Background Psychotic-like experiences (PLEs) are common in clinical adolescent samples and form a continuum based on their frequency and intensity. PLEs can have harmful effects on both behaviour and affect. Methods Prevalence and subjective distress due to PLEs were assessed with the Prodromal Questionnaire-Brief (PQ-B) and depressive symptoms with the Beck Depression Inventory (BDI-21A) among adolescents (N = 399; 71.7% female, mean age 14.9 years, range 13–18) entering specialized adolescent psychiatric services. Various PQ-B Distress scale cut-off points were tested for their ability to detect high and low BDI scores using the superiority index, the effect size for mean difference, and spline regressions. Results The mean number of endorsed PLEs assessed with the PQ-B was 3.27 (SD 3.64; males: M 1.75; SD 2.78; females: M 3.89; SD 3.78), while mean PQ-B Distress scores were 20.33 (SD 18.03; males: M 11.84; SD 13.90; females: M 23.74; SD 18.40). The most common PLE within both genders were experiences of paranoia and suspiciousness, with a prevalence of 59.9%. BDI scores and PQ-B distress scores were strongly associated (r = 0.534, p<.001). Superiority indices, effect sizes, and spline regressions indicated that a low PQ-B Distress cut-off of 2 or 3 was most informative both when using BDI as a continuous variable and when dichotomized as mild depression (≥10) or major depressive disorder (≥16). Conclusion PLEs are common among adolescent entering psychiatric care. Even a relatively small amount of distress due to PLEs indicates clinical levels of depressive symptoms.
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