Psychometric Properties of the Korean Version of the Inner Strength Questionnaire

Purpose: The purpose of this study is to verify the validity and reliability of the the Inner Strength Questionnaire-Korean version (ISQ-K). Methods: The questionnaire was provided to breast cancer survivors in two Cancer centers in Gyeonggi, Korea and 167 surveys were analyzed. Data were analyzed by CVI for contents validity, confirmative factor analysis for construct validity and correlation for criteria validity. Test-retest analysis and Cronbach's a was calculated for reliability. Results: Content validity was excellent. Confirmative factor analysis was performed on 4 factors based on the original structures and the goodness-of-fit was as followed: chi(2)=784.01, df=318, RMSEA=.09, TLI=.78, CFI=.72, GFI=.72. Standard errors of variance ranged from 0.06 to 0.15. Inner strength was correlated positively with resilience (r=.47, p<.001). Test-retest reliability was 0.90 and internal consistency was indicated by Cronbach alphas of 0.85 for inner strength. Conclusion: We conclude that the ISQ-K would be a valuable tool in evaluating inner strength among breast cancer survivors.