Measuring parental barriers to childhood immunizations: the development and validation of the searching for hardships and obstacles to shots (SHOTS) instrument.

There is a plethora of literature on barriers to immunizations; however, these studies lack standardization of measurement. The aim of this study was to develop and establish an initial psychometric evaluation of an instrument to measure parental barriers to childhood immunizations. This was a cross-sectional study design. Data analysis included descriptive statistics, reliability estimates, item analysis, and factor analysis. Six hundred and fifty-five participants completed the survey. The Searching for Hardships and Obstacles to Shots instrument was developed with 60 items and reduced to 23 items thorough multiple statistical computations; the best factor model was a three-factor solution (Access to Shots, Concerns About Shots, and Importance of Shots) with a total variance explained of 59.4%. The Cronbach's alpha reliability estimates ranged from .86 to .93, and temporal stability was adequate (r = .85). This study supports exceptional initial psychometric properties of an instrument to measure parental barriers to childhood immunizations.