Objectives: Determine if 1) proximity of referral to a federally qualified health center (FQHC) improves initial follow-up rates for discharged emergency patients, 2) improved initial follow-up rates are associated with improved rates for an ''ongoing relationship'' with the FQHC, and 3) an ongoing relationship with an FQHC is associated with decreased subsequent emergency department (ED) utilization over a 2-year follow-up period.Methods: An expedited referral system was initiated just prior to January 2004 for discharged ED patients referred to an FQHC. Referral categories were as follows: R1 = next-day; R2 = 2 to 7 days; R3 = 2 to 3 weeks; and R4 = follow-up as needed. The FQHC database for 2004-2006 was merged with the ED database from 2004 through 2006. The FQHC database contained all ED referrals, the referral category, whether the patient kept his or her initial ED referral appointment, all subsequent scheduled clinic appointments, and whether the patient kept any of the subsequent scheduled appointments. We compared initial referral follow-up rates and subsequent scheduled visits to the FQHC for each referral category, over a 2-year follow-up period. We evaluated the effects of age, sex, marital status, insurance status, initial triage score, race, comorbidities, and number of prescription medications on initial follow-up, and subsequent kept appointments with the FQHC. We defined an ''ongoing relationship'' as one or more kept scheduled appointments annually. Finally, we compared the number of subsequent ED visits over the follow-up period between patients who maintained an ongoing relationship with the FQHC and those who did not, before and after correcting for the demographic and clinical factors.Results: There were 520 referrals over the study period. Follow-up rates ranged from 37.5% (95% confidence interval [CI] = 13.5% to 69.6%) for R1 to 9.0% (95% CI = 4.4% to 17.0%) for R4. The overall ongoing relationship rate was 7.1% (95% CI = 5.2% to 9.7%) and had weak association with temporal proximity of referral. On bivariate analysis, older age, female sex, white race, one or more comorbidities, and three or more medications were associated with increased rates of initial follow-up. These factors (with the exception of race) were also associated with increased rates of developing an ongoing relationship. Patients with an ongoing relationship with the FQHC had more repeat ED visits over the study period than did patients without (3.6 vs. 1.7, p = 0.003). However, this difference was no longer evident after adjusting for age, race, comorbidities, and medication usage.Conclusions: Overall patient follow-up to an FQHC was low, but increased with next-day or same-week referral. The ongoing relationship rate was low, but increased with temporal proximity of ED referral. Increased comorbidities and medication usage were significantly associated with increased initial followup rates, development of an ongoing relationship, and subsequent ED utilization. Patients with an ongoing relationship with the FQH...