Replication and validation of higher order models demonstrated that a summary score for the EORTC QLQ-C30 is robust

详细信息    查看全文

• 作者：Johannes M. Giesinger^a ; ¹ ; Jacobien M. Kieffer^a ; ¹ ; Peter M. Fayers^b ; ^c ; Mogens Groenvold^d ; ^e ; Morten Aa. Petersen^d ; Neil W. Scott^b ; Mirjam A.G. Sprangers^f ; Galina Velikova^g ; Neil K. Aaronson^a ; ^{n.aaronson@nki.nl" class="auth_mail" title="E-mail the corresponding author} ; on behalf of the EORTC Quality of Life Group
• 关键词：Health-related quality of life ; Questionnaires ; EORTC QLQ-C30 ; Measurement model ; Higher order factor scores ; Confirmatory factor analysis
• 刊名：Journal of Clinical Epidemiology
• 出版年：2016
• 出版时间：January 2016
• 年：2016
• 卷：69
• 期：Complete
• 页码：79-88
• 全文大小：566 K

文摘

To further evaluate the higher order measurement structure of the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 (QLQ-C30), with the aim of generating a summary score.

Study Design and Setting

Using pretreatment QLQ-C30 data (N = 3,282), we conducted confirmatory factor analyses to test seven previously evaluated higher order models. We compared the summary score(s) derived from the best performing higher order model with the original QLQ-C30 scale scores, using tumor stage, performance status, and change over time (N = 244) as grouping variables.

Results

Although all models showed acceptable fit, we continued in the interest of parsimony with known-groups validity and responsiveness analyses using a summary score derived from the single higher order factor model. The validity and responsiveness of this QLQ-C30 summary score was equal to, and in many cases superior to the original, underlying QLQ-C30 scale scores.

Conclusion

Our results provide empirical support for a measurement model for the QLQ-C30 yielding a single summary score. The availability of this summary score can avoid problems with potential type I errors that arise because of multiple testing when making comparisons based on the 15 outcomes generated by this questionnaire and may reduce sample size requirements for health-related quality of life studies using the QLQ-C30 questionnaire when an overall summary score is a relevant primary outcome.