OBJECTIVE: Telephone triage programs are becoming very common at children's hospitals across the nation. One of the proposed benefits of these programs is the more efficient use of health care resources by triaging patients to the appropriate level of health care. The purpose of this study is to examine the appropriateness of referrals to a pediatric emergency department (ED) by the Pediatric Health Information Line (PHIL), a hospital-based telephone triage program, versus all other sources of referrals. METHODS: A blinded Delphi rating system was used to review the physician's sheets of 133 consecutive ED referrals by PHIL for medical appropriateness. A total of 260 randomly selected control patients seen in the ED during the same period were similarly reviewed. If 2 of 3 pediatric emergency medicine physicians agreed that an ED visit was appropriate, then it was considered appropriate. A comparison of the 2 groups' ED appropriateness was made using a contingency table chi(2) test. An odds ratio with confidence limits was also calculated. Demographic data were collected for both groups including age, race, gender, and insurance status. RESULTS: The PHIL group had an appropriateness rate of 80.2%, compared with 60.5% for the control group (chi(2) = 14.6369; odds ratio = 2.65; 95% confidence interval [1.5759,4.5008]). CONCLUSIONS: This demonstrated that for the period studied, PHIL referrals to the ED had a 33% higher rate of appropriateness than controls. This evidence supports telephone triage as an efficient gatekeeper for health care resources.