Abstract: Objective The evaluation indicators of breast cancer treatment quality were used to analyze the longitudinal trend and influencing factors of breast cancer treatment quality based on the latent growth curve models(LGCM),so as to provide a basis for improving the treatment quality of breast cancer. Methods The medical records of breast cancer patients in Chinese hospitals from January 1,2021 to January 1,2023 were collected.Based on the evaluation index system for treatment quality of invasive breast cancer established by the research group in the early stage,19 evaluation indexes of breast cancer treatment quality were used to calculate the utilization rate of hospital indicators and the comprehensive scores of treatment quality.Based on LGCM,model parameters(intercept and slope)were used to evaluate the longitudinal trend of breast cancer treatment quality,and incorporate covariates into the model to evaluate their impact on the changing trend. Results The level information of 340 hospitals in China and the medical records of 104,812 breast cancer patients were obtained.Among 19 breast cancer treatment quality indicators,340 hospitals had the highest utilization rate(97.84%±9.73%)for the indicators of tumor diameter recorded in the pathological report,and the lowest utilization rate(1.91%±8.38%)for the indicators of postoperative complications;The median(quartile)of the comprehensive score for breast cancer treatment quality in the hospital was 0.475(0.348,0.596).The longitudinal trend analysis for treatment quality of breast cancer showed that the comprehensive scores for treatment quality of breast cancer in hospital showed an upward trend with time,the variance of intercept was 0.022(P＜0.001),and the variance of slope was 0.001(P＜0.001).The differences were statistically significant.The analysis of influencing factors on the trend of breast cancer treatment quality showed that the influence of the hospital region,the hospital level and the annual average number of people diagnosed and treated by the hospital on the initial comprehensive scores for treatment quality of breast cancer during the study period was statistically significant(P＜0.05),and the proportion of hospital medical insurance types was not statistically significant(P=0.307).The influence of hospital region(P=0.854),hospital level(P=0.472),the proportion of hospital medical insurance types(P=0.053),and the annual average number of hospital visits(P=0.569)on the trend of comprehensive scores of breast cancer treatment quality was not statistically significant. Conclusions In 2021,the treatment quality of breast cancer in China and the rate of change in three years are different among hospitals,and the overall trend is rising,which proves that the diagnosis and treatment process of breast cancer is constantly standardized and improved.In order to further improve the treatment quality of breast cancer,it is necessary to focus on hospitals in Western and Northern regions,secondary hospitals and hospitals with less average diagnosis and treatment of breast cancer.

Key words: breast cancer, quality of treatment, latent variable growth curve model, change trends