Table 2. Characteristics of English and Danish study populations as of 1 March 2020.
| Characteristic | England*N=16 439 645n (%) | DenmarkN=4 491 336n (%) | |
| Age category | 18–40 years | 5 908 145 (35.9) | 1 600 989 (35.7) |
| 41–60 years | 5 390 450 (32.8) | 1 543 305 (34.4) | |
| 61–80 years | 4 094 795 (24.9) | 1 145 112 (25.5) | |
| >80 years | 1 046 255 (6.4) | 201 930 (4.5) | |
| Sex | Female | 8 330 335 (50.7) | 2 209 312 (49.1) |
| Male | 8 109 310 (49.3) | 2 282 024 (50.8) | |
| Deprivation† | 1 (most deprived) | 3 230 685 (19.7) | 864 398 (19.3) |
| 2 | 3 297 365 (20.1) | 903 277 (20.1) | |
| 3 | 3 570 705 (21.7) | 906 819 (20.2) | |
| 4 | 3 324 625 (20.2) | 908 303 (20.2) | |
| 5 (least deprived) | 3 016 270 (18.3) | 908 539 (20.2) | |
| Rural-urban | Rural | 3 513 405 (21.4) | – |
| Urban | 12 926 245 (78.6) | – | |
| Diabetes mellitus¶ | 1 309 600 (7.9) | 292 027 (6.5) | |
| Asthma‡ | 1 439 760 (8.8) | 619 136 (13.8) | |
| COPD§ | 533 645 (3.2) | 417 649 (9.3) |
*
England data is rounded to the nearest 5.
†
Deprivation measured by Index of Multiple Deprivation in England and income in Denmark.
‡
Asthma definition: England: aAsthma code in primary care record in the 3 years prior to study entry, Denmark: hHospital diagnosis code or asthma medication prescribing.
§
COPD definition: England: aAge>40 with COPD code in primary care record prior to study entry, Denmark: hHospital diagnosis code, or COPD medication prescribing.
¶
Diabetes definition: Type 1 or type 22 diabetes mellitus code in primary care record prior to study entry, Denmark: hHospital diagnosis code or diabetes medication prescribing.
COPDchronic obstructive pulmonary disease