Skip to main content

Table 4 Stepwise regression model for predictors of change in HAQ-DI from month 6 to month 0 (P < 0.001)

From: Use of a “critical difference” statistical criterion improves the predictive utility of the Health Assessment Questionnaire-Disability Index score in patients with rheumatoid arthritis

VariableCoefficienta,bPartial R2Cumulated R2
Change in pain (month 6 – month 0)c0.103330.278930.2789
Baseline HAQ-DI−0.358210.054360.333
Baseline pain0.063820.046690.3800
Age0.004930.020330.4003
Change in DAS28 (month 6 – month 0)c0.064880.011150.4115
Disease duration0.006450.008130.4196
Body mass index0.007300.005370.4250
Baseline DAS280.041430.004500.4295
  1. Model intercept = −0.62463
  2. Abbreviations: DAS28 Disease Activity Score-28 joints, HAQ-DI Health Assessment Questionnaire-Disability Index
  3. aThe coefficient shows the influence for each unit of the predictor’s scale
  4. bBecause a negative value for HAQ-DI month 6 – month 0 indicates an improvement, variables with negative coefficients are positive predictors and those with positive coefficients are negative predictors
  5. cHigher values on these scales represent greater impairment, so higher values for month 6 – month 0 correspond to lack of improvement and are a negative predictor for improvement in HAQ-DI