During October and November 1982, 1,260 Medicare-eligible senior citizens were interviewed in a survey focusing on health care of the elderly. As part of the survey, an experiment was conducted in each of the three survey sites to determine the effects of an advance telephone call to schedule an appointment for a personal interview. One random half sample in each site was sent a lead letter, followed by a telephone call to schedule a personal interview. The other half sample was sent a lead letter followed by a personal contact, with no intervening telephone call. Telephoning to arrange an appointment for a personal interview resulted in a 20 percent saving in data collection costs with only a 1 percent decrease in response rate
Effects of an advance telephone call in a personal interview survey
Bergsten, J., Weeks, M., & Bryan, F. (1984). Effects of an advance telephone call in a personal interview survey. Public Opinion Quarterly, 48(3), 650-657.