WHEN YOURE ONLY A PHONE CALL AWAY - A COMPARISON OF THE INFORMATION IN TELEPHONE AND FACE-TO-FACE INTERVIEWS

Telephone interviews offer an economical method of obtaining informati on, but little published experience addresses the use of telephone int erviews for the sometimes lengthy questionnaires composed of scales wi th multiple-category items often required in developmental and behavio ral research. In a study of the outcomes of very low birth weight infa nts, circumstances required that we administer a questionnaire, includ ing seven scales composed of several Likert-type items each, to a subs tantial portion of the study population. Those contacted by telephone (n = 1067) differed from those responding face-to-face (n = 822) in be ing less likely to have a very low birth weight child and more likely to be white and of higher maternal education. The length of the interv iew was only slightly shorter by telephone (60.7 +/- 27.9 vs 66.4 +/- 21.0 minutes, p < .001), but respondent fatigue, as indicated by lower completion rates for scales at the end of the interview (92.5%) compa red with those near the beginning (99.5%) did not differ by mode. Inte rnal consistency of parental response (Cronbach's alpha) was high for most scales and did not differ by mode. Because assignment to mode was not random, other factors may influence our findings. However, high c ompletion rates and comparable consistency of response supports the us e of telephone interviews.