Study ID | Study design | Comparator | Intervention | Difference in response rate (primary end point) | Difference in response rate (secondary end point) |
---|---|---|---|---|---|
Ezell 2013 [37] | Post-hoc analysis method | All partcipants were offered the possibility of receiving incentives ($80) for completion of all program modules and surveys) | 4 retention strategies (re-dials of non-working telephone numbers, mailings to the student’s home, obtaining assistance from school administration and communication through Facebook) were used to reconnect with partcipants who were overdue for the 12-month follow-up surveys | The increase in overall questionnaire response (i.e. retention) rate was 21.6% at 12-month follow-up | No secondary end point reported |
Sellers 2015 [38] | Before and after study | The first 1686 participants received routine strategies (support groups, home visits, transportation to and from study visits, frequent attempts to contact clients to reschedule missed visits) | The subsequent 683 participants received enhanced intensive tracing efforts (broadcast a radio announcement in Chichewa, the local language, hiring a community educator to trace missing participants via motorcycle) | Intensive tracing efforts increased the overall response rate from 80% to 87.8% at 28 weeks after randomisation | No secondary end point reported |