Table 7.
Comparison of Johnston's ABCD2 derivation and validation groups with our study
| Johnston's ABCD2 derivation and validation group [14] | Hong Kong TIA study | |
|---|---|---|
| Study design | Retrospective but prospectively enrolled data from a computerized database | Retrospective but prospectively compulsory e-coded data from a computerized database and hard copies |
| Country | Oxford (UK) and California (USA) | Hong Kong |
| Year | 1998–2005 in the validation group | 2006 |
| Setting | ED cohort: multiple ED Clinic cohort | Multiple ED |
| TIA diagnosed by | ED cohort: ED physicians Clinic cohort: neurologists | Neurologists or internists |
| Age | 66–80% >60 years | 72.1% >60 years |
| Ethnicity | White 70–99% | Chinese 100% |
| Symptom onset on ED arrival or evaluation | 0–0 day and 0–3 days | 0–3 days (96%, 0–1 day) |
| Symptomatic on arrival | 50% of the California derivation group | 51.7% |
| How the ‘day of stroke’ was counted | From day of evaluation in the clinic or ED to day of stroke | From day of ED registration to day of stroke |
| Prior stroke | 0–20% | 19.9% |
| On antiplatelet on discharge | 81–99% in the validation group | 89% |
| On anticoagulation on discharge | 4–14% | 6.9% |