Table 2.

Sensitivity analyses

	RR (95% CI)	Number of studies	Heterogeneity Q (P‐value)	Interpretation of results
All studies pooled in meta‐analysis	1.32 (1.07–1.66)	8	194.07 (>0.001)	Results show a 24% (95% CI 6–40%) relative risk reduction associated with handwashing. However, there is an evidence of heterogeneity between the pooled estimates denoted by the high chi‐squared value with a statistically significant P‐value.
Excluding the uncontrolled study (Ryan et al. 2001)	1.19 (1.12–1.26)	7	5.76 (0.45)	After excluding the uncontrolled study, the pooled relative risk reduction associated with handwashing came down to 16% (95% CI 11–21%). There was no evidence of heterogeneity between the remaining seven data points.
Excluding cross‐over trial (Dyer et al. 2000)	1.19 (1.11–1.27)	6	5.51 (0.36)	Dyer et al. (2000) was the only cross‐over trial, all other studies followed a parallel group design. Effect of excluding it showed a relative risk reduction as above. No evidence of heterogeneity.
Excluding poorest studies (Niffenegger (1997) and White et al. 2001)	1.18 (1.11–1.25)	5	3.91 (0.41)	Niffenegger (1997) and White et al. (2001) were excluded to test the pooled effect without the two studies with poorest quality. The resultant relative risk reduction was as above. No evidence of heterogeneity.

RR, relative risk.