Background: The purpose of this study was to evaluate the reliability and construct validity of the Diversity Site Assessment Tool (DSAT), a self-assessment instrument designed to self-report the extent to which best practices related to recruitment of diverse patient populations during clinical trials are used.
Methods: A cross-sectional design was used. The convenience sample consisted of site representatives who are members of the Society for Clinical Research Sites and network site representatives that were approached via social media sites such as LinkedIn. A link to the survey was shared with approximately 17,000 aforementioned site representatives over a period of three months. The survey consisted of one section each for the indicators of best practice for the recruitment of diverse patient populations during clinical trials: 1) Site Overview (10 items), 2) Site Recruitment and Outreach (9 items) and 3) Patient Focused Services (6 items). These three indicators and the total of 25 items make up the DSAT. Each of the total 25 items on DSAT required participants to self-report on a 6-point scale. The fourth section collected background information about the participant and their site. After the survey was closed, two types of summative scores were compiled, one for each of the indicators and an overall summative DSAT score (range from 25-150). Higher summative scores on each indicator and the overall DSAT are reflective of increased use of best practices for the recruitment of diverse patient population during clinical trials. Internal consistency reliability (Cronbach’s alpha) and construct validity for the entire sample were evaluated and are reported. Bivariate and multivariate statistics were conducted to examine the relationship between site characteristics and their summative indicator and DSAT overall scores.
Results: The instrument was deemed to have exceptional reliability. Cronbach's alpha coefficient for internal consistency reliability for the entire sample was 0.929. Construct validity established using the exploratory factor analysis indicated a three component solution accounting for 49% of the explained variance. There was no statistically relationship between site characteristics and their summative indicator and DSAT overall scores.
Conclusion: The DSAT has exceptional reliability and good construct validity. When paired with the findings that site characteristics have no statistical relationship with the DSAT indicators and overall summative scores, it is contended that this instrument could be used by different site backgrounds as a self-assessment measure to evaluate the extent of the use of best practices related to recruitment of diverse patient populations during clinical trials. The rigorous development of the instrument and exceptional statistical results make the tool easily the highest standard of measurement available related to this construct.