Table 1.
Visit and Sample Schedule
| Visit | 1 | 2 | 3 | 4 | 5 | 6 | 7 | Trial Completiona |
|---|---|---|---|---|---|---|---|---|
| Days post-vaccination | 0 | 7 | 28 | 180 | 365 | 545 | 730 | 730 post–trial starta |
| Permissible time window, in days | … | +7/-1 | ±4 | ±28 | ±56 | ±56 | ±90 | ±90 |
| Screening | X | … | … | … | … | … | … | … |
| Consent | X | … | … | … | … | … | … | … |
| Randomization | X | … | … | … | … | … | … | … |
| Vaccination | X | … | … | … | … | … | … | … |
| Medical history and exam | X | … | … | … | … | … | … | … |
| Blood collectionb | Xc | … | X | … | … | X | … | X |
| Blood volume | ~3–5 ml | … | ~3–5 ml | … | … | ~3–5 ml | … | ~3–5 ml |
| AEFI follow-upd | … | X | … | … | … | … | … | … |
| Census update and follow-up contacte | … | … | … | X | X | X | X | … |
| Unblinding and documentation of vaccination | … | … | … | … | … | … | … | X |
Abbreviation: AEFI, adverse event following immunisation.
aAll participants will be unblinded at the same time, at ~730 days after the first participant is enrolled, regardless of when an individual joined the study. Participants who were enrolled during a census update will only complete those visits occurring between their enrollment and the subsequent completion of the trial.
bThe blood collection will be in a subset of 1000 Vi-typhoid conjugate vaccine and 500 control participants. The total volume will be ~12–20 ml per participant.
cThe blood draw on Day 0 will occur before vaccination.
dAt Day 7, a subset of participants will be contacted to collect all AEFIs.
eFollow-up contact includes: compiling a census update and ensuring the participant and family still live in the area and are happy to continue with the study; recording mortality and morbidity in participants, including serious adverse events; and providing a reminder to attend the trial health-care facility if the participant develops a fever of ≥2 days.