Hand hygiene compliance in the prevention of hospital-acquired infections: a systematic review

The hands of healthcare workers (HCWs) are known to be a primary source of transmission of hospital-acquired infections (HAIs). Thus, both practising hand hygiene (HH) and adhering to HH guidelines are expected to decrease the risk of transmission. However, there is no consensus on the optimal hand hygiene compliance (HHC) rate for HCWs.To systematically review the published literature to determine an optimal threshold for the HCW HHC rate associated with the lowest HAI incidence rate.This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Online databases were searched using comprehensive search criteria for randomized controlled trials and non-randomized controlled studies, investigating the impact of the HCW HHC rate on HAI incidence rates in patients of all ages within healthcare facilities in high-income countries.Of the 8093 article titles and abstracts screened, 35 articles were included in the review. Most studies reported overall HAIs per 1000 patient-days and device-associated HAIs per 1000 device-days. Most studies reported HHC rates between 60% and 70%. Lower HAI incidence rates seemed to be achieved with HHC rates of approximately 60%. The studies included in this review were not originally designed to assess the impact of HHC on HAI incidence rates, but risk of bias was assessed in accordance with the predetermined exposure and outcome criteria. Eleven (31%) studies were deemed to have low risk of bias.Although HHC is part of the HCW code of conduct, very high HHC rates are difficult to reach. In observational studies, HHC and HAIs had a negative relationship up to approximately 60% HHC. Due to flaws in the study design, causality could not be inferred; only general trends could be discussed. Given the limitations, there is a need for high-quality evidence to support the implementation of specified targets for HHC rates.