Development of a Phthalate Environmental Reproductive Health Literacy (PERHL) Scale

Substantial evidence exists linking phthalate exposure to adverse reproductive health outcomes. Current US federal regulations of consumer product chemicals place the onus on individuals to mitigate their exposure to phthalates, with assumptions of sufficient environmental health literacy (EHL). Few validated scales for people of reproductive age exist to evaluate phthalate-specific EHL.

Our objective is to develop a multidimensional scale characterizing latent factors of phthalate knowledge, risk perception, and self-efficacy to inform individual-level interventions for reducing phthalate exposure.

We distributed a survey with 31 items to 117 participants in the Environmental Reproductive and Glucose Outcomes (ERGO) cohort who gave birth within the last 5 years. Exploratory factor analysis (EFA) was used to identify underlying latent factors. Internal reliability was assessed via omega hierarchical coefficient. Average sum scores for each latent factor and the overall Phthalate Environmental Reproductive Health Literacy (PERHL) score were calculated. Associations between latent factors, overall PERHL score, and sociodemographic characteristics were explored using linear models.

Six latent factors were identified as follows: "Awareness of Phthalate Reproductive Health Impacts," "Uncertainty," "Protective Behavior/Risk Control," "Regulatory Interest," "Awareness of Phthalate Exposure Pathways," and "General Phthalate Knowledge." Each factor demonstrated acceptable to strong internal reliability, with coefficients ranging between 0.63 and 0.93. Non-white participants had lower scores for the "Awareness of Phthalate Reproductive Health Impacts" [$\beta$: $-0.35$, 95% confidence interval (CI): $-0.63$, $-0.07$], "Awareness of Phthalate Exposure Pathways" ($\beta$: $-0.32$, 95% CI: $-0.57$, $-0.07$), and "General Phthalate Knowledge" ($\beta$: $-0.36$, 95% CI: $-0.66$, $-0.06$), but no significant difference in scores on "Uncertainty" ($\beta$: 0.17, 95% CI: $-0.16$, 0.50), "Protective Behavior/Risk Control" ($\beta$: $-0.04$, 95% CI: $-0.36$, 0.28), or "Regulatory Interest" ($\beta$: $-0.21$, 95% CI: $-0.51$, 0.09). No associations were seen for age or educational attainment and latent or sum factors.

Six latent factors were identified for the PERHL scale. Non-white race and ethnicity was associated with lower scores for knowledge-related scale factors. https://doi.org/10.1289/EHP13128.