From: Development of an algorithm for determining smoking status and behaviour over the life course from UK electronic primary care records
WHS
Totals
GP
Missing data
smoker
Ex-smoker
Never smoker
<5
99
120
199
423
Smoker
16
1017
452
236
1721
22
112
1108
126
1368
29
73
501
2721
3324
72
1301
2181
3282
6836