Telephone follow-up in a randomized controlled trial in a less developed country: feasibility, validity and...

Telephone follow-up would offer considerable advantages over other modes of follow-up in less developed countries, if it were feasible and the findings were valid and generalizable. Telephone follow-up was assessed in the context of a randomized controlled trial of chest radiography in South African children. Hospital-based clinical outcomes were measured from hospital records, and also by telephone, in a subset of the same patients who offered a contact telephone number. Of 398 subjects offering a telephone number 308 (77.4%) were followed to recovery or for 28 days. Kappa statistics for a subsequent hospital visit, hospital admission, and chest radiograph were 0.88, 0.83, and 0.56, respectively. The effect of chest radiography did not differ significantly in participants accessible and not accessible by telephone. Telephone follow-up was feasible and produced valid and generalizable results at low cost.