The reliability and validity of the SF-8 with a conflict-affected population in northern Uganda

Table 2 Principal component analysis of the SF-8 (N = 1206)

	SF-8 Items	Hypothesized association *		General US Population **		Uganda IDP Population
		Physical	Mental	Physical	Mental	Physical	Mental
1	General health	+++	+	0.74	0.30	0.79	0.21
2	Physical functioning	+++	+	0.87	0.17	0.78	0.20
3	Role – physical	+++	+	0.85	0.28	0.79	0.28
4	Bodily pain	+++	++	0.75	0.21	0.78	0.32
5	Vitality	++	++	0.58	0.48	0.68	0.16
6	Social functioning	++	+++	0.53	0.70	0.34	0.70
7	Role – emotional	++	+++	0.42	0.77	0.22	0.85
8	Mental health	+	+++	0.07	0.91	0.16	0.88
Variance explained †				72.3%		67.5%

Abbreviations: IDP; internally displaced person; MCS, mental component summary; PCS, physical component summary;
* Hypothesised association for general US population by SF-8 developers (Ware et al, 2001):
+++ Strong association (r ≥ 0.70)
++Moderate to substantial association (r 0.30 – 0.70)
+ Weak association (r ≤ 0.30)
** General US population data collected by SF-8 developers (Ware et al, 2001).
† Variance explained = percent of the total measured variance in the SF-8 items explained by the two principal components.

ISSN: 1477-7525