Why sample selection matters in exploratory factor analysis: implications for the 12-item World Health Organization Disability Assessment Schedule 2.0

Table 1 Demographic characteristics of the participants and properties of the distributions of WHODAS 2.0 summary scores by country

	China	India	Mexico	Russian Federation	South Africa	Ghana
Sample size (N)^a	12,226	6,095	2,041	3,305	3,461	4,123
Demographic characteristics
Female sex	53%	49%	60%	64%	58%	47%
Age – mean (standard deviation)	63(9)	62(9)	68(9)	64(10)	63(10)	64(11)
WHODAS 2.0 Score Distribution^b
25th/50th/75th percentiles	0/2/5	5/10/16	2/5/12	3/6/12	0/5/13	2/8/15
Mean scores (standard deviation)	3.52(5.24)	11.43(8.61)	7.79(8.18)	8.28(7.74)	8.01(8.76)	9.46(8.56)
Skewness (standard error)	2.82(.02)	0.97(.03)	1.48(.05)	1.45(.04)	1.23(.04)	1.07(.04)
Percentage of participants with zero scores	32%	6%	16%	7%	26%	15%

Note. ^aOnly adults aged 50+ with no missing value in WHODAS items responses were included
^b12-item WHODAS 2.0 summary scores (calculated as the sum of item scores) can range from 0 to 48, with higher scores indicating greater activity limitations and participation restrictions

ISSN: 1471-2288