Sensitivity, specificity, predictive values, κ value and percentage agreement between the questionnaire responses and observations related to poisonings
| Practice | Sensitivity (95% CI) | Specificity (95% CI) | PPV (95% CI) | NPV (95% CI) | κ Value (95% CI) | % Agreement (95% CI) |
|---|---|---|---|---|---|---|
| All medicines stored safely* [23] | 83.8 (72.9 to 91.6) | 31.0 (20.5 to 43.1) | 53.8 (43.8 to 63.5) | 66.7† (48.2 to 82.0) | 0.15 (0.01 to 0.28) | 56.8 (48.2 to 65.2) |
| All household products stored safely* [18] | 75.9 (56.5 to 89.7) | 60.9 (51.3 to 69.8) | 32.8 (21.8 to 45.4) | 90.9† (82.2 to 96.3) | 0.25 (0.11 to 0.38) | 63.9 (55.5 to 71.7) |
| All medicines and household products stored safely * [22] | 68.8 (41.3 to 89.0) | 68.5 (59.6 to 76.6) | 22.0 (11.5 to 36.0) | 94.4† (87.5 to 98.2) | 0.19 (0.05 to 0.34) | 68.6 (60.2 to 76.1) |
| All medicines stored in locked cupboard, cabinet, drawer or fridge [5] | 0 (0 to 70.8) | 87.7 (81.4 to 92.4) | 0 (0 to 17.6) | 97.8† (93.8 to 99.5) | −0.03 (−0.07 to 0.00) | 86.0 (79.6 to 91.0) |
| All household products stored in locked cupboard, cabinet, drawer or fridge [8] | 54.5 (23.4 to 83.3) | 79.0 (71.4 to 85.4) | 16.7 (6.4 to 32.8) | 95.8† (90.4 to 98.6) | 0.16 (0.00 to 0.33) | 77.3 (69.8 to 83.6) |
| All medicines and household products stored in locked cupboard, cabinet, drawer or fridge [3] | Unable to calculate due to frequencies of 0 in some cells | 92.5 (87.2 to 96.0) | ||||
| All medicines stored at adult eye level or above [27] | 78.1 (66.0 to 87.5) | 42.3 (30.6 to 54.6) | 54.9 (44.2 to 65.4) | 68.2† (52.4 to 81.4) | 0.20 (0.05 to 0.35) | 59.3 (50.5 to .67.6) |
| All household products stored at adult eye level or above [22] | 90.0 (55.5 to 99.7) | 88.5 (81.7 to 93.4) | 37.5 (18.8 to 59.4) | 99.1† (95.3 to 100) | 0.48 (0.27 to 0.69) | 88.6 (82.1 to 93.3) |
| All medicines and household products stored at adult eye level or above [18] | 80.0 (28.4 to 99.5) | 87.1 (80.3 to 92.1) | 18.2 (5.2 to 40.3) | 99.2† (95.5 to 100) | 0.25 (0.04 to 0.47) | 86.8 (80.2 to 91.9) |
| All medicines have child resistant caps or blister packs [1] | 93.3 (86.7 to 97.3) | 17.9 (8.9 to 30.4) | 68.1‡ (59.8 to 75.6) | 58.8 (32.9 to 81.6) | 0.13 (0.00 to 0.27) | 67.1 (59.2 to 74.3) |
| Any medicines been put in a container different from the one they came in [1] | 33.3 (7.5 to 70.1) | 98.0 (94.3 to 99.6) | 50.0 (11.8 to 88.2) | 96.1† (91.8 to 98.6) | 0.37 (0.05 to 0.69) | 94.4 (89.7 to 97.4) |
| All medicines kept in a locked medicine box [1] | 50.0 (6.8 to 93.2) | 82.8 (76.0 to 88.4) | 6.9 (0.8 to 22.8) | 98.5† (94.6 to 99.8) | 0.08 (−0.06 to 0.22) | 82.0 (75.2 to 87.6) |
| Medicines kept in fridge [1] | 61.1 (43.5 to 76.9) | 91.2 (84.8 to 95.5) | 66.7 (48.2 to 82.0) | 89.1† (82.3 to 93.9) | 0.54 (0.38 to 0.70) | 84.5 (77.9 to 89.7) |
| All household products have child-resistant caps [1] | 71.9 (58.5 to 83.0) | 35.6 (26.4 to 45.6) | 38.0 (28.8 to 47.8) | 69.8† (55.7 to 81.7) | 0.06 (−0.06 to 0.19) | 48.5 (40.5 to 56.4) |
| Any household products put in container different from the one they came in [0] | 6.3 (0.2 to 30.2) | 97.9 (94.1 to 99.6) | 25.0 (0.6 to 80.6) | 90.5† (84.8 to 94.6) | 0.06 (−0.12 to 0.24) | 88.9 (83.0 to 93.3) |
| Safety catch/lock on fridge§ [1] | 100 (2.5 to 100) | 67.7 (48.6 to 83.3) | 9.1 (0.2 to 41.3) | 100† (83.9 to 100) | 0.12 (−0.10 to 0.33) | 68.8 (50.0 to 83.9) |
[ ] missing values.
*Considered safe if stored at adult eye level (or above) or in drawers and cupboards with catches or locks, or if none stored in the house.
§Question only asked of people reporting storing medicines in fridge (n=33).
†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).