4. Results from studies reporting microbiological data.

Study	Design/ Intervention	Results
Intervention: Multimodal, not WHO
Ho 2012	RCT	· Reduced respiratory outbreaks: IRR 0.12, 95% CI 0.01 to 0.93 · Reduced MRSA infections requiring hospitalisation: IRR 0.61, 95% CI 0.38 to 0.97
Lee 2013	ITS	No reduction related to the hand hygiene promotion campaign alone in: · MRSA in clinical isolates: IRR 1.44, 95% CI 0.96 to 2.15 · MRSA infections: IRR 1.28, 95% CI 0.79 to 2.06
Yeung 2011	RCT	Reduced serious infections (cases per 1000 resident‐days): · Intervention group: pre: 1.42; post: 0.65 (difference: ‐0.77) · Control groups: pre: 0.49; post: 1.05 (difference: 0.56) Reduced pneumonia (cases per 1000 resident‐days) · Intervention group: pre: 0.91; post: 0.28 (difference: ‐0.63) · Control group: no change Reduced deaths per 1000 resident‐days: · Intervention group: pre: 0.37; post: 0.10 (difference: ‐0.27) · Control group: no change
Intervention: Multimodal, WHO based
Derde 2014	ITS	· Trend in MRSA acquisition following hand hygiene campaign: IRR 0.976, 95% CI 0.954 to 0.999; · No changes in acquisition of VRE or HRE
Mertz 2010	RCT	No difference in MRSA colonisation (cases per 1000 patient‐days): · Intervention group: 0.30 · Control group: 0.31
Perlin 2013	ITS	MRSA CLABSI per 1000 line days: · Pre: .497 (difference: ‐0.191) · Post: .306 MRSA VAP per 1000 ventilator days: · Pre: 1.088 (difference: ‐0.538) · Post: 0.550
Vernaz 2008	ITS	· MRSA decreased by 0.03 clinical isolates per 100 patient‐days for each litre of ABHR per 100 patient‐days · No change in C. difficile
Intervention: Multimodal, WHO‐enhanced
Vernaz 2008	ITS	· No change in MRSA clinical isolates · No change in C. difficile
Intervention: Performance feedback
Stewardson 2016	RCT	Primary bloodstream infection · Enhanced feedback: IRR 0.71, 95% CI 0.54 to 0.95 · Enhanced feedback + patient participation: IRR 1.02, 95% CI 0.78 to 1.34 · Control: IRR 0.57, 95% CI 0.40 to 0.80 Period prevalence of HCAIs · Enhanced feedback: IRR 0.91, 95% CI 0.68 to 1.23 · Enhanced feedback + patient participation: IRR 1.05, 95% CI 0.78 to 1.40 · Control: IRR 1.33, 95% CI 0.94 to 1.88 Colonisation with MRSA · Enhanced feedback: IRR 0.79, 95% CI 0.66 to 0.95 · Enhanced feedback + patient participation: IRR 0.82, 95% CI 0.67 to 0.99 · Control: IRR 0.92, 95% CI 0.77 to 1.13

AHBR: alcohol‐based hand rub; C. difficile: Clostridium difficile; CLABSI: central line‐associated blood stream infections; CI: confidence interval; HCAI: healthcare‐associated infection; HRE: highly‐resistant Enterobacteriaceae; IRR: incidence rate ratio; ITS: interrupted time series; MSRA: methicillin‐resistant Staphylococcus aureus; RCT: randomised (controlled) trial; VAP: ventilator‐associated pneumonia; VRE: vancomycin‐resistant enterococci; WHO: World Health Organization