Psychiatrists' caseload volume, length of stay and mental healthcare readmission rates: a three-year population-based study.

This study aimed to compare psychiatrists' in-patient caseload volume with length of stay (LOS) and 30-day readmission rates in Taiwan. We hypothesized that high-volume psychiatrists would be associated with shorter LOS and lower 30-day readmission rates. The sample of 66,959 patients hospitalized for the first time for mental disorders was taken from Taiwan's 2001-2003 National Health Insurance Research Database and categorized into four patient groups according to attending psychiatrists' caseload volume. A total of 21,669 (32.4%) of the patients sampled were readmitted within a 30-day period, with the mean LOS being 24.0 (+/-19.5) days. As caseload volume increased, there was a corresponding increase in the adjusted odds ratio for 30-day readmission rates. The regression analysis reveals adjusted LOS for patients treated by psychiatrists with medium caseload volumes was 1.22 days shorter than that for patients treated by low caseload volume psychiatrists. The adjusted LOS for patients seeing high caseload volume psychiatrists was 2.03 days shorter than for those seeing psychiatrists with low caseload volumes; and for the very-high-volume group, it was 7.59 days shorter. Although the findings confirm our hypothesis regarding LOS, they do not support our hypothesis regarding the relationship between psychiatrists' caseload volume and readmission rates.