Exposures and reporting periods, response options and categorisation of responses
| Exposures reported 24 h prior to injury (cases) or 24 h prior to completing questionnaire (controls) | Response option | |
|---|---|---|
| Safety gates | ||
| a. Used anywhere in the home | Yes/no | |
| b. Used on stairs | Yes/no | Grouped into: closed stair gate/gate left open/no gate |
| c. Left stair gate open | Yes/no | |
| Stair features | ||
| a. Landing part-way up | Yes/no | |
| b. Spiral stairs or winding stair cases | Yes/no | |
| c. Handrails on stairs | On all stairs/on some stairs/no | |
| d. Banister/railing on stairs | On all stairs/on some stairs/no Grouped into: on all stairs vs other responses | |
| e. Banister/railing: width of biggest gap | Inches Grouped into: tertiles | |
| f. Stair covering | Carpet/wood/metal/concrete/lino/vinyl/don't know/other Grouped into: carpet vs other responses | |
| g. Stairs are too steep | Agree/neither agree or disagree/disagree | |
| h. Stairs are too narrow | Agree/neither agree or disagree/disagree | |
| i. Stairs are poorly lit | Agree/neither agree or disagree/disagree | |
| j. Steps are in need of repair | Agree/neither agree or disagree/disagree | |
| k. Banister/handrail is in need of repair | Agree/neither agree or disagree/disagree | |
| l. Stair covering is in need of repair | Agree/neither agree or disagree/disagree | |
| m. Stairs are safe to use | Agree/neither agree or disagree/disagree Grouped into: agree vs other responses A composite stair safety variable (for use as a confounder in analyses) included items (g) to (m) grouped as: No safe responses: agree to all of items (g) to (l) and disagree to (m) All safe responses: disagree to all items (g) to (l) and agree to item (m) Some safe responses: all other combinations of responses | |
| Use of baby walkers (ages 0–36 months only) | Yes/no | |
| Use of playpens or travel cots while child awake (ages 0–36 months only) | Yes/no | |
| Use of stationary activity centres (ages 0–36 months only) | Yes/no | |
| Exposures reported for 1 week prior to injury (cases) or 1 week prior to completing questionnaire (controls) | Response option | |
| Tripping hazards on stairs | Every day/most days/some days/never/does not apply Grouped into: at least some days vs never | |
| Exposures ever reported prior to injury (cases) or prior to completing questionnaire (controls) | Response option | |
| Taught child safety rules or instructions about | ||
| a. How to behave when going down the stairs | Yes/no | |
| b. Carrying big/lots of things while going down the stairs | Yes/no | |
| c. Leaving things on stairs | Yes/no | |