Influence of spin in abstracts on medical students' interpretation of the results: a randomized study

Spin in research abstracts may influence readers' interpretation of study findings. We aimed to assess the impact of spin on medical students' interpretation of treatment benefit and study rigor, and to examine whether this effect differed according to study design.

We conducted a multicenter, two-arm randomized trial among fifth-year medical students from two French medical schools during the 2023-2024 academic year. Students were individually randomized to receive abstracts with or without spin from one randomized controlled trial (RCT) and one observational study. The outcomes assessed were perceived treatment benefit and perceived study rigor, both measured on a 0-10 scale. Analyses used multivariable linear mixed-effects models with a random intercept for student, including spin, study type, center, and their interaction. Generalized estimating equations were used for sensitivity analyses.

A total of 476 students provided 1,161 evaluations of perceived treatment benefit and 1,160 evaluations of perceived rigor. Spin was associated with higher perceived treatment benefit (β = 1.8; 95% CI: 1.4 to 2.1; p < 0.001). A significant interaction between spin and study type indicated a stronger effect in RCT abstracts (additional β = 2.7; 95% CI: 2.1 to 3.4; p < 0.001). Spin was not associated with perceived study rigor (β = 0.01; 95% CI: -0.29 to 0.30; p = 0.97). Results were consistent in sensitivity analyses.

Spin in abstracts influenced medical students' perception of treatment benefit, particularly for RCTs, despite formal training in critical appraisal. Perceived methodological rigor was unaffected. These findings suggest that structured training alone may not fully mitigate the interpretative impact of spin and support the development of targeted educational strategies.