Determining the Internal Validity and Test Reliability of the Dream Home Assessment: A Performance-Based Measure of Executive Function for Adults with Mental Illness

Abstract

To determine the internal validity and test reliability of the Dream Home Assessment (DHA), an executive function assessment. Participants included 59 adults with and without mental illness. Rasch model of measurement was used to analyze goodness of fit and item reliability. The majority of the test items (70%) indicated good fit and the over-all tool shows minimal distortion with the Rasch model of measurement. Three test items were removed; six test items will be refined to strengthen internal validity. Items can reliably detect 2–5 levels of executive functioning ability and detect change over time. The study provides preliminary evidence of validity and reliability of the DHA.

Keywords:

• Homelessness
• mental illness
• executive function
• psychometric testing
• Rasch analysis

Acknowledgements

We would like to thank Kimberlee Baltich, MSW, Sharon A. Gutman, PhD, OTR, FAOTA, Franklin Stein, PhD, OTR/L, FAOTA, the clients at PIBLY, and the Columbia University OT graduate students and recent graduates who participated in this research.