Table 1.
| Characteristic | Missing data, n (%) | Observed value | Imputed value |
|---|---|---|---|
| Age | 48 (10.96)c | ||
| Male, n (%) | 525 400 (49) | ||
| Ethnicity, n (%) | 499 346 (46.8) | ||
| White | 304 533 (28.5) | ||
| Indian | 17 401 (1.63) | ||
| Pakistani | 7090 (0.66) | ||
| Bangladeshi | 1866 (0.17) | ||
| Other Indian | 8581 (0.80) | ||
| Black Caribbean | 4706 (0.44) | ||
| Black African | 12 316 (1.15) | ||
| Chinese | 3933 (0.37) | ||
| Other ethnic group | 207 882 (19.5) | ||
| Smoking status, n (%) | 45 091 (4) | ||
| Non-smoker | 604 889 (57) | ||
| Ex-smoker | 212 865 (20) | ||
| Current smoker | 204 809 (19) | ||
| Townsend index | 55 370 (5) | −0.92 (3.84)c | −0.91 (3.85)c |
| Body mass index | 156 686 (15) | 26.37 (5.19)c | 26.37 (5.19)c |
| Systolic blood pressure | 93 989 (9) | 125.46 (14.69)c | 125.42 (14.68)c |
| Diastolic blood pressure | 94 080 (9) | 77.01 (9.44)c | 77.01 (9.43)c |
| Total cholesterol | 581 011 (54) | 5.29 (0.98)c | 5.17 (0.98)c |
| HDL cholesterol | 632 782 (59) | 1.47 (0.44)c | 1.45 (0.43)c |
| Family history CVD, n (%) | 5214 (0.15%) | ||
| Family history diabetes, n (%) | 9288 (0.87%) | ||
| Atrial fibrillation, n (%) | 1626 (0.15%) | ||
| Rheumatoid arthritis, n (%) | 7330 (0.69%) | ||
| Chronic kidney disease, n (%) | 5366 (0.50%) | ||
| Taking corticosteroids, n (%) | 115 186 (11%) |
a
Population aged 30–74 years, without CVD, diabetes, or prescriptions for antihypertensives or statins in THIN database (total dataset for 2013: 1 067 654).
b
For diagnoses and other categorical variables, the absence of a clinical code is taken to mean the condition is absent.
c
Mean (standard deviation). CVD = cardiovascular disease. THIN = The Health Improvement Network.