Reliability & Validity


The internal consistency of the BIMF has been demonstrated in a variety of subpopulations of women including women who screened positive for postpartum depression (Barkin et al., 2010, 2014), general OB/GYN patients (Barkin et al., 2017, Heberlein et al., 2016) and mothers whose infants were admitted to the Neonatal Intensive Care Unit (Barkin et al., 2019).  The Cronbach’s alpha for the full 20-item scale has ranged between .83-.87 in published reports, indicating strong inter-item agreement.

Content Validity:

The BIMF items were developed based on the thoughts and experiences of new mothers.  Because new mothers are experiencing the condition of interest (functioning in new motherhood), they are best suited to inform the content of the measure (Fayers & Hays, 2005).  This patient-centered approach promotes content validity.  While new mothers supplied the core conceptual content, the results of a literature search were also utilized to ensure that no domains of postpartum functioning were omitted from the BIMF (Barkin et al., 2010).  Finally, a panel comprised of experts in the areas of women’s health, mental health, reproductive health, survey development, psychometrics and qualitative analysis were convened to review the measure for content and word choice (Barkin et al., 2010).  Suggestions from the expert panel were incorporated into the final version of the BIMF.

Language Validity & Comprehension:

The BIMF was the focus of a cognitive interviewing study where 24 new mothers evaluated the questionnaire items for meaning (Barkin et al., 2015).  Cognitive interviewing is a best practices approach to survey development (Willis, 2004); it is used to “study the manner in which targeted audiences understand, mentally process, and respond to the materials we present—with a special emphasis on potential breakdowns in this process” (Willis, 2004). In short, we studied the correlation between the developer’s intent and the respondents’ understanding of the 20 BIMF items. The research team found that even in a socioeconomically disadvantaged group of women, the BIMF items were easy to understand and complete (Barkin et al., 2015).

Construct Validity:

Construct validity has been demonstrated for the BIMF across various subgroups of women.

In women who screened positive for depression (Edinburgh Postnatal Depression Scale Score ≥ 10 (Cox, Holden & Sagovsky, 1987)) at the outset of the Identification and Therapy of Postpartum Depression Study (Screening Study; R01 MH071825, K Wisner, PI) the following associations have been observed (Barkin et al., 2010, 2014, 2015, 2017):

The BIMF was directly and significantly associated with:

  • Maternal gratification – Gratification Checklist (GRAT; (Mercer, 1985, Russell, 1974))
  • Mental functioning – Short-Form Health Survey Mental Functioning Component (SF-12 Mental; Ware, Kosinski, Keller, 1996)
  • Global Functioning – Global Assessment Scale (GAS; Endicott et al., 1976)

The BIMF was inversely and significantly associated with:

  • Depression – Hamilton Rating Scale for Depression (HRSD-17; Hamilton, 1960).
  • Atypical Depression – Hamilton Depression Rating Scale with Atypical Depression Supplement (SIGH-ADS; Williams & Terman, 2003)
  • Maternal age

In a population of low-income OB/GYN patients, the following associations were observed (Barkin et al., 2017):

The BIMF was inversely and significantly associated with:

  • Depression – Edinburgh Postnatal Depression Scale (EPDS; Cox, Holden & Sagovsky, 1987)

In a population of mothers whose infants were admitted to the Neonatal Intensive Care Unit, the following associations were observed (Barkin et al., 2019):

The BIMF was inversely and significantly associated with:

  • Depression – Edinburgh Postnatal Depression Scale (EPDS; Cox, Holden & Sagovsky, 1987)
  • Parental Stress – Parental Stress Scale: Neonatal Intensive Care Unit (PSS:NICU; Miles, Funk & Carlson, 1993)

Additional Evidence of Validity:

  • A 19 point increase in the BIMF total score was observed in patients who completed Mother Baby Connections, an intensive, outpatient perinatal mental health program launched at Drexel University in Philadelphia, Pennsylvania (Gellar et al., 2018).
  • Preliminary work with the Lauren & Mark Rubin Visiting Moms® program of Jewish Family & Children Service in Waltham, Massachusetts indicates a significant, double-digit average increase in BIMF scores from program entry to program completion (manuscript in progress). Visiting Moms® aims to support new parents throughout the first year of parenthood through visits with trained volunteers; the visits are tailored to support each mother’s unique needs.
  • In women with inadequate social support, those participating in group prenatal care had BIMF scores that were almost 6 points higher (104.1 vs. 98.5) than those in individual prenatal care (Heberlein et al., 2015). This is consistent with the emerging literature regarding the benefits of group prenatal care, relative to traditional care.