Sensitivity, specificity, predictive values, κ value and percentage agreement between the questionnaire responses and observations related to scalds
| Practice | Sensitivity (95% CI) | Specificity (95% CI) | PPV (95% CI) | NPV (95% CI) | κ Value (95% CI) | % Agreement |
|---|---|---|---|---|---|---|
| Has cordless kettle or curly flex [2] | 82.1 (75.1 to 87.7) | 75.0 (19.4 to 99.4) | 99.2‡ (95.8 to 100) | 9.7 (2.0 to 25.8) | 0.13 (−0.02 to 0.28) | 81.9 (75.0 to 87.5) |
| Kettle kept at back of kitchen surface [1] | 94.2 (88.4 to 97.6) | 42.5 (27.0 to 59.1) | 83.2‡ (75.9 to 89.0) | 70.8 (48.9 to 87.4) | 0.42 (0.26 to 0.59) | 81.4 (74.5 to 87.1) |
| Safety gate across kitchen doorway [0] | 79.4 (62.1 to 91.3) | 85.2 (77.8 to 90.8) | 58.7 (43.2 to 73.0) | 94.0† (88.0 to 97.5) | 0.57 (0.43 to 0.72) | 84.0 (77.4 to 89.2) |
[ ] missing values.
†A higher proportion of respondents over-reported than under-reported safe practice (NPV exceeds PPV).
‡A higher proportion of respondents under-reported than over-reported safe practice (PPV exceeds NPV).