Table 2 Inverse probability of censoring-weighted risk of SARS-CoV-2 infection on 50 and 120 days after the first dose administration by protocol, Georgia, United States, December 2020-March 2022

From: Comparative effectiveness of alternative intervals between first and second doses of the mRNA COVID-19 vaccines

Manufacturer

Protocol

50 days after the first dose

120 days after the first dose

Weighted cumulative risk (95% CI), %

Ratio (95% CI)

Weighted cumulative risk (95% CI), %

Ratio (95% CI)

Pfizer-BioNTech

Recommended

0.94 (0.92–0.95)

Ref.

2.17 (2.15–2.19)

Ref.

Pfizer-BioNTech

Late-but-allowable

1.01 (0.99–1.02)

1.08 (1.06–1.10)

1.72 (1.69–1.74)

0.79 (0.78–0.81)

Pfizer-BioNTech

Late

1.07 (1.05–1.08)

1.14 (1.12–1.17)

2.22 (2.18–2.25)

1.02 (1.01–1.04)

Moderna

Recommended

0.62 (0.61–0.64)

Ref.

1.18 (1.16–1.20)

Ref.

Moderna

Late-but-allowable

0.72 (0.71–0.74)

1.16 (1.14–1.18)

1.05 (1.02–1.07)

0.89 (0.87–0.91)

Moderna

Late

0.73 (0.71–0.74)

1.16 (1.14–1.19)

1.44 (1.40–1.47)

1.22 (1.19–1.25)

  1. CI confidence interval, Ref reference.
  2. Intervals between the 1st and 2nd doses: the “recommended” interval is 17–25 days for Pfizer-BioNTech and 24–32 days for Moderna; the “late-but-allowable” interval is 26–42 days for Pfizer-BioNTech and 33-49 days for Moderna; the “late” interval is ≥43 days for Pfizer-BioNTech and ≥50 days for Moderna. 95% CIs were calculated using a nonparametric bootstrap based on 200 resamples. The estimated cumulative risk and 95% CI on Day t after the first dose (t = 1, 2, …, 180) can be found in the Supplement (csv file).
Back to article page