Application of the health assessment questionnaire disability index to various rheumatic diseases

Self Cite

Objective. To evaluate the crosscultural measurement equivalence of the US and Dutch Health Assessment Questionnaire II (HAQ-II) in rheumatoid arthritis (RA). Methods. Item response theory (IRT) analyses were performed on US (n ‫؍‬ 18,747) and Dutch (n ‫؍‬ 1,022) HAQ-II data to evaluate the equivalence of crosscultural item performance. The observed inconsistencies were modeled by assigning country-specific item parameters to biased items. The impact of crosscultural item bias on the comparability of the Dutch and US total scores was analyzed by evaluating the agreement between physical function levels estimated from an IRT model with country-specific item parameters for biased items and physical function levels estimated from the original model that did not account for cultural bias. Results. Two items showed significant crosscultural bias. However, the agreement in physical function estimates between the respecified and original models was very high, with an intraclass correlation coefficient >0.99 and Bland-Altman limits of agreement ranging from ؊0.08 to ؊0.01 on a latent scale with a mean of 0 and an SD of 1. Conclusion. This study suggests that the Dutch and US HAQ-II produce total scores that can be interpreted interchangeably across countries in RA studies, despite some minor bias at the item level.

Section: Methodsmentioning

confidence: 99%

Crosscultural Measurement Equivalence of the Health Assessment Questionnaire II

Voshaar

Glas

Klooster

et al. 2013

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“…Both the 28-and 38-joint counts of tenderness and swelling had to fit the GPCM before the contribution of the forefoot joints could be analyzed. This fit was analyzed with Lagrange Multiplier Q1 tests (15), where absolute effect sizes of Ͻ0.10 were seen as an indication of good item-model fit (16,17).…”

Section: Methodsmentioning

confidence: 99%

Contribution of assessing forefoot joints in early rheumatoid arthritis patients: Insights from item response theory

Siemons¹,

Klooster²,

Taal³

et al. 2013

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Objective. To evaluate the contribution of assessing forefoot joints to the measurement range and measurement precision of joint counts in early rheumatoid arthritis (RA) using item response theory. Methods. Baseline measures of tender and swollen joint counts were analyzed in 459 early RA patients from the Dutch Rheumatoid Arthritis Monitoring remission induction cohort. The contribution of forefoot joints was studied by evaluating their effect on the measurement range and measurement precision of measures based on 28-joint counts. In addition, the alignment between the patient and joint distributions was investigated to determine whether the forefoot joints were informative for measuring joint tenderness or swelling of an early RA patient. Results. In total, 233 patients (50.76%) experienced tenderness and 200 patients (43.57%) experienced swelling in >1 forefoot joint. Forefoot joints were more informative for measuring joint tenderness than joint swelling, but did not significantly improve the measurement range and measurement precision of the 28-joint counts. Furthermore, including forefoot joints did not remove the existing discrepancy between the joint and patient distributions in both joint counts. Conclusion. Forefoot joints were frequently affected on an individual level, but did not significantly improve the measurement range or precision of 28-joint counts in patients with early RA. From a measurement perspective, reduced joint counts are appropriate for use on a population level. The contribution of assessing forefoot joints on an individual level requires further investigation. Additionally, the results should be cross-validated in patients with longer disease durations to determine whether the pattern of joint involvement is similar in later stages of RA.

“…However, the relationship between PF scores and the latent PF construct may differ between patients with different cultural backgrounds or between patients with different diseases. For example, previous research has shown that HAQ DI items function differently between patients with gout, osteoarthritis, and RA (7). Therefore, the generalizability of a crosswalk needs to be tested before it can be used in a new setting.…”

Section: Introductionmentioning

confidence: 99%

Linking Physical Function Outcomes in Rheumatology: Performance of a Crosswalk for Converting Health Assessment Questionnaire Scores to Short Form 36 Physical Functioning Scale Scores

Voshaar

Klooster

Taal

et al. 2014

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Objective. To evaluate the reliability of a crosswalk, developed in The Netherlands, between the Health Assessment Questionnaire (HAQ) disability index (DI) and the Short Form 36 physical functioning scale (PF-10) in a sample of patients with various rheumatic diseases in the US. Methods. Baseline data from patients with rheumatoid arthritis (RA; n ‫؍‬ 29,020), fibromyalgia (FM; n ‫؍‬ 3,776), and systemic lupus erythematosus (SLE; n ‫؍‬ 1,609) participating in the National Data Bank for Rheumatic Diseases were analyzed. Reliability of the crosswalk was evaluated by calculating intraclass correlation coefficients (ICCs), and agreement between observed and predicted scores was evaluated using the Bland-Altman approach. Results. The crosswalk produced reliable conversions for both the HAQ DI (ICC range 0.70 -0.77) and PF-10 (ICC range 0.73-0.78) in all 3 disease groups. The mean difference between observed and expected scores was close to zero in US patients with RA. For all 3 disease groups, the limits of agreement were fairly wide and conversion at the level of individual patients is not recommended. Conclusion. The crosswalk produced reliable conversions at the group level in a crosscultural setting and can be used to convert HAQ DI to PF-10 scores and vice versa in US patients with RA, FM, or SLE.