Accuracy of IBD case identification information streams
| Data source | True positives n / % | False positives n / % | % of total true positives identified |
| Pathology coding | 7661 (99) | 81 (1) | 73 |
| ICD-10 code K50/51 | 5525 (75) | 1186 (25) | 53 |
| Mesalazine prescribing | 5079 (84) | 956 (16) | 48 |
| ICD-10 code K50/51/52 | 4254 (27) | 11 625 (73) | 40 |
| Secondary care prescribing | 842 (100) | 0 | 8 |
| Paediatric registry | 122 (100) | 0 | 1 |
| Total unique cases | 10 499 | 14 102 |
All true positive, live Lothian or non-Lothian resident IBD cases identified from manual case review of ‘possible’ cases were used to derive the accuracy of each information stream. The proportion of cases accepted as true positive (ie, IBD) or false positive (ie, non-IBD) for each information stream is presented, in addition to the proportion of all true positives.