Duration of untreated prodromal psychosis among individuals with clinical high risk for psychosis

•The average duration of untreated prodromal symptoms (DUPrS) was 7.1 months, showing similarity between clinical high-risk converters and non-converters. However, the associations with symptom profiles displayed notable differences.•Applying quantile regression, we uncover nuanced associations of DUPrS with clinical variables, emphasizing its role across varying quantiles.•Our study underscores DUPrS's role as an intermediary factor in psychosis, influencing outcomes in clinical high-risk cases. The impact of the duration of untreated psychosis on the outcomes of schizophrenia has been extensively studied. However, there is a notable gap in the current understanding of the relationship between the duration of untreated prodromal symptoms (DUPrS) and the development of psychosis in individuals at clinical high risk (CHR). A sample of 704 individuals with CHR was identified through a structured interview, of who 145 (20.6 %) converted to psychosis (CHR-C) during the 3-year follow-up. The DUPrS was defined as the period between the onset of the first attenuated psychotic positive symptom and the commencement of professional assistance at mental health services. Quantile regression was applied for quantile levels between 0.1 and 0.9, and adjusted for age, sex, and education.The overall sample had a mean DUPrS of 7.1 months. No significant differences were observed in the DUPrS between the CHR-C and non-converter (CHR-NC) groups. Quantile regression analysis highlighted variations in the effects of the DUPrS on clinical variables across the different quantiles. We observed a positive association between DUPrS rank and positive symptoms below the 0.3 quantile, while a positive association between DUPrS rank and negative symptoms above the 0.3 quantile (except 0.7 and 0.9 quantile). A longer DUPrS (> 3 months) was associated with younger age (odds ratio [OR] = 0.948, p = 0.003), a higher proportion of women (OR = 1.474, p = 0.003), higher baseline global function (OR = 1.044, p = 0.003), lower previous global function (OR = 0.921, p