Development and Validation of a Multidimensional Experimental Screening Instrument to Measure Multiple Barriers Associated with Adult dietary Practices: A Secondary Analysis of NHANES Datasets 2011-2012

Abstract

Dietary practices, which are complex and reflective of one’s life experience, are influenced by intrinsic and extrinsic factors. Given that good nutrition is the underpinning of good health, it is prudent to measure factors associated with dietary practices. While instruments are available to assess factors associated with diet, none are designed to simultaneously measure the multi-dimensional nature of barriers associated with dietary practices. The aim of this dissertation was to develop a multidimensional instrument that can be used as a screening tool by practitioners to determine barriers associated with adult dietary practices. This dissertation compendium includes four manuscripts reporting results from: 1) an integrative review describing food insecurity interventions for African Americans in the United States; 2) a study that established content validity for a hypothesized multidimensional instrument designed to identify barriers to dietary practices; 3) an analysis to identify constructs within and validate the hypothesized multidimensional instrument; and 4) an exploratory secondary analysis to examine the relationships between dietary health status (DHS) and selected participant demographic characteristics and clinical outcomes. Results from the integrative review (Manuscript 1) suggested that multi-level interventions that address barriers influencing dietary access and choices demonstrated the greatest efficacy in improving access to healthful foods compared to one-dimensional interventions. Manuscript 2 established content validity for 12 theory-based domains comprised of variables that represent barriers associated with adult dietary practices. Manuscript 3 developed the DHS instrument, designed to measure barriers associated with dietary practices and tested the psychometric properties of this instrument. Exploratory factor analysis described in Manuscript 3 revealed adequate construct and internal validity of the DHS instrument and for the 10 subscales that comprise DHS. Manuscript 4 showed that participants who are older than 45 years, minorities, (Black, Hispanic or Other race), live in larger households, are not married, and have abnormal A1c or blood pressure levels were more likely to have lower DHS scores compared to their counterparts. These findings suggest these groups might have more barriers to adhering to healthful dietary practices than their counterparts, possibly increasing their risk for chronic diseases. The knowledge gained from this dissertation will guide future refinement of the DHS instrument. Ultimately, refining the DHS instrument so that it can accurately identify multiple barriers to dietary practices could have far reaching implications for education, practice, and policy