Table 3.

Retention planning: developing a robust participant-tracking system

Study information	Examples of data capture
Participant information	Demographics and study information for mother and child, contact information, assigned field interviewer, status changes (e.g., adoption)
Participant contacts	Mode (text, phone, email), nature (scheduling, reminder, check-in), content (date, time, contact information), frequency, time since last contact
Study status	Referral status (e.g., ineligible/declined/pending), study status (e.g., “need-to-reach”/re-engaged/withdrawn/completed)
Interviews	Type (in-person or telephone, paper or electronic), timing (within deadlines or not), nature (booked, cancelled, completed, partial, missed)
Honoraria	Gift card tracking and reconciliation
Field interviewers	Schedule and availability, participant case load, data quality checks
Communication	Among field interviewers (masked to group allocation) and onsite team
Progress reports	Monitoring recruitment and retention, generating progress reports
Randomization	Secure treatment group allocation
Retention efforts	Tracking engagement and retention materials, consent for future contact
Retention costs	Staffing hours per retention strategy (e.g., average number, frequency and type of contacts, interview mode)