Table 1.
Characteristics at Start of Follow-up of the Participants in the Norwegian Mother, Father, and Child Cohort Study (MoBa) and Senior Cohort Included in Vaccine Effectiveness Analyses, N = 85 801
| Characteristic | Value |
| MoBa | 81 290 (94.7) |
| Senior cohort | 4511 (5.3) |
| Sex, women | 52 638 (61.3) |
| Returned all questionnaires, yesa | 48 379 (56.4) |
| Age groups, y | |
| <40 | 2082 (2.4) |
| 40–49 | 41 867 (48.8) |
| 50–59 | 34 999 (40.8) |
| 60–69 | 3639 (4.2) |
| ≥70 | 3214 (3.7) |
| Previous COVID-19 infection, yesb | 3928 (4.6) |
| COVID-19 vaccination status at start of follow-upc | |
| Dose 1 | |
| Date dose 1, median | 17 June 2021 |
| Interval in days between dose 1 and 2, median | 47 |
| Comirnaty | 68 750 (80.1) |
| Spikevax | 11 666 (13.6) |
| Vaxzevria or other | 5385 (6.3) |
| Dose 2 | |
| Comirnaty | 62 068 (72.3) |
| Spikevax | 23 715 (27.6) |
| Vaxzevria or other | 18 (0.02) |
| Booster dose | |
| Comirnaty | 39 251 (45.7) |
| Spikevax | 23 253 (27.1) |
| No booster dose before start of follow-up | 23 297 (27.2) |
Data are No. (%) except where indicated.
a
Participants in MoBa received 5 questionnaires and participants in the senior cohort received 4 questionnaires.
b
Defined as an infection registered in the Norwegian Surveillance System for Communicable Disease with date more than 14 days prior to the participant's start of follow-up.
c
All 85 801 participants included in the analyses had received at least 2 vaccine doses at start of follow-up.