Table 4.

Sensitivity analysis for primary outcomes comparing percutaneous dilatational and surgical tracheostomy in critically ill patients

Outcome	Subgroup	No. of studies	Estimate of OR	95% CI	Test for between subgroup heterogeneity
Infection	Allocation concealment				P = 0.65
	Yes	4	0.33	0.14–0.77
	No	7	0.24	0.11–0.53
	Method of PDT				P = 0.62
	Multiple dilator	9	0.24	0.13–0.47
	Forceps	1	0.15	0.01–3.74
	Translaryngeal	1	0.55	0.15–2.1
	ST performed				P = 0.70
	ICU	2	0.49	0.12–1.99
	OT	9	0.25	0.13–0.47
	Use of Bronchoscope for PDT				P = 0.28
	Yes	5	0.40	0.18–0.89
	No	6	0.20	0.09–0.46
Bleeding	Allocation concealment				P = 0.67
	Yes	5	0.85	0.46–1.41
	No	5	0.71	0.26–1.94
	Method of PDT				P = 0.33
	Multiple dilator	7	0.96	0.51–1.83
	Forceps	1	1.7	0.15–20.17
	Translaryngeal	1	0.08	0.004–1.37
	Single dilator	1	1.5	0.06–39.24
	ST performed				P = 0.009
	ICU	4	2.01	0.86–4.69
	OT	6	0.29	0.12–0.75
	Use of bronchoscope for PDT				P = 0.08
	Yes	5	1.36	0.65–2.84
	No	5	0.34	0.12–0.92
Mortality	Allocation concealment				P = 0.86
	Yes	5	0.81	0.54–1.22
	No	7	0.77	0.50–1.19
	Method of PDT				P = 0.94
	Multiple dilator	9	0.80	0.57–1.11
	Forceps	2	0.63	0.16–2.45
	Translaryngeal	1	0.84	0.40–1.79
	ST performed				P = 0.2
	ICU	3	1.09	0.61–1.97
	OT	9	0.79	0.50–1.00
	Use of bronchoscope for PDT				P = 0.52
	Yes	6	0.86	0.58–1.28
	No	6	0.71	0.45–1.12

ICU, intensive care unit; OT, operating theatre; PDT, percutaneous dilatational tracheostomy; ST, surgical tracheostomy.