F59. THE STRUCTURE OF THE PRODROMAL QUESTIONNAIRE-16 (PQ-16): EXPLORATORY AND CONFIRMATORY FACTOR ANALYSES IN A GENERAL NON-HELP-SEEKING POPULATION SAMPLE. (9th April 2019) - Howie, Clare
Abstract: Background: The Prodromal Questionnaire-16 (PQ-16; Ising et al., 2012) is a measure used to screen for attenuated psychotic symptoms that may indicate the presence of the at-risk mental state. The PQ-16 has been validated for use in help-seeking populations and the structure of the measure in this population is categorized by three subscales. These are perceptual abnormalities/hallucinations subscale, the unusual thought content/paranoia subscale, and negative symptoms subscale. The present study aimed to examine the structure of the PQ-16 in a non-help-seeking population through exploratory factor analysis and a confirmatory factor analysis. Methods: Participants (n=722) were recruited through Amazon's Mechanical Turk (MTurk) and completed the PQ-16 as part of a battery of questionnaires. For the exploratory factor analysis, the mean age of the sample was 27.93 years (SD=4.8), 55% of the sample were male, and 49% were single. The exploratory factor analysis, using principal axis factoring and oblique rotation, indicated a two-factor model was suitable for the PQ-16 in this population. Based on the current study and previous studies, three separate confirmatory factor models will be analyzed using SPSS Amos Version 25. Results: The exploratory factor analysis indicated that there was a two-factor model suitable for this sample. Factor 1 appeared to represent perceptual abnormalities/hallucinations, while factor 2 was interpreted as general symptoms. Factor loadings indicated that items 2 & 14 of the PQ-16 did not fit into either factor and were excluded from the two-factor confirmatory factor model. Exploratory factor analysis has been completed, and confirmatory factor analysis of the PQ-16 in a similar non-help-seeking population is underway. Discussion: The exploratory factor analysis indicated that a two-factor model is suitable for this sample (Factor 1 representing perceptual abnormalities/hallucinations; factor 2 representing general symptoms). The confirmatory factor analysis will allow us to explore what model is the best fit for the PQ-16 in this population.