TABLE 1.

Basic characteristics of the included studies

Num	Study, year	N (obesity)	Age (year)	Country	Vaccine	Assessment after administration	History of COVID‐19 infection, n	Outcome
1 27	Alexis, 2021	1060 (492)	41.42 ± 12.95	Italy	BNT162b2	The first dose, the second dose	Yes, n = 240	①IgG neutralizing antibodies against the Trimeric complex ②The difference from the baseline titer
2 26	Raul, 2021	248 (22)	23–69	Italy	BNT162b2	The second dose	No	①IgG antibodies against S1/S2 antigens of SARS‐CoV‐2 ②The difference from the baseline titer
3 28	Awadhesh, 2021	552 (67)	44.8 ± 13.1	India	ChAdOx1 nCoV‐19	The first dose, the second dose	Yes, n = 60	①SARS‐CoV‐2 spike antibody titers ②Seroprevalence of antibodies
4 25	Shohei Yamamoto, 2022	2435 (66)	/	Japan	BNT162b2	The second dose	Yes, n = 13	①Anti‐SARS‐CoV‐2 spike IgG titers
5 35	Jer‐Hwa Chang, 2022	270 (59)	23–68	China	ChAdOx1 nCoV‐19	The first dose, the second dose	No	①anti‐RBD and anti‐spike IgG levels
6 34	Andrea Lombardi, 2021	1218 (187)	/	Italy	BNT162b2	Second dose	Undetermined	①Seroprevalence of antibodies >7500 U/ml
7 33	Engy Mohamed El‐Ghitany, 2022	143 (117)	43 ± 11.1	Egypt	AZD1222/BBIBP‐CorV/others	Second dose	Yes, n = 143	①Seroprevalence of anti‐S of SARS‐CoV‐2
8 32	Rami Alqassieh, 2021	288 (249)	/	Jordan	Pfizer‐BioNTech/Sinopharm	Second dose	Yes, n = 8	①Seroprevalence of antibodies
9 31	Xiaoguang Li, 2021	127 (44)	22–73	China	Inactivated vaccines/vector	Second dose	No	①Seroprevalence of neutralizing antibodies
10 30	Hui Zhang, 2022	1156 (356)	18–60	China	Inactivated vaccine	Second dose	No	①Seroprevalence of neutralizing antibodies
11 29	İlker İnanc Balkan, 2022	169 (86)	22–66	China	CoronaVac (Sinovac)	Second dose	Yes, n = 37	①Seroprevalence of antibodies