Waiting list may be a nocebo condition in psychotherapy trials: a contribution from network meta‐analysis

Abstract

There may be important differences in control conditions currently used in psychotherapy trials.

Neuro-Bio-Behavioral Mechanisms of Placebo and Nocebo Responses: Implications for Clinical Trials and Clinical Practice

“…However, a waiting list is a poor means of "no treatment control" because it induces a dynamic (the expectation of being treated in the near future) that differs from that in an observation study arm only (Relton et al, 2010). It has even been suggested that "waiting list" is a "nocebo" intervention, although evidence for such a worsening effect is limited to analyses that failed to take sample size into account (Furukawa et al, 2014).…”

“…Waiting controls also develop their own dynamics; on the one hand, patients may improve while waiting because of being assured of receiving active treatment soon (Beck et al, 2015), similar to the effects seen in placebo run-in phases ). On the other hand, it may be regarded as a punishment for patients not to be included in the active treatment condition (Furukawa et al, 2014). If waiting list controls are included, a "step-wedge" design may be superior, because it allows a "dose-response" assessment of waiting for treatment (Fig.…”

Efficacy of Cognitive Behavioral Therapy for Generalized Anxiety Disorder in Older Adults: Systematic Review, Meta-Analysis, and Meta-Regression

“…The use of passive control conditions in trials is fraught with limitations. For example, waitlist controls have been shown to inflate treatment effect sizes in comparison to 'no treatment' control conditions, 65 and TAU conditions are often heterogeneous reducing the generalizability of findings. 66 Only one trial 62 compared CBT to another evidence-based psychotherapy (CBT versus ACT), and so future studies certainly need to use valid active controls.…”

Personality Disorder in Childhood and Adolescence comes of Age: a Review of the Current Evidence and Prospects for Future Research

“…Hence it remains unclear to what extent the reported effects can be attributed to specific psychotherapeutic interventions (161). Of course, control treatments such as TAU or GCC should not be equated across studies, and research suggests that the choice of comparison treatment can considerably influence effect sizes in psychotherapy research (199,200), which has also been demonstrated in recent RCTs for treatments of borderline PD in adult patients (201)(202)(203)(204)(205). However, a general finding from RCTs for treatment of borderline PD in both adolescent and adult samples (206) and in reviews and metaanalyses of psychotherapy outcome research is that there is often little or no difference in efficacy among various bona fide psychotherapeutic treatments (207)(208)(209)(210); a finding commonly referred to as the Dodo bird verdict (211).…”