Factor structure and psychometric properties of english and spanish versions of the edinburgh postnatal depression scale among Hispanic women in a primary care setting.

Postpartum depression (PPD) is prevalent, occurring in 10%–15% of mothers (Gavin et al., 2005; Vesga-Lopez et al., 2008). According to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR; American Psychiatric Association [APA], 2000), PPD refers to a major depressive episode that begins within the 4 weeks after childbirth, although researchers increasingly view major depressive disorder (MDD) within the first year to constitute PPD (O’Hara, 2009). The DSM-IV-TR (APA, 2000) symptom criteria for PPD are identical to the symptom criteria for a major depressive episode without postpartum onset, including somatic symptoms. Somatic symptoms such as sleep disturbances and weight and appetite changes are common during the postpartum period, even in the absence of other depressive symptoms. This overlap between MDD diagnostic criteria and common somatic experiences among women during the postpartum period has raised concern about the possibility of misinterpreting such experiences as depressive symptoms, which could lead to false positives on PPD screenings. In response to this concern, the Edinburgh Postnatal Depression Scale (EPDS; Cox, Holden, & Sagovsky, 1987), a widely used 10-item self-report measure, was developed to screen for major depression in the postpartum period without confounding somatic symptoms that are common to the postpartum period. Although the EPDS has been conceptualized as a unidimensional measure of PPD symptoms (Cox et al., 1987), research indicates that it likely assesses multiple factors including depression, anxiety (for a review, see Phillips, Charles, Sharpe, & Matthey, 2009), anhedonia (Lee King, 2012; Chabrol & Teissedre, 2004; Montazeri, Torkan, & Omidvari, 2007; Tuohy & McVey, 2008), and suicide (Brouwers, van Baar, & Pop, 2001; Jomeen & Martin 2005; Ross, Gilbert Evans, Sellers, & Romach, 2003; Tuohy & McVey, 2008). Previous research examining the factor structure of the EPDS has generally supported two-or three-factor models. In studies using exploratory techniques such as principal components analysis (PCA) or exploratory factor analysis (EFA), support has been obtained for three-factor models comprising depression, anxiety, and suicide (Brouwers et al., 2001; Ross et al., 2003) and depression, anxiety, and anhedonia (Tuohy & McVey, 2008). Other studies using PCA or EFA, including a study conducted among mothers in Spain (Maroto Navarro, Garcia Calvante, & Fernandez Parra, 2005), found support for a two-factor model comprising depression and anxiety (Phillips et al., 2009). Based on the findings from EFA on the EPDS, recent studies have used confirmatory factor analysis (CFA) to evaluate and compare the fit of proposed structural models. For example, Jomeen and Martin (2005) used CFA to evaluate a one-factor model, multiple two-factor models, and multiple three-factor models among 101 women in the United Kingdom. A two-factor model comprising depression and anxiety provided the best fit to the data. Phillips et al. (2009) used EFA and CFA to evaluate a one-factor model and multiple two-factor models among 309 mothers in Australia. Each of the two-factor models provided an adequate fit to the data and provided a superior fit than the one-factor model. A two-factor model comprised of Depression and Anxiety provided the best fit. Recently, Lee King (2012) used CFA to evaluate the fit of five structural models in a sample of 169 postpartum African American women. A three-factor model comprising depression, anxiety, and anhedonia provided the best fit to the data. Thus, research examining the factor structure of the EPDS consistently supports either a two-or three-factor model over a one-factor model. To date, however, no study has examined the factor structure of the EPDS among Hispanic women in the United States. This is an important gap in the knowledge base because of the growing size of the Hispanic population in the United States and the high rate of childbirth among Hispanic women in the United States. Hispanics currently represent the nation’s largest ethnic minority group (U.S. Census Bureau, 2011) and had the highest birth rate of any ethnic group in the United States from 1990 to 2007, indicating that (a) the population continues to grow at a rapid pace (U.S. National Center for Health Statistics, 2010) and (b) a large percentage of the population includes women of childbearing age. Additionally, Hispanic women have been found to report significantly higher levels of post-partum depressive symptoms and to be more likely to meet criteria for a diagnosis of PPD than non-Hispanic White and non-Hispanic Black women (Howell, Mora, Horowitz, & Leventhal, 2005; Liu & Tronick, 2013). These population and depression estimates highlight the need to ensure the appropriateness of PPD measures for Hispanic women in the United States. The purpose of the current study was to examine the factor structure and psychometric properties of the EPDS among Hispanic mothers in the United States. The first aim was to identify the best fitting structural model for Hispanic mothers who completed the EPDS in English and Hispanic mothers who completed the EPDS in Spanish from six different models guided by past research: the five separate models evaluated in Lee King (2012) and a two-factor model previously supported among mothers in Spain (Maroto Navarro et al., 2005). We selected these six models because they included the one-, two-, and three-factor models evaluated in prior studies of the EPDS among non-Hispanic women (Lee King, 2012), as well as the two-factor model supported for the Spanish version of the EPDS (Maroto Navarro et al., 2005). The second aim was to examine factorial invariance across mothers who completed the EDPS in English and mothers who completed the EPDS in Spanish. Finally, we examined the internal reliability of the total EPDS score and EPDS factor scores and explored the scale’s convergent validity via associations between the EPDS scores and history of mental health treatment.