Incidence, temporal trend and factors associated with ventilator-associated pneumonia in mainland China: a systematic review and meta-analysis

Table 2 The results of subgroup analyses by characteristics of patient populations

Subgroups	Studies	Sample size	Estimate (%)^a	95% CI (%)	I ² (%)	p value^b
Overall^c	93	71,816	23.8	20.6–27.2	98.9	-
Gender
Male	11	2303	22.4	16.6–28.7	90.5	0.085
Female	11	1577	15.8	11.7–20.5	76.8
Age
<60 years	4	1219	14.0	10.5–17.9	55.6	0.039
≥60 years	6	956	30.8	15.2–49.1	96.7
Comatose
Yes	4	318	55.9	42.5–69.0	79.8	<0.001
No	4	2073	10.2	4.7–17.5	94.6
Diabetes
Yes	4	73	42.7	16.4–71.4	84.6	0.276
No	4	442	26.8	20.8–33.2	52.5
Duration of ventilation
< 7 days	10	3582	6.6	4.7–8.9	77.7	<0.001
7–13 days	2	208	41.3	34.8–48.1	0.0
≥14 days	4	114	81.5	57.9–96.7	81.8
Tracheotomy
Yes	12	663	55.6	38.2–72.4	94.5	0.002
No	5	448	25.0	17.6–33.2	71.8
Re-intubation
Yes	4	209	54.6	43.9–65.2	45.9	<0.001
No	4	1233	15.7	9.9–22.5	82.4

CI confidence interval
^aPooled estimates were calculated by a random-effects model
^bThe Q test for heterogeneity was used to compare the incidence across subgroups
^cStudies that reported the cumulative incidence of ventilator-associated pneumonia

ISSN: 1471-2334