Development and evaluation of a crosswalk between the SF-36 physical functioning scale and Health Assessment Questionnaire disability index in rheumatoid arthritis

Table 5 Baseline to 6-month effect sizes and mean (SD) changes in physical functioning scores across levels of DAS28 treatment response in the cross-validation sample (n = 276)

	Total ES	Non- or moderate responders	Good responders	F	RV	95% CI
		(n = 142)	(n = 134)	F	RV	95% CI
HAQ-ADI
Observed	0.55	−0.20 (0.52)	−0.62 (0.58)	38.59	1.00
Predicted	0.37	−0.14 (0.54)	−0.50 (0.55)	30.12	0.78	0.35 to 1.69
HAQ-SDI
Observed	0.49	−0.17 (0.44)	−0.49 (0.49)	30.63	1.00
Predicted	0.38	−0.14 (0.53)	−0.51 (0.55)	32.38	1.06	0.44 to 2.25
PF-10
Observed	0.40	5.53 (20.15)	19.63 (20.74)	32.80	1.00
Predicted from HAQ-ADI	0.55	7.85 (19.99)	24.33 (21.98)	42.52	1.18	0.63 to 3.35
Predicted from HAQ-SDI	0.48	6.23 (15.34)	16.98 (16.68)	31.09	0.86	0.43 to 2.36

PF-10 = SF-36 physical functioning scale; HAQ-SDI = Health Assessment Questionnaire standard disability index; HAQ-ADI = Health Assessment Questionnaire alternative disability index; ES = Cohen’s d effect size; F = F-statistic from one-way ANOVA; RV = Relative validity (ratio of F-statistics compared with observed score); 95% CI = 95% bootstrap bias-corrected and accelerated confidence interval.

ISSN: 1477-7525