Abstract: Objective  To analyze the reporting quality and impact factors of postgraduate dissertations using case-control study design and provide a basis for optimizing the teaching of “Clinical Epidemiology” and further improving the quality of dissertations. Methods  The theses of medical students with case-control study design included in CNKI and Wanfang Data Resource system from 2016 to 2020 were randomly selected, and the quality of their reports and influencing factors were evaluated based on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE). Results  Total  260 dissertations were finally included, with an average (standard deviation) items total reporting rate of 65.6% (±10.1%). There were important items missing in Methods and Results sections. Items with a lower reporting rate involved relative risk transformation, description of reasons for withdrawal of research subjects, flowchart of subject inclusion, strategies for missing data processing and sensitivity analysis, and sample size estimation. It suggests that there may be more defects in the research design. It suggests that the study design may be flawed; The dissertations with a later year of publication and authors majoring in public health and preventive medicine had a significant increased average total reporting rate. Conclusion  The findings suggested the quality of case-control study reports in postgraduate dissertations needs to be further improved, and the teaching of Clinical Epidemiology should be improved based on cases and STROBE guideline.

Key words: STROBE guideline, postgraduate dissertation, case-control study, reporting quality