SynthesisInternational journal of methods in psychiatric research2003
A comparison of antidepressant trials using active and inert placebos.
Synthesis in International journal of methods in psychiatric research, 2003. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers, 4 of them syntheses that pooled 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.
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.
Who cites it
12 citing papers in PubMed, 4 syntheses or guidelines pooled it.
- Impact of active placebo controls on estimated drug effects in randomised trials: a systematic review of trials with both active placebo and standard placebo.The Cochrane database of systematic reviews · 2023Pooled it
- Inadequate description of placebo and sham controls in a systematic review of recent trials.European journal of clinical investigation · 2019Pooled it
- Pooled it
- Pooled it
- Interaction between expectancies and drug effects: an experimental investigation of placebo analgesia with caffeine as an active placebo.Psychopharmacology · 2011Trial
- Outcome Assessment in Trials of Pharmacological Treatments for Alcohol Use Disorders: Fair and Strict Testing.CNS drugs · 2019Review
- How placebo characteristics can influence estimates of intervention effects in trials.CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne · 2018Article
- Antidepressant treatment outcome depends on the quality of the living environment: a pre-clinical investigation in mice.PloS one · 2013Article
- Understanding and harnessing placebo effects: clearing away the underbrush.The Journal of medicine and philosophy · 2011Article
- Pharmacogenetic studies in depression: a proposal for methodologic guidelines.The pharmacogenomics journal · 2008Review
- Efficacy of antidepressants in adults.BMJ (Clinical research ed.) · 2005Review
- Selective serotonin reuptake inhibitors: evidence base for older antidepressants is shaky too.BMJ (Clinical research ed.) · 2005Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
1 author.
Funding
No grant is acknowledged in the PubMed record.
Abstract
In placebo-controlled antidepressant trials, there are concerns that the double blind may be breached, which may bias results. Some trials have therefore used placebos containing active substances in order to mimic the side effects of antidepressants. This study set out to examine the impact of 'unblinding' by comparing the results of a meta-analysis of a sample of trials using ordinary inert placebos with a meta-analysis of trials using active placebos. An a priori sub-group analysis of trials conducted with inpatients and outpatients was carried out. Quality was assessed using a quality assessment instrument and meta-regression analysis was conducted to explore heterogeneity. Results of meta-analysis did not differ between trials using active placebos and trials using inert ones. However, results were strongly influenced by two large trials. When these were excluded trials using inert placebos showed greater antidepressant-placebo differences than trials using active placebos. There was very high heterogeneity especially among trials using inert placebos. Meta-regression analysis showed the only significant predictor of outcome was whether trials were conducted with inpatients or outpatients. Sub-group analysis showed significant differences between antidepressants and any type of placebo in trials conducted with outpatients but not in inpatient trials. Lack of data, heterogeneity and the influence of large studies limited the analysis. The integrity of the double blind design, its effect on results and the heterogeneity between studies, require further exploration in antidepressant trials.
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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.