Table 2.

Risk of flare among two-dose vaccine recipients vs unvaccinated individuals, after propensity score weighting

	N	Follow-up time (person-year)	Crude incidence (per person-year, 95% CI)	Adjusted IRR* (95% CI)	P-value
Primary outcome
BNT162b2	35	78.23	0.45 (0.32 to 0.62)	0.86 (0.73 to 1.01)	0.0702
CoronaVac	41	91.02	0.45 (0.33 to 0.61)	0.87 (0.74 to 1.02)	0.0962
None	330	612.63	0.54 (0.48 to 0.60)	Ref	–
Secondary outcome
BNT162b2	33	78.65	0.42 (0.29 to 0.58)	0.96 (0.81 to 1.14)	0.6486
CoronaVac	38	91.58	0.41 (0.30 to 0.56)	1.03 (0.87 to 1.22)	0.7373
None	275	620.26	0.44 (0.39 to 0.50)	Ref	–

*Adjusted variables with standard mean difference >0.1; IRR estimated using non-vaccinated group as reference

IRR, incidence rate ratio.