Abstract:

Objective: To explore case mix classification schemes and cost standards for hospitalization expenses of pulmonary tuberculosis based on Diagnosis-Related Group (DRG), providing reference for optimizing payment reform schemes for pulmonary tuberculosis. Methods: A retrospective study was conducted. Medical record information from 17829 pulmonary tuberculosis patients treated at the Shandong Provincial Public Health Clinical Center affiliated to Shandong University between January 2022 and December 2024 was collected according to inclusion criteria. Data included gender, age, medical insurance type, length of hospital stay, hospitalization costs, primary diagnosis, and other diagnoses. Univariate nonparametric tests, multiple linear regression analysis, and quantile regression analysis were performed on the hospitalization costs to identify cost thresholds. A decision tree model was then used to construct the DRG grouping scheme. Results: The average hospitalization expenses per case for the 17829 pulmonary tuberculosis inpatients ranged from 1310.91 to 86513.88 yuan, with a median (interquartile range) of 11068.43 (6932.57, 12758.35) yuan. Multivariate linear regression analysis revealed that gender, age, length of hospital stay, presence of comorbidities or complications, and drug-resistant tuberculosis status all influenced hospitalization costs. Specifically, for each additional day of hospitalization,expenses increased by 0.410 (95%CI: 0.403 to 0.418) units; hospitalization costs for non-drug-resistant tuberculosis patients were 0.664 (95%CI: -0.679 to -0.647) units lower than those for drug-resistant patients; for each one-year increase in age, costs increased by 0.052 (95%CI: 0.047 to 0.056) units; patients without comorbidities or complications incurred costs 0.086 (95%CI: -0.097 to -0.075) units lower than those with comorbidities or complications; and costs for female patients were 0.042 (95%CI: -0.052 to -0.033) units lower than those for male patients. Drug-resistant tuberculosis status, age, and length of stay were incorporated into the decision tree model, yielding a total of 14 DRG combinations and corresponding hospitalization cost standards. Among these, DRG1 (drug-resistant pulmonary tuberculosis, hospitalization duration >15 days) had the highest median standard cost of 32658.46 yuan, while DRG14 (non-drug-resistant pulmonary tuberculosis, hospitalization duration 2-7 days, age ≤30 years) had the lowest median standard cost of 6769.86 yuan. A total of 450 patients (2.52%) exceeded the upper limit of standard cost, consuming 5.12% (10106372.41/197339038.50) of medical resources, with DRG1 having the highest weight (2.98). Conclusion: The decision tree model effectively grouped inpatient costs for pulmonary tuberculosis patients, with stratification nodes consistent with regression analysis results. This cost-based grouping scheme provides a reference for controlling inpatient expenses, reducing resource consumption, and alleviating the pressure on medical insurance funds.

Key words: Tuberculosis, pulmonary, Hospitalization, Fees, medical, Tiered medical care, Cost control, Factor analysis, statistical