Table 5.

Exploratory factor analysis of the Persian version of WAI questionnaire using principal component extraction with varimax rotation

Question	Components
	1	2	3
Item 1: Current work ability compared with the lifetime best	0.05	0.75a	0.19
Item 2.1: Current work ability in relation to physical demands	0.15	0.81a	0.23
Item 2.2: Work ability in relation to mental demands	0.11	0.83a	0.16
Item 3: Number of current diseases diagnosed by physician	0.08	0.10	0.67a
Item 4: Estimated work impairment due to diseases	0.16	0.22	0.80a
Item 5: Sick leave during the past year (12 mo)	0.01	0.13	0.71a
Item 6: Own prognosis of work ability 2 y from now	0.29	0.24	0.55a
Item 7.1: Enjoying daily tasks	0.86*	0.10	0.13
Item 2.2: Activity and life spirit	0.87*	0.13	0.13
Item 7.3: Optimistic about the future	0.80*	0.07	0.11
Variance of the component (%)	37.6	16.5	10.9
Total cumulative variance (%)		65.02

^aSignificant component for each factor (factor loading ≥0.4)