Primary and secondary outcomes
AIDS, infected with HIV during the trial
AIDS, SECONDARY
The primary outcome was 18-month retention in PMTCT care, measured by whether the mother or infant attended follow-up care between 16 and 24 months after delivery. Follow-up care included clinic appointments, maternal viral load tests, and infant HIV tests. Information about HIV laboratory tests and clinical visits was collected from patient files and registers (antenatal care and HIV-exposed infant registers) at the study sites as well as from the National AIDS and STI Control Programme (NASCOP) (Kenya) database. Visit dates and clinical data were recorded on study-specific forms when the participants were expected to have completed follow-up. NASCOP data were abstracted at the end of follow-up, and data management was completed in September 2020.Secondary outcomes included: mother or infant retention in PMTCT care between 6 and 12 months postpartum (attending follow-up care 4–14 months after delivery); linkage to chronic HIV care (attending follow-up care 24–30 months after delivery or confirmation that the participant was linked to chronic care); time in care up to 30 months (those who did not have clinical follow-up 24–30 months from enrolment and were not linked to chronic HIV care were considered to have dropped out of care); and facility or home birth. We also assessed the number of infants who were infected with HIV during the trial. Women enrolled in PMTCT care again between 24 and 30 months postpartum (due to a new pregnancy) and women with adverse birth outcomes linked to chronic care before the 24–30 months timeframe were included as being linked to chronic HIV care.The effect of the intervention on early infant testing of HIV has been reportedBefore completion of trial, the primary outcome was adjusted to reflect Kenya’s implementation of Option B+, emphasizing mothers’ continuation of ART for life, by expanding the definition of retention from an infant returning for HIV testing at 18–24 months to include evidence of a clinical visit for a mother, or her infant, within 16–24 months postpartum. This allowed women who were still being transferred into chronic HIV care at 18 months postpartum to be considered retained. In addition, we added linkage to chronic HIV care up to 30 months as a secondary outcome to enable a more thorough investigation of long-term retention in PMTCT care. These changes were documented in the ISRCTN registry before any outcome analyses occurred (