ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on Twitter

Kidney Week

Abstract: TH-PO661

CKD and Anemia Questionnaire (CKD-AQ): A Reliable and Sound Patient-Reported Outcome Measure for Use in Patients With Anemia of CKD

Session Information

  • Anemia and Iron Metabolism
    November 03, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
    Abstract Time: 10:00 AM - 12:00 PM

Category: Anemia and Iron Metabolism

  • 200 Anemia and Iron Metabolism

Authors

  • Keeley, Tom J H, GlaxoSmithKline, Brentford, United Kingdom
  • Chen, Wen-Hung, GlaxoSmithKline, Collegeville, Pennsylvania, United States
  • Refoios Camejo, Rodrigo, GlaxoSmithKline, Brentford, United Kingdom
  • Okoro, Tony, GlaxoSmithKline, Collegeville, Pennsylvania, United States
  • Bhatt, Purav Rahulkumar, GlaxoSmithKline, Collegeville, Pennsylvania, United States
  • Vernon, Margaret, Evidera, London, United Kingdom
  • Hsieh, Ray, Evidera, Bethesda, Maryland, United States
  • Stringer, Sonja M., Evidera, Bethesda, Maryland, United States
  • Johansen, Kirsten L., Hennepin Healthcare, University of Minnesota, Minneapolis, Minnesota, United States
Background

CKD-AQ is the first patient-reported outcome (PRO) measure designed specifically to assess the symptom burden of anemia of CKD. It includes 21 items that give three domain scores (Tired/Low Energy/Weak, 10 items; Chest Pain/Shortness of Breath, 4 items; Cognitive, 3 items) and four individual item scores (difficulty sleeping, difficulty standing for long periods of time, severity-shortness of breath while sitting/resting, time with shortness of breath while not doing activity). We report on the measurement properties of CKD-AQ in patients with anemia of CKD.

Methods

Two separate samples (n=399, n=450) of combined data from patients with anemia of CKD not currently receiving dialysis and patients initiating dialysis were used. Factor structure was identified and tested using exploratory and confirmatory factor analyses (EFA/CFA). Other assessments: internal-consistency and test-retest reliability; construct validity; responsiveness; differential item functioning (DIF) analysis between patients on and not on dialysis.

Results

The three multi-item domain structure identified through EFA was confirmed with CFA, with factor analytic fit statistics above or just slightly below the recommended standard. Internal-consistency reliability was good (Cronbach’s alpha 0.734–0.955) and test-retest reliability was adequate (intraclass correlation coefficient 0.555–0.701) for all scales. Convergent validity analysis showed hypothesized associations with Short-Form (SF)-36, Euroqol 5-dimension, and Work Productivity and Activity Impairment scores. CKD-AQ scores were significantly different among Patient Global Impression of Severity groups, supporting known-groups validity. Supporting responsiveness, improvements in CKD-AQ scale scores were consistently associated (r>0.3) with improvements in multiple external validation anchors (including SF-36 domains and component scores). There was no systematic difference in the way that dialysis and non-dialysis patients answered the CKD-AQ items.

Conclusion

CKD-AQ is a valid, fit-for-purpose and psychometrically sound PRO tool suitable for use in patients with anemia of CKD. The measure is licensable and ready for future use.

Funding

  • Commercial Support