Table 4

Characteristics of included population, excluded population, and total population in Taiwan 2001–2003.
Characteristics
 Included population
 Excluded population
 Total population

N
 %
 N
 %
 N
 %
Total
 396,049
 100
 325,240
 100
 721,289
 100
Gender of infant





     Male
 206,723
 52.2
 170,385
 52.4
 377,108
 52.3
     Female
 189,326
 47.8
 154,524
 47.6
 343,850
 47.7
Maternal age





     <20 years
 15,217
 3.8
 16,223
 5.0
 31,440
 4.4
     20–34
 341,307
 86.2
 282,381
 86.8
 623,688
 86.5
     35-
 39,519
 10.0
 26,631
 8.2
 66,150
 9.2
Maternal diabetes mellitus





     Yes
 930
 0.2
 876
 0.3
 1,806
 0.3
     No
 395,119
 99.8
 324,364
 99.7
 719,483
 99.7
Plurality





     Singleton
 385,371
 97.3
 316,903
 97.4
 702,274
 97.4
     Multiple birth
 10,678
 2.7
 8,337
 2.6
 19,015
 2.6
Population density (no of people/km2)*





     <1000
 83,357
 21.1
 94,304
 29.5
 177,661
 24.8
     1000–5000
 153,654
 38.8
 144,069
 45.0
 297,723
 41.6
     >5000
 158,674
 40.1
 81,817
 25.6
 240,491
 33.6

Hwang et al. Environmental Health 2008 7:23   doi:10.1186/1476-069X-7-23