The risk of bias - symptom and performance validity (RoB-spv): a risk of bias checklist for systematic review and meta-analysis.

Objective: The analysis of risk of bias in systematic reviews (SR) and meta-analyses (MA) is a fundamental task to ensure the correct synthesis of results. To carry out this task, specific tools must be used for each research design of the studies analyzed. The choice of an appropriate tool is currently a challenge for researchers developing SR and MA in the area of symptom and performance validity because the research designs used have been created specifically for this field. Although these designs can be integrated within the classic classifications, they present a number of particular characteristics that are not reflected in any of the current risk of bias analysis tools. The aim of this study is to design a checklist specifically for systematic review/meta-analysis focused on validity tests. Methods: The checklist was developed through objective review of the existing evidence, development of checklist items, and refinement by external feedback and performance analysis. Results: The checklist is composed of four sections: Clinical comparison group selection, sources of bias in either simulation or criterion group designs, and overall assessment of the study. Inter-rater reliability was assessed with a sample of 20 studies, resulting in good to excellent intraclass correlation coefficients for most items. Conclusions: The checklist seeks to fill an important gap in the literature by serving as an assessment tool that improves the reliability of evidence synthesis in symptom and performance validity studies. This instrument facilitates the development of SR and MA that meet international standards, improving methodological rigor and reliability in the forensic setting.