Table 1.

Convergent validity analysis: correlation matrix (Spearmanʼs rho) of the ASAS HI Questionnaire versus anthropometric measures (BASMI), specific and generic HRQoL questionnaires (ASQoL and EQ-5D), functional disability (BASFI) and disease activity scores (BASDAI, ASDAS-CRP and SASDAS)

	ASQoL	BASDAI	BASFI	BASMI	EQ-5D	SASDAS	ASDAS-CRP
ASAS HI	0.784	0.568	0.671	0.303	−0.460	0.640	0.564
	<0.0001	<0.0001	<0.0001	0.0003	<0.0001	<0.0001	<0.0001
ASQoL		0.645	0.626	0.271	−0.436	0.689	0.620
		<0.0001	<0.0001	0.0012	<0.0001	<0.0001	<0.0001
BASDAI			0.586	0.192	−0.453	0.868	0.757
			<0.0001	0.0229	<0.0001	<0.0001	<0.0001
BASFI				0.578	−0.329	0.723	0.624
				<0.0001	0.0001	<0.0001	<0.0001
BASMI					−0.160	0.321	0.289
					0.0590	0.0001	0.0005
EQ-5D						−0.407	−0.418
						<0.0001	<0.0001
SASDAS							0.845
							<0.0001

Spearman rank correlation coefficient

Abbreviations: ASAS HI Assessment of SpondyloArthritis international Society Health Index, ASQoL Ankylosing Spondylitis Quality of Life Scale, BASDAI Bath Ankylosing Spondylitis Disease Activity Index, BASFI Bath Ankylosing Spondylitis Functional Index, BASMI Bath Ankylosing Spondylitis Metrology Index,EQ-5D EuroQoL Five Dimensional Questionnaire, SASDAS Simplified Ankylosing Spondylitis Disease Activity Index, ASDAS Ankylosing Spondylitis Disease Activity Score, CRP C-Reactive Protein