Table 4. Odds of injury associated with exposure and reaction to warning systems among surveyed cases (N = 98) and controls (N = 200).
| Warning characteristics | Case(N = 98) N (%) | Control (N = 200) N (%) | Odds Ratio (95% CI) | Adjusted Odds Ratio (95% CI)a |
| Warning System b,c | ||||
| AM/FM radio | 46 (46.9) | 103 (51.5) | 0.85 (0.52–1.38) | 0.81 (0.47–1.40) |
| NOAA Weather Radio | 17 (17.3) | 60 (60.3) | 0.51 (0.28–0.94) | 0.40 (0.19–0.84) |
| TV | 63 (64.3) | 158 (79.0) | 0.51 (0.30–0.88) | 0.45 (0.24–0.83) |
| Internet | 7 (7.1) | 53 (26.5) | 0.22 (0.10–0.50) | 0.20 (0.09–0.49) |
| Community | 43 (43.9) | 112 (56.0) | 0.64 (0.39–1.05) | 0.71 (0.42–1.17) |
| Sirens | 49 (50.0) | 131 (65.5) | 0.54 (0.32–0.89) | 0.50 (0.30–0.85) |
| No exposure to any | 23 (23.5) | 35 (17.5) | 1.74 (0.95–3.18) | 1.39 (0.69–2.78) |
| Frequency of Annual Siren Exposure | ||||
| 1–5 times | 37 (37.8) | 81 (40.5) | 0.50 (0.25–0.97) | 0.44 (0.19–1.02) |
| >5 times | 26 (26.5) | 78 (39.0) | 0.36 (0.18–0.74) | 0.41 (0.17–0.99) |
| Never | 24 (24.5) | 26 (13.0) | 1 [Reference] | 1 (Reference) |
| Unknown | 11 (11.2) | 15 (7.5) | ||
| Past Tornado Exposure after Hearing Sirens | ||||
| No | 53 (54.1) | 77 (38.5) | 1 [Reference] | 1 (Reference) |
| Yes | 30 (30.6) | 101 (50.5) | 0.43 (0.25–0.74) | 0.50 (0.28–0.90) |
| Unknown | 15 (15.3) | 22 (11.0) | ||
| Reaction to Siren on April 27, 2011 b,c,d | ||||
| Tried to get to shelter | 20 (20.4) | 61 (30.5) | 0.79 (0.41–1.51) | 0.92 (0.46–1.80) |
| Sought information | 37 (37.8) | 112 (56.0) | 0.43 (0.19–0.94) | 0.41 (0.18–0.93) |
| Got in car to flee | 4 (4.1) | 26 (13.0) | 0.34 (0.08–1.08) | 0.28 (0.05–1.01) |
| No location | 23 (23.5) | 47 (23.5) | 1.45 (0.75–2.80) | 1.39 (0.69–2.78) |
a
Each warning system controlled for access to respective system, age, sex and race; frequency of annual siren exposure adjusted for age, sex, race, and past tornado exposure after hearing sirens; past tornado exposure after hearing sirens adjusted for age, sex, race, and the frequency of annual siren exposure; reaction to siren on April 27, 2011 adjusted for age, sex and race.
b
Reference category is answer “no” to respective item.
c
Multiple positive responses allowed.
d
Calculations restricted to individuals who were exposed to sirens that day (N = 49 cases and N = 131 controls).