Table 1.

Baseline characteristics of the study population stratified by 30-day readmission status.

Variable	No readmission (N = 54,002)	30-day readmission (N = 8,104)	p value
Age, years	62.7 (47.3–70.8)	64.1 (52.8–70.8)	<0.001ᵃ
Length of stay, days	4 (2–7)	3 (1–5)	<0.001ᵃ
Total cost, CNY	15,208 (7,373–40,127)	9,634 (5,589–18,203)	<0.001ᵃ
Surgery, n (%)	34,915 (64.6%)	2,293 (28.3%)	<0.001ᵇ
Year of discharge, n (%)	2023: 26,840 (49.7%) 2024: 27,162 (50.3%)	2023: 4,189 (51.7%) 2024: 3,915 (48.3%)	0.001ᵇ

ᵃp values calculated using Mann–Whitney U test.

ᵇp values calculated using chi-square test.

Values are presented as median (IQR) for continuous variables and n (%) for categorical variables.

Total cost is shown in Chinese Yuan (CNY).