["The objective of this prospective, randomized, controlled study was to evaluate whether confirmation calls made one or two working days before scheduled appointments reduce the percentage of broken appointments in a children's hospital dental clinic.", 'Patients were randomly assigned to three groups: 1) confirmation call made one working day before appointment, 2) confirmation call made two working days before appointment; and 3) control group (no confirmation call). Clinic staff made confirmation calls during normal office hours. Patient arrival was classified as 1) < or =15 minutes late; 2) > 15 minutes late; or 3) broken appointment.', 'Three hundred and thirteen subjects were enrolled in the study: 77 subjects in group 1; 71 subjects in group 2; and 84 subjects in the control group. Eighty-one subjects (26%) could not be contacted by telephone. Overall, there was a 62% reduction in broken appointments among patients who received a confirmation call as compared to the control group. There was no significant difference between confirmation calls placed one or two working days prior to the appointment (P=0.51). Confirmation calls had no effect on punctuality. In comparing indigent care and private insurance, there was no significant difference in broken appointments. However, within the private insurance group, a confirmation call resulted in 93% of patients keeping their appointment as compared to 63% in the control group (P<0.001). No significant difference was noted in the indigent care group, with 79% of patients in the confirmation call group keeping their appointments as compared to 66% in the control group (P=. 093).'] Does the effect of confirmation call on appointment-keeping behavior of patients in a children 's hospital dental clinic?