Table 1 Results of phone calls made to cohort members
From: Methods used for successful follow-up in a large scale national cohort study in Thailand
First phone call round - (those no longer registered as students) | No. of cases | ||
|---|---|---|---|
Unable to contact1 | 19,976 | ||
Able to contact | Â | Â | |
   - Details correct | 11011 | ||
   - Details changed | 5002 | ||
Total numbers of contacts attempted | 35,989 | ||
Second phone call round - (non-responders) | Â | Â | |
Unable to contact1 | 17344 | ||
Able to contact | 17728 | ||
Had received q'nnaire | Had returned q'nnaire | Action taken | No. of cases |
Yes | Yes | Thank member | 3067 (17.3%) |
Yes | No | Request cooperation | 8634 (48.7%) |
No | - | Check address for next mail-out round | 4361 (24.6%) |
Unsure (but address correct) | - | Add to next mail-out list | 1666 (9.4%) |
Third phone call round (to those never before contacted) | Â | Â | |
Unable to contact1 | 9154 | ||
Able to contact | Â | Â | |
   - Details correct | 1870 | ||
   - Details changed | 2175 | ||
Total number of contacts attempted | 13199 | ||
Fourth phone call round (to remaining non-responders) | Â | Â | |
Unable to contact1 | 10207 | ||
Able to contact | Â | Â | |
Able to contact | Â | Â | |
   - Details correct | 5040 | ||
   - Details changed | 2602 | ||
Total number of contacts attempted | 17,849 | ||