BACKGROUND: The medical record homepage represents the core and quintessential distillation of the entire medical record. This study aims to investigate the problems with the medical record homepages data quality after the upgrade of the electronic medical record system, while simultaneously proposing practical and feasible measures to catalyze substantive improvements in data quality standards. METHODS: A retrospective analysis of data extracted from the medical record homepage system was conducted at a Chinese tertiary hospital affiliated with a medical university between January and December 2021. Analysis of Moment Structures (AMOS) was used to construct a structural equation model, with the aim of elucidating the influence of individual variables on dependent variables. Furthermore, a fish bone diagram analysis was utilized to systematically analyze the underlying causes of quality defects. RESULTS: Among the 2,731 medical record homepages subjected to scrutiny, a substantial proportion of 1,531 records (56.1%) exhibited quality issues. The structural equation model revealed that patient demographic information exerted the most profound influence on data quality, as evidenced by the greatest value of the standardized total effects (β = -0.729), followed by surgery (β = -0.606) and diagnosis information (β = -0.363). Moreover, the fish-bone diagram analysis was employed to systematically dissect the underlying causes of quality defects in the medical record homepages, encompassing human factors, surroundings, regulatory system, and machinery. CONCLUSIONS: The predominant factor contributing to the poor data on the medical record homepage was inaccuracies in demographic information, closely followed by errors in surgical and diagnosis information. It is helpful to improve the data quality of the medical record homepages by establishing a coder qualification certification system, strengthening the construction of medical informatization, and adding data validation and prompt functions.