determine the covariates associated with placebo response.

methodsA systematic review with meta-analysis of randomized, placebo-controlled clinical trial investigating pharmacological interventions for ADHD was performed. Placebo response was defined as the change from baseline in ADHD symptom severity assessed according to the 18-item, clinician-rated, DSM-based rating scale. The effect of study design-, intervention-, and patient-related covariates in predicting placebo response was studied by means of meta-regression and MetaForest.

resultsNinety-four studies including 6614 patients randomized to placebo were analyzed. Overall, placebo response was -8.9 points, representing a 23.1% reduction in the severity of ADHD symptoms. Cross-validated accuracy metrics for meta-regression were R2 = 0.0012 and root mean squared error = 3.3219 for meta-regression and 0.0382 and 3.2599 for MetaForest. Placebo response among ADHD patients increased by 63% between 2001 and 2020 and was larger in the United States than in other regions of the world.

conclusionsStrong placebo response was found in ADHD patients. Both meta-regression and MetaForest showed poor performance in predicting placebo response. ADHD symptom improvement with placebo has markedly increased over the last 2 decades and is greater in the United States than the rest of the world.

Indexed as

Placebo EffectAdolescentAdultAttention Deficit Disorder with HyperactivityCentral Nervous System StimulantsHumansMaleRandomized Controlled Trials as TopicTreatment OutcomeUnited StatesCentral Nervous System StimulantsAttention Deficit Hyperactivity Disordermachine learningmeta-analysisMetaForestmeta-regressionplacebo response

Identifiers

PMID34355753
PMCPMC8756096

What OpenQuestion holds

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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.