A comparative study of confirmatory factor analysis and Rasch Analysis as item reduction strategies for SAMHSA recovery inventory for Chinese (SAMHSA-RIC)

Background and objectives: Factor analysis has been widely used as an item-reduction method, while Rasch Analysis is also beginning to gain some popularity in scale development, with a different perspective and assumptions. In view of the lack of a comparative study, this study reports the comparative use of both strategies in reducing a newly developed inventory based on the conceptual framework of the Substance Abuse and Mental Health Services Administration (SAMHSA) Consensus Statement on the recovery of people with psychosis. Methods: The effectiveness of confirmatory factor analysis (CFA) and Rasch Analysis (RA) is assessed against the criteria of the number of items reduced, and the percentage of variance is explained for health-related quality of life measures (WHOQOL-BREF). Results: The SAMHSA Recovery Inventory for Chinese (SAMHSA-RIC) was shortened by CFA and RA from 111 to 72 and 41 items respectively. The percentage of variance explained by the RA shortened SAMHSA-RIC is higher than the CFA shortened SAMHSA-RIC (81.3 % vs 78.4 %). Conclusion: Evidence suggests that RA appears to be a viable option, in addition to, if not in replacement of, CFA.