Thirty-one studies were included in the review (n unknown): two were randomised trials, four were cohort studies with a control group, three were cohort studies with no control group, four were before-and-after studies with a control group, and 18 were before-and-after studies without control groups. Eleven studies had a quality score of 1, 10 studies scored 2, nine studies scored 3, and one scored 4. The most frequent flaws were: failure to identify the presence of confounding factors (eight studies); inadequate statistical analysis (six studies); and inadequate sample size (five studies).
Multimodal hand hygiene initiatives (seven studies): Two studies reported a significant reduction in health care-associated infections rates and two studies did not report a significant reduction in these rates. Two studies reported a significant reduction in methicillin-resistant Staphylococcus aureus (MRSA) rates. One study found a reduction in rotavirus rate.
Hand hygiene products (11 studies): A decrease in infection rates following the introduction of a hand sanitiser was reported in three studies, but two studies found no significant reduction in health care-associated infections rates between handwashing and the introduction of a hand sanitiser. Other studies reported a decrease or a significant reduction in: MRSA with or without reductions in vancomycin resistant Enterococcus (three studies); and infection rates in both active intervention groups (one study). One study reported no a significant difference between two active interventions.
Infection control practices (eight studies): A reduction in health care-associated infections rates were reported in two studies, but it was not possible to assess the role of hand hygiene in these studies. Other studies reported a decrease or a significant reduction in: bloodstream infections (one study); bacteraemia (one study); MRSA (two studies); vancomycin resistant Enterococcus (one study); and Clostridium difficile (one study).
Infection control policies (two studies): Significant reductions were noted for Clostridium difficile and health care-associated infections (one study), and the risk of hospital-associated gastrointestinal infections (one study).
Other interventions (three studies): Three studies assessed organisational interventions (administration intervention, electronic monitoring and a survey of current practices), but none reported significant reductions in infections.