Biases in research: risk factors for non-replicability in psychotherapy and pharmacotherapy research

  title={Biases in research: risk factors for non-replicability in psychotherapy and pharmacotherapy research},
  author={Falk Leichsenring and Allan A. Abbass and Mark Hilsenroth and F. Markus Leweke and Patrick Luyten and John R. Keefe and Nicolas Midgley and Sven Rabung and Simone Salzer and Christiane Steinert},
  journal={Psychological Medicine},
Replicability of findings is an essential prerequisite of research. For both basic and clinical research, however, low replicability of findings has recently been reported. Replicability may be affected by research biases not sufficiently controlled for by the existing research standards. Several biases such as researcher allegiance or selective reporting are well-known for affecting results. For psychotherapy and pharmacotherapy research, specific additional biases may affect outcome (e.g… 
Methodological issues in psychological treatment research : applications to gambling research and therapist effects
Over the last couple of decades evidence-based psychotherapies have flourished, and there are now therapies that are well-established for a wide range of problems. At the same time the mental-health
Cochrane’s risk of bias tool in the context of psychotherapy outcome research
  • T. MunderJ. Barth
  • Psychology
    Psychotherapy research : journal of the Society for Psychotherapy Research
  • 2018
The rationale of a widely used tool to assess the methodological quality of primary studies for meta-analysis is discussed and suggestions for its use in the context of psychotherapy outcome research are provided.
Statistical power in clinical trials of interventions for mood, anxiety, and psychotic disorders
Power to detect both fixed and meta-analytic effect sizes in clinical trials in psychiatry was low across all interventions and disorders examined, confirming the need to increase sample sizes and to reduce reporting bias against studies reporting null results to improve the reliability of the published literature.
The New Caucus-Race: Methodological Considerations for Meta-Analyses of Psychotherapy Outcome
The Dodo Bird Verdict (DBV)—the proposition that all psychotherapies are equally effective—remains bitterly contested by researchers, who have mainly used meta-analyses as the primary tool to
The efficacy of psychotherapies and pharmacotherapies for mental disorders in adults: an umbrella review and meta‐analytic evaluation of recent meta‐analyses
After more than half a century of research, thousands of RCTs and millions of invested funds, the effect sizes of psychotherapy and pharmacotherapies for mental disorders are limited, suggesting a ceiling effect for treatment research as presently conducted.
Psychodynamic Therapy: As Efficacious as Other Empirically Supported Treatments? A Meta-Analysis Testing Equivalence of Outcomes.
Results suggest equivalence of psychodynamic therapy to treatments established in efficacy is suggested, and who benefits most from which treatment is examined.
Treatment Refusal and Premature Termination in Psychotherapy, Pharmacotherapy, and Their Combination: A Meta-Analysis of Head-to-Head Comparisons
Differences in refusal rates for pharmacotherapy and psychotherapy were particularly evident for depressive disorders, panic disorder, and social anxiety disorder and providers of these treatments should seek to employ strategies to reduce their occurrence.
The Research-Practice Psychotherapy Wars: The Case of Group Psychotherapy in the Treatment of PTSD
ABSTRACT In light of two recent meta-analyses of the efficacy of group psychotherapy in treating posttraumatic stress disorder (PTSD), this article critically reviews the randomized control trial
Bias Toward Psychodynamic Therapy: Framing the Problem and Working Toward a Solution.
Current evidence for PDT is summarized, existing biases are described, and a set of recommendations are formulated to foster a more balanced perspective on PDT.


Researcher allegiance in psychotherapy outcome research: an overview of reviews.
Efficacy of cognitive–behavioural therapy and other psychological treatments for adult depression: meta-analytic study of publication bias
The effects of psychotherapy for adult depression seem to be overestimated considerably because of publication bias.
Disclosure of researcher allegiance in meta-analyses and randomised controlled trials of psychotherapy: a systematic appraisal
Stringent guidelines should be adopted by journals in order to improve reporting and attenuate possible effects of RA in future research, though meta-analyses perform slightly better than RCTs.
Psychotherapist effects in meta-analyses: How accurate are treatment effects?
Reexamining meta-analyses that found statistically significant differences between treatments for a variety of disorders by correcting the treatment effects according to the variability in outcomes known to be associated with psychotherapists demonstrated that after adjusting the results based on most small estimates of therapist effects, ∼80% of the reported treatment effects would still be statistically significant.
Can psychotherapists function as their own controls? Meta-analysis of the crossed therapist design in comparative psychotherapy trials.
Results suggest that researchers strongly allied to a treatment may ignore therapist allegiance, potentially skewing outcomes, and all clinical trials, and especially crossed therapist designs, should measure psychotherapist allegiance to evaluate this possible bias.
Is the allegiance effect an epiphenomenon of true efficacy differences between treatments? a meta-analysis.
This study does not support the true efficacy hypothesis, which predicted the RA-outcome association to be zero; however, a substantial association was found and was found to be a significant predictor of outcome and explained 12% of the variance in outcomes.
Psychodynamic therapy meets evidence-based medicine: a systematic review using updated criteria.
Does Publication Bias Inflate the Apparent Efficacy of Psychological Treatment for Major Depressive Disorder? A Systematic Review and Meta-Analysis of US National Institutes of Health-Funded Trials
The efficacy of psychological interventions for depression has been overestimated in the published literature, just as it has been for pharmacotherapy, and funding agencies and journals should archive both original protocols and raw data from treatment trials to allow the detection and correction of outcome reporting bias.
A quality-based review of randomized controlled trials of psychodynamic psychotherapy.
It would be sufficient to make psychodynamic psychotherapy an "empirically validated" treatment only if further randomized controlled trials of adequate quality and sample size replicated findings of existing positive trials for specific disorders.
Testing the allegiance bias hypothesis: A meta-analysis
The results support the view that RA acts as a bias in treatment comparisons, and differences in the conceptual quality of treatments mediated the effect of RA on outcome.