Table 5.

Known-groups validity: PROMIS SD-SF-8b total score by PGI-S SD categories at baseline

PGI-S SD categories	N	LS mean (SE)	95% CI	p value	Contrast p value
No problems	70	16.94 (0.60)	15.76, 18.13	< 0.0001
Mild problems	233	22.47 (0.33)	21.82, 23.12		< 0.0001
Moderate problems	484	27.31 (0.23)	26.86, 27.76		< 0.0001
Severe problems	232	33.04 (0.33)	32.39, 33.70		< 0.0001

p value is based on analysis of variance comparisons with alpha = 0.05 level. Contrast p value comparisons examined adjacent PGI-S SD groups, i.e., “no problems” versus “mild problems”, “mild problems” versus “moderate problems”, and “moderate problems” versus “severe problems”

CI Confidence interval, LS Least squares, PGI-S SD Patient Global Impression of Severity Sleep Disturbance, PROMIS SD-SF-8b Patient-Reported Outcomes Measurement Information System Sleep Disturbance – Short Form 8b, SE Standard error