Assessing psychological adjustment and cultural reintegration after military service: development and psychometric evaluation of the post-separation Military-Civilian Adjustment and Reintegration Measure (M-CARM)

BACKGROUND: The transition out of military service and subsequent reintegration to civilian life has been established as a period associated with an increased risk of psychological adjustment difficulties, psychiatric disorders and suicide risk, yet no tool exists to measure cultural and psychological adjustment following permanent separation from the military. This study describes the two-phase mixed-methods development and validation of the self-report Military-Civilian Adjustment and Reintegration Measure (M-CARM). METHODS: In Phase I, four focus groups (n = 20) and semi-structured one-on-one interviews (n = 80) enabled thematic analysis and generation of 53 initial items that were reviewed by an expert multidisciplinary panel (n = 12) and piloted for clarity and relevance in an Australian service-veteran sample (n = 11). In Phase II, psychometric properties of the 47 items resulting from Phase I were evaluated with online assessment of a convenience sample of transitioned Australian Defence Force veterans (n = 725). Analyses included exploratory and confirmatory factor analyses, as well as evaluation of test-retest reliability, internal consistency, and convergent, divergent and discriminant validity. RESULTS: Exploratory factor analysis on a randomized split-half sample (n = 357), resulted in a 21-item, five-factor solution of Purpose and Connection, Help seeking, Beliefs about civilians, Resentment and regret, and Regimentation, explaining 53.22% of the variance. Confirmatory factor analysis (n = 368) verified this factor structure without modification (χ2 = 304.96, df = 160; CFI = .96, TLI = .94, NFI = .91, RMSEA = .05). Strong convergent, divergent and discriminant validity was demonstrated as M-CARM scores significantly correlated with related constructs assessed by standardised clinical measures as well as differentiated groups based on three binary reintegration items, with large effect sizes (d = > 1). Strong test-retest reliability for the total score (n = 186, r = .93) and excellent internal consistency (n = 725, a = .90) were also found. CONCLUSIONS: Results provide promising evidence the M-CARM is a valid, reliable measure of psychological and cultural reintegration to civilian life, with potential for considerable clinical and research application. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12888-020-02936-y.