Journal of Patient-Reported Outcomes

Table 3 Convergent validity: Spearman rank-order correlation coefficients between WPAI domains and criterion measures of health-related quality of life

From: Psychometric validation of the work productivity and activity impairment questionnaire in ulcerative colitis: results from a systematic literature review

	WPAI Domain
Criterion Measure	Absenteeism	Presenteeism	Overall Work Impairment	Activity Impairment
SIBDQ
Bowel symptoms	−0.47	−0.68	− 0.68	−0.55
Systemic symptoms	−0.13	−0.31	− 0.31	−0.46
Emotional function	−0.15	−0.40	− 0.38	−0.49
Social function	−0.36	−0.64	− 0.63	−0.68
Median correlation	−0.26	*−0.52*	*− 0.51*	*−0.52*
SF-12v2
Physical functioning	−0.22	− 0.28	− 0.28	−0.35
Role physical	−0.38	−0.57	− 0.57	−0.50
Bodily pain	−0.52	−0.54	− 0.54	−0.55
General health	−0.07	−0.15	− 0.12	−0.34
Vitality	−0.33	−0.31	− 0.31	−0.44
Social functioning	−0.37	−0.35	− 0.36	−0.44
Role emotional	−0.35	−0.46	− 0.46	−0.41
Mental health	−0.18	−0.17	− 0.17	−0.33
Median correlation	−0.34	−0.33	− 0.34	*−0.43*

SF-12v2 SF-12v2 Health Survey, SIBDQ Short Inflammatory Bowel Disease Questionnaire, WPAI Work Productivity and Activity Impairment questionnaire
Note: all data in this table are from Yarlas et al (2015a) [36]
Values printed in BOLD indicate correlations satisfying the definition of convergent validity (≥|0.40|) [24]

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