Table 1.

Subjects by ethnic group, and examination status, by age and gender

Ethnicity	Population in study areas		People selected		People examined		Not available		Refused		Unable		Total examined
	n	%	n	%	n	%	n	%	n	%	n	%	n	%
Han	641,783	(46.2)	1775	42.8	1712	(96.5)	45	(2.5)	8	(0.5)	10	(0.6)	1712	100
Kazak	551,318	(39.7)	1837	(44.3)*	1747	(95.1)	80	(4.4)**	6	(0.3)	4	(0.2)	1747	100
Yugur	51,467	(3.7)	108	(2.6)	105	(97.2)	3	(2.8)	0	0.0	0	0.0	105	100
Other	145,862	(10.5)	430	(10.4)	413	(96.1)	11	(2.6)	2	(0.5)	4	(I0.9)	413	100
Total	1,390,430	(100)	4150	(100)	3977	(95.8)	139	(3.4)	16	(0.4)	18	(0.4)	3977	100
	Male				Female				Total
Age	Population in study areas		People Examined		Population in study areas		People Examined		Population in study areas		People Examined
	n	%	n	%	n	%	n	%	n	%	n	%
50–59 years	11,771	45.4	727	40.2	11,730	44.1	905	41.7	23,501	44.8	1632	41.0
60–69 years	8495	32.8	585	32.3	8822	33.2	749	34.5	17,317	33.0	1334	33.5
70–79 years	4675	18.0	381	21.1	5020	18.9	387	17.9	9695	18.5	768	19.3
80+ years	985	3.8	116	6.4	1012	3.8	127	5.9	1997	3.8	243	6.1
Total	25,926	100	1809	100	26,584	100	2168	100	52,510	100	3977	100

*It seemed we selected less Han Chinese and more Khazak compared their proportion of total population in study areas (p < 0.5)

**p < 0.01 Khazak people had highest rate of “not available” as they were mostly nomadic