TABLE 3.

The combined results of subgroup analysis based on average follow‐up time

Outcome	Average follow‐up time	Included studies	Number	I 2	Statistic effect model	Effect estimate	P‐value
Intraoperative bleeding	Less than 2 years	1	100	0%	MD (fixed, 95% CI)	−4.90 [−5.69, −4.10]	<0.00001
	2 years or more	4	343	92%	MD (random, 95% CI)	−3.11 [−4.25, −1.97]	<0.00001
Operation time	Less than 2 years	1	100	0%	MD (fixed, 95% CI)	−12.00 [−15.27, −8.73]	<0.00001
	2 years or more	6	519	95%	MD (random, 95% CI)	−20.01 [−33.92, −6.09]	<0.00001
HHS	Less than 2 years	1	100	0%	MD (fixed, 95% CI)	16.40 [10.07, 22.73]	<0.00001
	2 years or more	3	219	58%	MD (random, 95% CI)	2.13 [−1.87, 6.14]	0.30
Mortality within 1 year	Less than 2 years	1	100	0%	OR (fixed, 95% CI)	0.79 [0.31, 2.05]	0.63
	2 years or more	4	799	0%	OR (fixed, 95% CI)	1.00 [0.60, 1.65]	0.99
Reoperation	Less than 2 years	2	217	85%	OR (random, 95% CI)	1.61 [0.18, 14.41]	0.67
	2 years or more	4	799	10%	OR (fixed, 95% CI)	2.22 [0.97, 5.09]	0.06
Implant‐related complications	Less than 2 years	1	117	0%	OR (fixed, 95% CI)	9.63 [1.16, 79.70]	0.04
	2 years or more	5	411	16%	OR (fixed, 95% CI)	3.10 [1.31, 7.36]	0.01
Deep venous thrombosis	Less than 2 years	2	217	56%	OR (random, 95% CI)	1.29 [0.23, 7.10]	0.77
	2 years or more	3	290	0%	OR (fixed, 95% CI)	0.69 [0.20, 2.31]	0.54
Superficial infection	Less than 2 years	2	217	68%	OR (random, 95% CI)	1.18 [0.13, 10.84]	0.88
	2 years or more	4	358	0%	OR (fixed, 95% CI)	0.97 [0.29, 3.21]	0.96
Non‐union	Less than 2 years	1	117	0%	OR (fixed, 95% CI)	3.21 [0.13, 80.49]	0.48
	2 years or more	4	324	0%	OR (fixed, 95% CI)	1.08 [0.41, 2.86]	0.88

CI, confidence interval; HHS, Harris hip joint function scale; MD, mean difference; OR, odds ratio