Assessment of length of stay in a general surgical unit using a zero-inflated generalized Poisson regression
Roghaye Farhadi Hassankiadeh, Anoshirvan Kazemnejad , Mohammad Gholami Fesharaki, Siamak Kargari, Nasim Vahabi
. Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran. , Kazem_an@modares.ac.ir
Abstract: (1458 Views)
Background: The effective use of limited health care resources is of prime importance. Assessing the length of stay (LOS) is especially important in organizing hospital services and health system. This study was conducted to identify predictors of LOS among patients who were admitted to a general surgical unit.
Methods: In this cross-sectional study, the sample included all patients who were admitted to the general surgical unit of Shariati hospital in 2013 (n= 334). To determine the factors affecting LOS, Zero-inflated Poisson (ZIP), zero-inflated negative binomial (ZINB), and zero-inflated generalized Poisson (ZIGP) regression models were fitted using R software, and then the best model was selected.
Results: Among all 334 patients, the mean (±SD) age of the patients was 45.2 (±16.47) years and 220 (65.9%) of them were male. The results revealed that based on ZIGP model, type of surgery (appendicitis, abdomen and its contents, hemorrhoids, lung, and skin), type of insurance, comorbid diseases (hypertension, heart disease, and hyperlipidemia), place of residence (local and non-local), age, and number of tests had significant effects on the LOS of GS patients.
Conclusion: According to the Akaike information criterion (AIC) in each fitted model, it was found that ZIGP regression model is more appropriate than ZIP and ZINB regression models in assessing LOS in GS patients, especially due to the presence of excess zeros and overdispersion in count data.
Keywords: Length of stay, General surgical unit, Zero-inflated generalized Poisson regression
Full-Text [PDF 427 kb] (466 Downloads)
Type of Study: Original Research | Subject: Biostatistics and Epidemiology
http://mjiri.iums.ac.ir/article-1-4104-en.html
