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Why prudence is needed when interpreting articles reporting clinical trial results in mental health
Rafael Dal-Ré1, Julio Bobes2,3, Pim Cuijpers4,5
1Clinical Research, BUC (Biosciences UAM+CSIC) Program, International Campus of Excellence, Universidad Autónoma de Madrid, Ciudad Universitaria de Cantoblanco, c/Einstein 3, 28049, Madrid, Spain. rfdalre@gmail.com.
Background:
Clinical trial results' reliability is impacted by reporting bias. This is primarily manifested as publication bias and outcome reporting bias.
Mental Health Trials' Specific Features:
Mental health trials are prone to two methodological deficiencies: (1) using small numbers of participants that facilitates false positive findings and exaggerated size effects, and (2) the obligatory use of psychometric scales that require subjective assessments. These two deficiencies contribute to the publication of unreliable results. Considerable reporting bias has been found in safety and efficacy findings in psychotherapy and pharmacotherapy trials. Reporting bias can be carried forward to meta-analyses, a key source for clinical practice guidelines. The final result is the frequent overestimation of treatment effects that could impact patients and clinician-informed decisions.
Mechanisms To Prevent Outcome Reporting Bias:
Prospective registration of trials and publication of results are the two major methods to reduce reporting bias. Prospective trial registration will allow checking whether they are published (so it will help to prevent publication bias) and, if published, whether those outcomes and analyses that were deemed as appropriate before trial commencement are actually published (hence helping to find out selective reporting of outcomes). Unfortunately, the rate of registered trials in mental health interventions is low and, frequently, of poor quality.
Conclusion:
Clinicians should be prudent when interpreting the results of published trials and some meta-analyses - such as those conducted by scientists working for the sponsor company or those that only include published trials. Prescribers, however, should be confident when prescribing drugs following the summary of product characteristics, since regulatory agencies have access to all clinical trial results.
Insights
Reporting bias, including publication and outcome reporting bias, undermines clinical trial reliability, especially in mental health research. Strategies like prospective trial registration are crucial but underutilized to ensure accurate treatment effect reporting.
Area of Science:
- Clinical research methodology
- Psychotherapy and pharmacotherapy trials
- Evidence-based medicine
Background:
- Reporting bias, encompassing publication bias and outcome reporting bias, significantly compromises the reliability of clinical trial results.
- Mental health trials face unique challenges, including small sample sizes and reliance on subjective psychometric scales, exacerbating the risk of unreliable findings.
- This bias can propagate into meta-analyses, influencing clinical practice guidelines and leading to an overestimation of treatment effects.
Discussion:
- Reporting bias in mental health research leads to the publication of unreliable results, affecting psychotherapy and pharmacotherapy trials.
- The deficiencies in mental health trials, such as small participant numbers and subjective assessments, contribute to exaggerated effect sizes and false positive findings.
- Reporting bias can distort meta-analyses, impacting clinical practice guidelines and patient care decisions.
Key Insights:
- Prospective trial registration and result publication are vital for mitigating reporting bias.
- Prospective registration helps verify publication and prevent selective reporting of outcomes.
- Current rates of prospective trial registration in mental health interventions are low and often of poor quality.
Outlook:
- Clinicians must exercise caution when interpreting published trial and meta-analysis results, particularly those sponsored by companies or limited to published data.
- Prescribers can rely on drug summaries of product characteristics due to regulatory access to all trial data.
- Improving trial registration rates and quality is essential for enhancing the trustworthiness of mental health research findings.
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