Table.
Results of incremental search strategies for detecting cases of ischaemic heart disease in 11 practices
| Search strategy | Sensitivity (%) (95% CI) (n=93) | No (%) of patients with marker (n=1680) | Positive predictive value (%) (95% CI) | Yield* | No of patients not identified (No of practices) |
|---|---|---|---|---|---|
| With G3 Read code | |||||
| G3 | 47 (36 to 59) | 53 (3.2) | 83 (70 to 96) | 1 in 1.2 | 49 (11) |
| G3 or nitrate | 73 (59 to 87) | 86 (5.1) | 79 (71 to 87) | 1 in 1.2 | 25 (10) |
| G3 or nitrate or aspirin | 89 (83 to 96) | 182 (10.8) | 46 (35 to 56) | 1 in 2.1 | 10 (7) |
| G3 or nitrate or aspirin or atenolol | 94 (87 to 100) | 239 (14.2) | 36 (27 to 46) | 1 in 2.8 | 6 (4) |
| G3 or nitrate or aspirin or atenolol or digoxin or statin | 96 (89 to 100) | 271 (16.1) | 33 (23 to 42) | 1 in 3 | 4 (2) |
| Without G3 Read code | |||||
| Nitrate | 47 (36 to 59) | 53 (3.2) | 83 (70 to 96) | 1 in 1.2 | 49 (11) |
| Nitrate or aspirin | 82 (76 to 87) | 171 (10.2) | 44 (34 to 55) | 1 in 2.2 | 17 (8) |
| Nitrate or aspirin or atenolol | 87 (79 to 96) | 229 (13.6) | 35 (28 to 43) | 1 in 2.8 | 12 (5) |
| Nitrate or aspirin or atenolol or statin or digoxin | 89 (81 to 98) | 261 (15.5) | 32 (26 to 38) | 1 in 3.1 | 10 (4) |
*
100/positive predictive value.