Although missed appointments in service delivery systems reduce effective case management, clini- cal efficiency, staff morale, and resource utilization, researchers have paid little attention to the impact of missed appointments on patient care. This column presents findings from a study that examined predictors of missed appointments during the course of therapy among 2,903 psychiatric patients between the ages of three and 17. Self-report- ed history of maternal depression proved to be the most powerful predictor. Living more than 30 miles from the clinic and having a parent who was single or never married also predicted missed ap- pointments. (Psychiatric Services 61:657-659, 2010) sufficient notification. Estimates put the missed appointment rate in the range of 30% to 50% for most adult psychiatric clinics (2-5), although lit- tle is known about what factors ac- count for variations in rates across agencies. Given the severe shortage of mental health services nationwide, this substantial loss of clinical capacity has far-reaching implications. Aside from the sheer waste of practitioner and staff time, the failure to adhere to treatment, including appointment nonattendance, can result in a variety of negative patient outcomes. These include higher rates of rehospitaliza- tion and psychiatric deterioration. The few studies on missed appoint- ments in child psychiatric outpatient clinics are limited primarily to initial appointments, rather than to those over the entire course of treatment. These few studies also present highly contradictory findings. For example, although results of some studies sug- gest no age effects, results of others have indicated that older children are more likely to miss initial appoint- ments. Data on sex differences are similarly inconclusive. Some report that females are more likely to miss initial appointments, whereas others dispute that finding. Similar discrep- ancies hold for the factors of race and ethnicity. Missed initial appointments have also been found to be signifi- cantly associated with marital status and with parental opposition to being referred for treatment. Therefore, parent factors likely play an important role in appointment attendance. Because of the somewhat limited body of literature and the inconclu- sive findings regarding a topic as im- portant as missed appointments, we used our computerized clinic man- agement system to analyze a wide va- riety of potential predictors in a large and diverse sample of child patients. For our analysis, we selected factors that have been identified as potential- ly predictive of missed appointments in previous studies. However, we also included variables that have not been considered in prior child psychiatric research, such as the type of treat- ment provided and the distance the family has to travel to the clinic. We sought to add to the previous litera- ture by focusing on missed appoint- ments over the course of treatment. Analysis of missed appointments This column presents data from 2,903