Internal Validation of the Latvian Version of 16-Item Prodromal Questionnaire in A Help-Seeking Adolescent Population: Psychometric Analysis and Associated Factors.

Objectives: The prodromal phase of a psychotic disorder is a period of altered functioning before the onset of the acute state; several interviews have been developed to determine whether individuals present with prodromal symptoms. The 16-item Prodromal Questionnaire (PQ-16) is a screening tool for evaluating those at risk of developing a psychotic disorder. The study aimed to evaluate the psychometric properties of the Latvian version of the PQ-16 in a sample of help-seeking adolescents referred for diagnostic assessment and look for possible associated socio-demographic and health-related factors.

Methods: A cross-sectional study included patients admitted for evaluation between November 2022 and February 2023 in Riga's Children's Clinical University Hospital Child Psychiatry clinic. The data were collected during outpatient consultations by mental health professionals. We used the Latvian translation of PQ-16 and the socio-demographic and health-related factors questionnaire. Data were analysed with IBM SPSS 28; the scale's diagnostic accuracy and internal validity were examined.

Results: The study involved 107 adolescents aged 12% to 17%, 80.5% female, with a mean age of 14.98 (CI 14.70-15.26). Socio-demographic data and health-related variables did not significantly differ between the sexes (p > 0.05). The Latvian PQ-16 demonstrated excellent internal reliability with a Cronbach's alpha of 0.890. All 16 items were found to be valid with p < 0.001. A significant number of participants (73.8%) scored above the current cut-off of ≥ 6 with a mean of 9.17 (95% CI 8.41-9.93). Certain socio-demographic factors, such as female gender (p < 0.001), fair school performance (p = 0.048) and recent changes in school performance (p < 0.001), demonstrated a significant association with higher scores. Additionally, there were found significant associations between positive screening and health-related factors such as obstetric complications (p = 0.044), smoking (p = 0.002), alcohol consumption (p = 0.021), history of bullying in school (p < 0.001) and emotional abuse at home (p = 0.011).

Conclusions: Latvian translation of PQ-16 showed high internal reliability and validity levels. Positive PQ-16 screening was associated with female gender, worsened school performance, obstetric complications, substance abuse and experienced emotional violence. The average score of 9.17 positive answers and 73.8% of participants screening positive for attenuated psychotic symptoms is significantly higher than in recent studies under similar conditions.