title: Prolongation of length of stay and Clostridium difficile infection: a review of the methods used to examine length of stay due to healthcare associated infections.
abstract: BACKGROUND
  It is believed that Clostridium difficile infection (CDI) contributes to a prolongation of length of stay (LOS). Recent literature suggests that models previously used to determine LOS due to infection have overestimated LOS, compared to newer statistical models. The purpose of this review is to understand the impact that CDI has on LOS and in doing so, describe the methodological approaches used.
  
  
  OBJECTIVE
  First, to investigate and describe the reported prolongation of LOS in hospitalised patients with CDI. Second, to describe the methodologies used for determining excess LOS.
  
  
  METHODS
  An integrative review method was used. Papers were reviewed and analysed individually and themes were combined using integrative methods.
  
  
  RESULTS
  Findings from all studies suggested that CDI contributes to a longer LOS in hospital. In studies that compared persons with and without CDI, the difference in the LOS between the two groups ranged from 2.8days to 16.1days. Potential limitations with data analysis were identified, given that no study fully addressed the issue of a time-dependent bias when examining the LOS. Recent literature suggests that a multi-state model should be used to manage the issue of time-dependent bias.
  
  
  CONCLUSIONS
  Studies examining LOS attributed to CDI varied considerably in design and data collected. Future studies examining LOS related to CDI and other healthcare associated infections should consider capturing the timing of infection in order to be able to employ a multi-state model for data analysis.
authors.affiliation: School of Nursing, Midwifery and Paramedicine, Australian Catholic University, PO BOX 256, Dickson, ACT, Australia. bgmitc001@myacu.edu.au.
authors.forename: Brett G
authors.initials: BG
authors.lastname: Mitchell
authors.forename: Anne
authors.initials: A
authors.lastname: Gardner