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Counting every cycle: Validating a measure of period product insecurity in the United States
1Sanford School of Public Policy, Duke University, Durham, NC, USA.
Background:
Period product insecurity (PPI), a material hardship characterized by the repeated inability to afford menstrual products, is rarely integrated into mainstream poverty research in part because we lack measures to capture its incidence.
Objectives:
This article introduces and validates a new measurement instrument, the Van Ness Period Product Insecurity Scale (VNPPIS), which measures PPI.
Design:
The VNPPIS includes a 7-item gold standard scale for rigorous research applications and a 4-item short form tailored for time- or resource-constrained settings. The 7-item and 4-item scales capture four key domains of PPI: access and affordability, worry, coping, and consequences.
Methods:
Scale development included cognitive interviews (N = 18), 3 rounds of pilot testing (N = 100 each), and psychometric evaluation in a nationally fielded survey (N = 1503).
Results:
Results from the national survey showed that roughly 40% of the U.S. adult population is eligible to be screened for PPI. After fielding the VNPPIS in a national sample, results show that approximately 20% of those screened were found to experience PPI, meaning 8% of the U.S. adult population are likely to experience PPI. Results demonstrate both VNPPIS versions' strong internal consistency and evidence of face, construct, and predictive validity. PPI is moderately correlated with food insecurity and other known financial strains but emerges as a distinct material hardship. Notably, PPI is a predictor of elevated risk for anxiety and depression, outperforming food insecurity.
Conclusion:
These findings affirm the VNPPIS as a reliable and valid tool that can inform research, policy design, and interventions.
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