Quality of reporting of studies is essential to maintain accuracy and transparency. However, researchers can choose which data to report and how to report hem. Spin is defined as a specific way of reporting, implying that the beneficial effect of the experimental treatment is greater than that shown by the results. The presence of spin in research articles can negatively impact the development of further studies, clinical practice and health policies. Systematic reviews (SRs) summarize all available evidence and are the cornerstones of therapeutic evaluations. However, the interpretation of the findings is vulnerable to spin.
The aim of this systematic review is to give an overview of the prevalence of spin in SRs about robotic thoracic surgery.
To identify eligible studies Medline, EMBASE, Epistemonikos and the Centre for Reviews and Dissemination Database (University of York) were searched. SRs about robotic thoracic surgery published between 2000 and February 2020 were eligible for inclusion. The checklist published by Yavchitz et al. (2016) was used to identify spin.
Out of a total of 2480 articles, 13 thoracic surgery SRs included. Most SRs (10/13) investigated robotic surgery for lobectomy.
In 10 SRs we found spin items for misleading reporting and misleading interpretation.
In the abstract, selective reporting of, or overemphasis on efficacy outcomes favoring in the beneficial effect of the experimental intervention and a conclusion focusing selectively on statistically significant efficacy outcomes were the most frequently scored items (46%). Misleading interpretation was mostly scored as a result of a conclusion claiming equivalence, comparable effectiveness and/or safety for non-statistically significant results with a wide confidence interval (62%). Additionally, authors tend to focus on a relative effect when the absolute effect is small (62%).
In the main text, misleading reporting was mostly a result of changing the scale of the forest plot to magnify the results (54%) and a conclusion focusing selectively on statistically significant efficacy outcome (46%). Misleading interpretation was a result of focusing on a relative effect when the absolute effect is small (69%) and a conclusion claiming equivalence or comparable effectiveness (69%) or safety (54%) for non-statistically significant results with a wide confidence interval.
Our analysis suggests a high prevalence of spin in the conclusion of abstracts and main texts of SRs of thoracic robotic surgery. Misleading reporting and interpretation are the most common categories of spin. Claims for equivalence or beneficial effect of robotic thoracic surgery did not take into account factors that lower the certainty in in the evidence, like bias, imprecision and inconsistency.
Patient or healthcare consumer involvement:
Knowledge of how to identify inappropriate interpretation of the results of a SR (spin) is of importance to patients for making well-informed health care decisions.