ACR Meeting Abstracts

ACR Meeting Abstracts

  • Home
  • Meetings Archive
    • ACR Convergence 2022
    • ACR Convergence 2021
    • ACR Convergence 2020
    • 2020 ACR/ARP PRSYM
    • 2019 ACR/ARP Annual Meeting
    • 2018 ACR/ARHP Annual Meeting
    • 2017-2009 Meetings
    • Download Abstracts
  • Keyword Index
  • Advanced Search
  • Your Favorites
    • Favorites
    • Login
    • View and print all favorites
    • Clear all your favorites
  • Meeting Resource Center

Abstract Number: 1412

Validation of the Danish Version of the Stanford Health Assessment Questionnaire Disability Index and Determination of the Minimal Clinically Important Difference in a Cohort of Rheumatoid Arthritis Patients Using the Rasch Measurement Model

Lykke Midtbøll Ørnbjerg1, Karl Bang Christensen2, Alan Tennant3 and Merete Lund Hetland4, 1Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Copenhagen, Denmark, 2Department of Biostatistics, University of Copenhagen, Copenhagen, Denmark, 3Swiss Paraplegic Research, Nottwil, Switzerland, 4Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Denmark, Copenhagen, Denmark

Meeting: 2016 ACR/ARHP Annual Meeting

Date of first publication: September 28, 2016

Keywords: Health Assessment Questionnaire, Validity and outcome measures

  • Tweet
  • Email
  • Print
Session Information

Date: Monday, November 14, 2016

Session Title: Quality Measures and Quality of Care - Poster II

Session Type: ACR Poster Session B

Session Time: 9:00AM-11:00AM

Background/Purpose: The Stanford Health Assessment Questionnaire Disability Index (HAQ-DI) is a widely used patient reported outcome for functional disability in RA. Minimal clinically important differences (MCIDs) have previously been calculated based on the original ordinal HAQ-DI scores resulting in a dependence of the MCIDs on baseline scores(1), causesing limited generalizability and validity of the proposed MCIDs. The Rasch model provides a transformation of ordinal scores to an underlying latent scale with interval scale properties. This requires adequate fit of HAQ-DI data to the model. We aimed to 1) examine internal construct validity of the Danish version of the HAQ-DI (scored without correction for devices) and 2) determine a MCID of the HAQ-DI in a cohort of RA patients initiating anti-rheumatic treatment in clinical practice based on the transformed linear logit scale.

Methods: RA patients registered in the DANBIO registry at Center for Rheumatology and Spine Diseases, Copenhagen, Denmark were included in the study if HAQ-DI and Patient Global Visual Analogue Scores (PtGl) scores were available at a baseline visit and after > three months of follow-up after initiation of a) first synthetic Disease Modifying Anti Rheumatic Drug (sDMARD) (disease duration < 12 months) or 2) first biological drug (disease duration > 12 months). The Rasch model was fitted to HAQ-DI data at baseline and follow-up and item fit evaluated in separate analyses by comparing observed and expected item-restscore correlations (2). MCID was calculated as the median changes of A) the original and B) logit HAQ-DI score in the group of patients who had improved by 15-30 mm (ie. minimal improvement) on a 0-100 mm PtGl scale. 

Results: 362 RA patients were included in the study. HAQ-DI data showed acceptable fit to the Rasch model as no significant evidence of misfit was disclosed at baseline and only a single misfitting item (the “Grip” sub-item, p=0.01) was identified at follow-up. Consistent item ranking across time indicated instrument invariance. Changes in ordinal and logit HAQ-DI scores were strongly correlated (Spearmans rho = 0.935, p <0.001), but the association between them is not completely linear. Sixty-one patients had an improvement > MCID on the logit scale (0.48), but no improvement on the ordinal scale (MCID 0.250), while no patients had the opposite pattern.

Conclusion: The Danish version of the HAQ-DI scored without correcting for devices showed acceptable internal construct validity and thus a MCID based on a linear transformed scale could be calculated for this study (0.48). Application of the logit MCID classified an additional 17% of patients as having achieved a MCID compared to the MCID calculated on the ordinal scale. This finding has potential implications for the use of ordinal-based MCID and the powering of future studies. References:

1.      Doganay et al.J Rheumatol. 2016 Jan;43(1):194-202

2.      Kreiner S. Appl. Psychol. Meas. 2011;35(7):557-561.


Disclosure: L. M. Ørnbjerg, None; K. B. Christensen, None; A. Tennant, None; M. Lund Hetland, AbbVie, BMS, MSD, Roche, Pfizer, UCB, Crescendo, 2.

To cite this abstract in AMA style:

Ørnbjerg LM, Christensen KB, Tennant A, Lund Hetland M. Validation of the Danish Version of the Stanford Health Assessment Questionnaire Disability Index and Determination of the Minimal Clinically Important Difference in a Cohort of Rheumatoid Arthritis Patients Using the Rasch Measurement Model [abstract]. Arthritis Rheumatol. 2016; 68 (suppl 10). https://acrabstracts.org/abstract/validation-of-the-danish-version-of-the-stanford-health-assessment-questionnaire-disability-index-and-determination-of-the-minimal-clinically-important-difference-in-a-cohort-of-rheumatoid-arthritis-p/. Accessed February 4, 2023.
  • Tweet
  • Email
  • Print

« Back to 2016 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/validation-of-the-danish-version-of-the-stanford-health-assessment-questionnaire-disability-index-and-determination-of-the-minimal-clinically-important-difference-in-a-cohort-of-rheumatoid-arthritis-p/

Advanced Search

Your Favorites

You can save and print a list of your favorite abstracts during your browser session by clicking the “Favorite” button at the bottom of any abstract. View your favorites »

ACR Pediatric Rheumatology Symposium 2020

© COPYRIGHT 2023 AMERICAN COLLEGE OF RHEUMATOLOGY

Wiley

  • Home
  • Meetings Archive
  • Advanced Search
  • Meeting Resource Center
  • Online Journal
  • Privacy Policy
  • Permissions Policies
  • Cookie Preferences