Table 3.
Scenarios of agreement in the validation of self-reported stroke
| Scenario | Prevalence (self-report) | Prevalence (hospital-recorded) | Sensitivity | Positive predictive value | Kappa (95% CI) | Prevalence index |
|---|---|---|---|---|---|---|
| 1921-26 cohort | ||||||
| A* | 6.6% | 2.1% | 78.1% | 24.5% | 0.35 (0.25 to 0.46) | 0.91 |
| B † | 6.6% | 3.1% | 86.0% | 41.2% | 0.54 (0.44 to 0.63) | 0.90 |
| C ‡ | 6.6% | 3.4% | 86.8% | 45.1% | 0.57 (0.48 to 0.67) | 0.90 |
| D | 6.6% | 4.0% | 88.7% | 53.9% | 0.65 (0.57 to 0.74) | 0.89 |
| 1946-52 cohort | ||||||
| A* | 1.2% | 0.7% | 78.6% | 44.0% | 0.56 (0.37 to 0.75) | 0.98 |
| B † | 1.2% | 0.7% | 80.0% | 48.0% | 0.60 (0.42 to 0.78) | 0.98 |
*Scenario A: Agreement between self-reported and hospital-recorded stroke.
†Scenario B: Hospital comparison group includes TIA and sequelae of cerebrovascular disease diagnoses, and hospital–recorded strokes occurring before the period of interest.
‡Scenario C: Compares self-reported stroke with any hospital-recorded cerebrovascular disease.
§Scenario D: Scenario C, plus includes women as having had a possible stroke if they provided comments on the stroke event in the questionnaire.