Over-interpretation of findings in diagnostic accuracy studies of infectious diseases.

Objectives: To assess the prevalence of overly positive interpretation, also called 'spin',-of results in diagnostic accuracy studies of infectious diseases and to identify suggestions for improvement.

Methods: A PubMed search was performed to identify diagnostic accuracy studies of infectious diseases published between January and March 2019. Each article was assessed by two authors independently to identify study characteristics and forms of actual and potential over-interpretation. 'Actual over-interpretation' was defined as conclusions that were not on the basis of study aims or conclusions that were more favourable than justified by the study findings. There are other practices that may result in the over-interpretation of study findings and these have been described as 'potential over-interpretation'.

Results: The final analysis included 120 studies. Favourable or promising recommendations were made in the main text of 101 (84%) of the included studies. Evidence of actual over-interpretation (spin) was found in 30 (25%) articles, with 22 (18%) studies reporting a conclusion that did not match the study aims and 56 (47%) studies with a more positive conclusion in the abstract than the main text. All analysed studies exhibited at least one form of potential over-interpretation, with was most commonly a lack of sample size calculation (n = 109, 91%) and not reporting a null hypothesis (n = 115, 96%).

Discussion: Evidence of over-interpretation of results was found in one-third of the included studies. We have proposed possible interventions to prevent overly positive interpretations of results in diagnostic accuracy studies.