"Spin" refers to misleading reporting, interpretation, and extrapolation of findings in primary and secondary research (such as in systematic reviews). The study of spin primarily focuses on beneficial outcomes. The objectives of this research were threefold: first, to develop a framework for identifying spin associated with harms in systematic reviews of interventions; second, to apply the framework to a set of reviews, thereby pinpointing instances where spin may be present; and finally, to revise the spin examples, offering guidance on how spin can be rectified.
The authors developed their framework through an iterative process that engaged an international group of researchers specializing in spin and reporting bias. The framework comprises 12 specific types of spin for harms, grouped by 7 categories across the 3 domains (reporting, interpretation, and extrapolation). The authors subsequently gathered instances of spin from a random sample of 100 systematic reviews of interventions. Of the 58 reviews that assessed harm and the 42 that did not, they found that 28 (48%) and 6 (14%), respectively, had at least 1 of the 12 types of spin for harms. Inappropriate extrapolation of the results and conclusions for harms to populations, interventions, outcomes, or settings not assessed in a review was the most common category of spin in 17 of 100 reviews.
The authors revised the examples to remove spin, taking into consideration the context (for example, medical discipline, source population), findings for harms, and methodological limitations of the original reviews. They provide guidance for authors, peer reviewers, and editors in recognizing and rectifying or (preferably) avoiding spin, ultimately enhancing the clarity and accuracy of harms reporting in systematic review publications.