Table 1. Results of screening for PEx among 477,627 pupils in 406 primary schools in 31 towns in Dongguan.

Towns	Primary schools (number)	Number of screened individuals			Total No.	PEx (No.)	Incidence (‰)
		2013-2014	2012-2013
Humen	28	1,743	5,718		7,461	4	0.536
Nancheng	18	1,182	3,876		5,058	1	0.198
Guancheng	9	580	899		2,479	3	1.211
Shilong	7	463	1,521		1,984	1	0.504
Shijie	14	4,239	18,148		22,387	35	1.563
Chashan	13	3,758	15,288		19,046	21	1.102
Houjie	23	6,470	23,159		29,629	5	0.169
Shatian	7	2,408	7,120		9,528	1	0.105
Daojiao	8	1,953	10,284		12,237	0	0
Hongmei	8	300	1,944		2,244	0	0
Mayong	9	1,157	6,713		7,870	0	0
Wangniudun	6	1,367	5,907		7,274	0	0
Zhongtang	13	447	2,453		2,900	2	0.345
Gaoqi	10	2,500	10,236		12,736	0	0
Chang’an	23	8,658	34,626		43,284	2	0.046
Dalingshan and Songshanhu	17	3,997	18,196		22,193	2	0.090
Liaobu	20	5,854	25,908		31,762	28	0.881
Dalang	22	6,396	27,394		33,790	29	0.858
Changping	25	7,034	29,363		36,397	32	0.879
Dongkeng	9	3,511	11,914		15,425	10	0.648
Hengli	9	4,492	13,481		17,973	16	0.890
Shipai	12	3,405	11,916		15,321	15	0.979
Qishi	9	2,359	9,828		12,187	2	0.164
Qiaotou	6	952	12,808		13,760	10	0.727
Xiegang	5	1,439	6,186		7,625	2	0.262
Huangjiang	10	2,698	11,586		14,284	4	0.280
Qingxi	14	4,609	16,223		20,832	8	0.384
Fenggang	23	6,021	24,303		30,324	23	0.758
Zhangmutou	9	2,397	11,971		14,368	1	0.070
Wanjiang	20	995	4,274		5,269	0	0
Total	406	113,125	364,502		477,627	257	0.538

PEx, pectus excavatum.