Key points are not available for this paper at this time.
Clyde R. Pope, Samuel S. Yoshioka, Merwyn R. Greenlick, Determinants of Medical Care Utilization: The Use of the Telephone for Reporting Symptoms, Journal of Health and Social Behavior, Vol. 12, No. 2 (Jun., 1971), pp. 155-162
Pope et al. (Tue,) studied this question.