Infections, accidents and nursing overtime in a neonatal intensive care unit

The paper investigates the effects of nursing overtime on nosocomial infections and medical accidents in a neonatal intensive care unit (NICU). The literature lacks clear evidence on this issue and we conjecture that this may be due to empirical and methodological factors. We model the occurrences of both events using a sample of 3979 neonates who represents over 84,846 observations (infant/days). We exploit an important change in workforce arrangement that was implemented in June 2012, and which aimed at reducing overtime hours to identify a causal impact between the latter and the two outcomes of interest. We contrast the results using a standard mixed-effects logit model with those of a semiparametric mixed-effects logit model. Contrary to the mixed-effects logit model, the semiparametric model unequivocally shows that both adverse events are impacted by nursing overtime as well as being highly sensitive to infant and NICU-related characteristics. Furthermore, the mixed-effects logit model is rejected in favour of the semiparametric one.