. 2022 Jan 24;11:16. doi: 10.1186/s13756-021-01049-9

Table 2.

Characteristics of studies investigating the influence of alcohol-based handrub application time

Author Date Country	Design	Setting	Participants	Tested ABHR application times	Outcome measure(s)	Data collection method	Standardisation	Results
Dharan et al (2003) [30] Switzerland	Within-subject NRT	Laboratory	12 volunteers	15 s 30 s	Bacterial load on hands	Fingertips	Product 4 ABHR—1. 80% ethanol (w/v) rinse; 2. 95% ethanol (w/v) rinse; 3. 75% isopropanol (v/v) & 0.5% chlorhexidine rinse 4. 60% isopropanol gel Reference 2-propanol 60% (v/v) ABHR volume 3 ml Application technique ABHR was applied to the cupped fingertips of the right hand, which were disinfected by rubbing of the thumb against fingertips and fingernails Artificial contamination (S. aureus, Pseudomonas aeruginosa, Enterococcus faecalis)	Mean log₁₀ RF at 30 s significantly higher than 15 s for all ABHR products (P < 0.01)
Rotter et al (2009) [25] Austria	Within-subject RCT	Laboratory	15 volunteers	15 s 30 s 60 s	Bacterial load on hands	Fingertips	Product liquid ABHR 2-propanol 60% (v/v) ABHR volume 3 ml Application technique 6-steps Artificial contamination (E. coli)	Mean log RF (SD) 15 s: 3.5 (0.8) 30 s: 3.7 (0.8) 60 s: 4.5 (0.8) Significant between 30 s & 60 s (P < 0.01); and between 15 s & 60 s (P < 0.001)
Kramer et al (2017) [16] Germany	RCT	Clinical	14 nurses	15 s 30 s	Bacterial load on hands	Fingertips	Product ABHR 45% (w/w) propan-2-ol + 30% (w/w) propan-1-ol + 0.2% mecetroniumetile sulfate Average ABHR volume used 3.4 ml Application technique 6-steps	Mean log RF (SD) 15 s: 1.24 (0.68) 30 s: 1.31 (0.61) (P = 0.59)
Pires et al (2017) [24] Switzerland	Within-subject RCT	Laboratory	1) 23 HCWs 2) 18 HCWs	1) 10 s 15 s 20 s 30 s 45 s 60 s 2) 15 s 30 s	Bacterial load on hands	Fingertips	Product ABHR isopropanol 60% (v/v) ABHR volume 3ml Application technique 6-steps Artificial contamination (E. coli)	Mean log₁₀ reduction after 15 s non-inferior to 30 s; 0.11 log₁₀ lower (95% CI, − 0.46–0.24) All durations resulted in a reduction in bacterial count (P < 0.001) Reductions after 10, 15 or 20 s not different to 30 s (P = 0.174, 0.312, 0.720) Reductions after 30 s higher than 45 or 60 s (P = 0.004, 0.011)
Pires et al (2019) [23] Switzerland	Within-subject RCT	Laboratory	18 HCWs	15 s 30 s	Bacterial load on hands	Fingertips	Product ABHR isopropanol 60% (v/v) ABHR volume customized to hand size Small hands: 2.2 ml (IQR 2.2–2.4); Medium hands: 2.3 ml (IQR 2.2–2.3); Large hands: 3.2 ml (IQR 3.0–3.4) Application technique variations 6-steps according to daily routine Artificial contamination (E. coli & S. aureus)	Log₁₀ RF 15 s non-inferior to 30 s -0.06 log₁₀ (95% CI, − 0.34–0.22; P = 0.659)
Harnoss et al (2020) [18] Germany	Crossover RCT	Clinical	14 nurses	15 s 30 s	Bacterial load on hands	Fingertips	Product liquid ABHR 45% (w/w) propan-2-ol + 30% (w/w) propan-1-ol + 0.2% mecetroniumetile ABHR volume 4 ml Application technique 6-steps	Mean log₁₀ RF (SD) 15 s: 0.92 (0.47) 30 s: 0.89 (0.45) (P = 0.638)

ABHR – alcohol-based handrub; CI – confidence intervals; E. coli – Escherichia coli; HCW – healthcare workers; S. aureus – Staphylococcus aureus; IQR – interquartile range; NRT – non-randomised trial; RCT – randomised controlled trial; RF – reduction factor; SD – standard deviation