Table 4

Health outcomes for health-related quality of life with data estimates based on the Short Form-36 RAND responses

Health-related quality of life Data estimates based on SF-36 RAND responses
	Control group		Intervention group		Difference	p Value	Test
Health utility index	n	Mean (SD)	n	Mean (SD)	Mean (SE)	p Value	Test
Utility at baseline	64	0.656 (0.109)	64	0.643 (0.108)	−0.012 (0.019)	0.521	t-test
Utility at 3 months	64	0.680 (0.114)	57	0.683 (0.108)	0.003 (0.020)	0.869	t-test
Utility at 6 months	62	0.678 (0.120)	57	0.687 (0.106)	0.008 (0.020)	0.684	t-test
QALY (AUC)	55	0.340 (0.051)	47	0.342 (0.045)	0.003 (0.009)	0.776	t-test
QALY difference (controlling for baseline utility)	55		47		0.006 (0.006)	0.286	OLS regression (white adjusted SE)

Utility index scores calculated at a patient level, from SF-36, reduced to SF-6D using published utility weights.25 Quality of life (area under curve) estimated as the time integral of the utility scores over the 6-month trial period; quality of life difference estimated parametrically using ordinary least squares, controlling for baseline utility score.
AUC, area under the curve; SF-36, Short Form-36; QALY, quality-adjusted life years.