Creation and validation of the Postpartum Specific Anxiety Scale Research Short-Form (PSAS-RSF)

The Postpartum Specific Anxiety Scale (PSAS) is a valid, reliable measure of postpartum anxiety (PPA). However, it contains 51 items, so is limited by its length. This study aimed to reduce the number of items in the PSAS, produce a small number of high-performing short-form tools, and confirm the factor structure of the most statistically and theoretically meaningful model. A pooled sample of English-speaking mothers (N = 2033) with infants up to 12 months were randomly split into three samples. (1) A principal component analysis (PCA) was conducted to initially reduce the items (n = 672). (2) Four short-form versions of varying length (informed by statistical, theoretical, lay-person, and expert-guided feedback) were developed and their factor structure examined (n = 673). (3) A final confirmatory factor analysis (CFA) was performed to confirm the factor structure of the PSAS Research Short-Form (PSAS-RSF) (n = 688). PCA and theoretical review reduced the items from 51 to 34 (version 1). Statistical review retained 22 items (version 2). Quantitative expert panel data retained 17 items (version 3). Qualitative expert panel data retained 16 items (version 4). The 16-item version was deemed the most theoretically and psychometrically robust. The resulting 16-item PSAS-RSF demonstrated good psychometric properties and reliability. The PSAS-RSF is the first brief research tool which has been validated to measure PPA. Our findings demonstrate it is theoretically meaningful, statistically robust, reliable, and valid. This study extends the use of the measure up to 12 months postpartum, offering broader opportunity for measurement while further enhancing accessibility through brevity.