No of playgrounds | Odds ratio* | 95% CI |
---|---|---|
*Calculations with “conditional logistic regression” (SAS: PROC PHREG) with matching variable age and sex (170 cases and 168 controls). Baseline category: number of playgrounds >3. | ||
0 | 1.8 | 0.9 to 3.5 |
1–3 | 1.4 | 0.7 to 2.5 |
>3 | 1.0 | — |