Document Type


Publication Date



Canadian Journal of Psychiatry





First Page


Last Page


URL with Digital Object Identifier



Objective: There is a dearth of information on people with first-episode psychosis who do not access specialized early psychosis intervention (EPI) services. We sought to estimate the proportion of incident cases of nonaffective psychosis that do not access these services and to examine factors associated with EPI admission. Methods: Using health administrative data, we constructed a retrospective cohort of incident cases of nonaffective psychosis in the catchment area of the Prevention and Early Intervention Program for Psychoses (PEPP) in London, Ontario, between 1997 and 2013. This cohort was linked to primary data from PEPP to identify EPI users. We used multivariate logistic regression to model sociodemographic and service factors associated with EPI admission. Results: Over 50% of suspected cases of nonaffective psychosis did not have contact with EPI services for screening or admission. EPI users were significantly younger, more likely to be male (odds ratio [OR] 1.58; 95% confidence interval [CI] 1.24 to 2.01), and less likely to live in areas of socioeconomic deprivation (OR 0.51; 95% CI 0.36 to 0.73). EPI users also had higher odds of psychiatrist involvement at the index diagnosis (OR 7.35; 95% CI 5.43 to 10.00), had lower odds of receiving the index diagnosis in an outpatient setting (OR 0.50; 95% CI 0.38 to 0.65), and had lower odds of prior alcohol-related (OR 0.42; 95% CI 0.28 to 0.63) and substance-related (OR 0.68; 95% CI 0.50 to 0.93) disorders. Conclusions: We need a greater consideration of patients with first-episode psychosis who are not accessing EPI services. Our findings suggest that this group is sizable, and there may be sociodemographic and clinical disparities in access. Nonpsychiatric health professionals could be targeted with interventions aimed at increasing detection and referral rates.