SPIN in systematic reviews on the management of caries lesions in children and adolescents: a meta-research

SPIN, or distortion bias, is the intentional or unintentional interpretation of research results in a way that suggests favorable or unfavorable conclusions without adequate justification, which can compromise the validity of the evidence and mislead clinical recommendations. This meta-research assessed the presence, prevalence, and nature of SPIN in systematic reviews on the management of caries lesions in children and adolescents (0–18 years), and its association with journal endorsement of the PRISMA guidelines. The protocol was registered on the Open Science Framework (OSF) on 30 October 2024 (https://doi.org/10.17605/OSF.IO/6Y4EM). MEDLINE (PubMed), Embase, Cochrane Library, ProQuest, and LILACS were searched without restriction. Two independent, calibrated reviewers selected the studies and extracted data on bibliometric, methodological, guideline-conformity, and conflict-of-interest characteristics. Following the criteria of Yavchitz et al. (2016), adapted by Sensever et al. (2022), SPIN was identified separately in the abstract and full text and graded as low, moderate, or high according to the failure to acknowledge non-significant results, the absence of uncertainty, and the lack of a recommendation for further studies. The SPIN–PRISMA association was tested with the chi-square test (α = 5%). Fifty-three systematic reviews were included. SPIN was identified in 66% of abstracts and 52.8% of full texts, with no significant association with PRISMA endorsement. The interpretive component of SPIN assessment and the restriction to caries-management reviews limit generalization. SPIN is frequent in systematic reviews, especially in abstracts, suggesting that formal PRISMA endorsement alone does not ensure unbiased reporting and reinforcing the need for rigorous methodology, transparent reporting, and critical appraisal in he management of carious lesions in children and adolescents.