Table 1.

Description of included studies

Author	Study period	Country	sample	Category	Urgency	quality	P(95% CI
Bhangu et al.	Jan 1 to March 31, 2020	UK	1128	Any	Any	Low risk	24 [21,26]
Cai et al. [53]	February, 2020	China	7	Any	Any	Low risk	43 [10,82]
Casanova et al. [28]	March 11 to May 15, 2020	Portugal	148	Cardiac	Emergency	Low risk	1 [0,5]
Cheung et al. [75]	March 1 to May 22, 2020	USA	10	Orthopedics	Emergency	Low risk	10 [0,45]
Doglietto et al. [76]	Feb 1, April 23	Italy	41	Any	Any	Low risk	20 [9,35]
Dursun et al. [30]	March 10 to May 20, 2020	Turkey	200	Gynecology	Elective	Low risk	12 [8,17]
Egol et al. [36]	Feb 1 to April 15, 2020	USA	253	Orthopedics	Elective	Low risk	7 [4.11]
Kayani et al. [44]	Feb 1 to April, 2020	UK	82	Orthopedics	Elective	Low risk	30 [21,42]
LeBrun et al. [54]	March 20 to April 24, 2020	USA	9	Orthopedics	Any	Low risk	78 [40,97]
Lei et al. [77]	Jan 1 to Feb 5, 2020	China	34	Any	Any	Low risk	21 [9,38]
Li et al. [78]	Jan 1 to Feb 5, 2020	China	54	Any	Emergency	Low risk	15 [7,27]
Macey et al. [65]	Dec to March 2020	UK	76	Orthopedics	Any	Low risk	28 [18,39]
Martino et al. [79]	Feb 17 to March 31, 2020	Spain	15	Any	Any	Low risk	20 [4,48]
Mi et al. [80]	Jan 1 to Feb 27,2020	China	3	Orthopedics	Any	Low risk	20 [4,48]
Pai et al. [32]	March 24 to May 31, 2020	India	184	Any	Elective	Low risk	20 [14,26]
Peng et al. [55]	January 2020	China	11	Thoracic	Any	Low risk	27 [6,61]
Rajasekaran et al. [27]	March 12 to May 12, 2020	UK	56	Orthopedics	Any	Low risk	4 [0,12]
Santiago et al. [81]	March to May, 2020	Spain	126	Gynecology	Elective	Low risk	12 [7,19]
Seeliger et al. [27]	March 1 to May 23, 2020	France	13	Any	Emergency	Low risk	92 [64,100]
Sobti et al. [51]	March 1 to May 31, 2020	UK	206	Orthopedics	Any	Low risk	4 [2,8]
Stevenson et al. [82]	March 4 to May 22, 2020	UK	100	Orthopedics	Elective	Low risk	7 [3,14]
Stoneham et al. [57]	March 1 to June 12,020	UK	48	Orthopedics	Elective	Low risk	–
Zhang et al. [52]	Jan 1 to March 20, 2020	China	133	Obstetrics	Both	Low risk	–