The Impact of Spin on the Interpretations of Abstracts of Randomized Controlled Trials in the Field of Clinical Psychology: An Online Randomized Controlled Trial

ABSTRACTObjectives To assess the impact of spin on the interpretation of the results and conclusions reported in abstracts describing randomized controlled trials investigating behavioural treatments for depression. Design This study was an online parallel-group randomized controlled trial. Participants We recruited clinicians and clinical researchers by sending 6794 email invitations. We received 190 eligible responses of which 91 were randomized into the ‘without spin’-condition and 99 into the ‘with spin’-condition. Interventions We selected 10 abstracts from published RCTs that investigated behavioural treatments for depression. The RCTs had at least one nonsignificant primary outcome and an abstract conclusion that claimed a beneficial effect despite that nonsignificant primary outcome. We rewrote the abstracts to create a spinless version of each of the 10 abstracts. Participants were randomly assigned to read one version of one of the 10 abstracts and answer questions about the study described in the abstract. Outcome measures The primary outcome was the participants’ perception of the effectiveness of the treatment proposed in the abstract, rated on a scale from 0 to 10. Results The Bayesian analysis showed no convincing support for an effect of spin on the participants’ perception of the treatment effectiveness (posterior mean = 0.53, SE = 0.27, 95% CI [-0.01, 1.07]; posterior mode = 0.54, 95% HDI [-0.02, 1.06]). However, following the Bayes factor of 1.8, no convincing support for a null-effect was found either.Conclusion The presence of spin in abstracts did not convincingly impact the perceptions of clinicians and clinical researchers regarding the effectiveness of the proposed treatment.