Table 2

Number of cases, person-years follow-up and rates of first recorded diagnosis of PDD (per 10,000 person-years) by year of diagnosis and year of birth (in two year categories). The diagonally linked numbers identify rates among children of the same age in different years

Year of first diagnosis



1992–93
 1994–95
 1996–97
 1998–99
 2000–01

Birthyear
 n
 PY
 rate
 n
 PY
 rate
 n
 PY
 rate
 n
 PY
 rate
 n
 PY
 rate

73–74
 5
 257638
 0.19
 5
 263712
 0.19
 1
 233838
 0.04
 4
 194554
 0.21
 4
 118997
 0.34
 age 26–28
75–76
 0
 233164
 0.00
 4
 232393
 0.17
 5
 208111
 0.24
 4
 175331
 0.23
 2
 107426
 0.19
 age 24–26
77–78
 5
 233093
 0.21
 2
 227191
 0.09
 7
 191785
 0.36
 8
 162057
 0.49
 0
 100419
 0.00
 age 22–24
79–80
 1
 265530
 0.04
 2
 257752
 0.08
 9
 211888
 0.42
 13
 171491
 0.76
 3
 104136
 0.29
 age 20–22
81–82
 6
 268477
 0.22
 3
 262006
 0.11
 6
 217307
 0.28
 20
 174989
 1.14
 10
 104093
 0.96
 age 18–20
83–84
 10
 275918
 0.36
 9
 270128
 0.33
 4
 226897
 0.18
 12
 184013
 0.65
 5
 110565
 0.45
 age 16–18
85–86
 14
 283299
 0.49
 11
 277108
 0.40
 21
 231591
 0.91
 28
 187229
 1.50
 12
 112080
 1.07
 age 14–16
87–88
 26
 294006
 0.88
 18
 285548
 0.63
 16
 237945
 0.67
 32
 191788
 1.67
 31
 114057
 2.72
 age 12–14
89–90
 42
 298297
 1.41
 45
 289890
 1.55
 30
 241271
 1.24
 48
 194806
 2.46
 41
 116246
 3.53
 age 10–12
91–92
 5
 248952
 0.2
 77
 285511
 2.70
 53
 238318
 2.22
 56
 192373
 2.91
 51
 114277
 4.46
 age 8–10
93–94
 0
 29342
9
 231555
 0.39
 70
 227807
 3.07
 89
 184757
 4.82
 67
 110641
 6.06
 age 6–8
95–96


0
 26360
13
 177284
 0.73
 98
 176267
 5.56
 69
 106292
 6.49
 age 4–6
97–98





0
 20351
11
 144307
 0.76
 81
 104606
 7.74
 age 2–4
99–00








0
 15479
4
 79129
 0.51
 age 0–2

Smeeth et al. BMC Medicine 2004 2:39   doi:10.1186/1741-7015-2-39