TABLE 3.
Summary statistics for weather factors significantly associated with the count of generic Escherichia coli in the univariable negative binomial hurdle models in Table 4a
| Factor and variableb | Value for: |
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|---|---|---|---|---|---|---|---|---|---|
| Total spinach samples (n = 955) |
Positive E. coli counts (n = 63) |
Zero E. coli counts (n = 892) |
|||||||
| Mean | Median | Range | Mean | Median | Range | Mean | Median | Range | |
| Temp (°C) | |||||||||
| tm2 | 17.3 | 17.0 | 2.7–25.7 | 16.4 | 16.3 | 2.7–24.2 | 17.3 | 17.1 | 2.7–25.7 |
| tmd6 | 17.1 | 16.7 | 3.5–22.8 | 16.3 | 15.9 | 3.5–20.6 | 17.1 | 16.8 | 3.5–22.8 |
| tmd7 | 16.8 | 16.7 | 5.3–22.9 | 16.8 | 15.8 | 5.3–19.5 | 16.8 | 16.7 | 5.3–22.9 |
| tmd8 | 16.6 | 16.7 | 6.7–23.2 | 16.9 | 15.7 | 6.7–18.4 | 16.6 | 16.7 | 6.7–23.2 |
| tmd9 | 16.6 | 16.7 | 7.5–23.3 | 16.6 | 15.6 | 7.5–17.7 | 16.6 | 16.8 | 7.5–23.3 |
| tmd10 | 16.7 | 16.7 | 7.8–23.3 | 16.7 | 15.6 | 7.8–17.7 | 16.7 | 16.8 | 7.8–23.3 |
| tmd15 | 16.5 | 16.6 | 8.2–23.4 | 16.2 | 15.4 | 8.2–18.9 | 16.6 | 16.7 | 8.2–23.4 |
| tmd20 | 17.1 | 16.7 | 8.6–23.4 | 15.5 | 15.3 | 8.6–19.3 | 17.5 | 16.8 | 8.6–23.4 |
| tmd25 | 17.4 | 16.8 | 8.5–23.5 | 14.6 | 15.1 | 8.5–19.4 | 18.0 | 16.9 | 8.5–23.5 |
| tmd29 | 17.4 | 16.6 | 8.4–23.3 | 13.6 | 14.8 | 8.4–19.3 | 17.5 | 16.7 | 8.4–23.3 |
| ti2 | 10.0 | 9.6 | −8.4–22.0 | 7.5 | 9.2 | −8.4–22.0 | 10.0 | 9.7 | −8.4–22.0 |
| tid10 | 9.5 | 9.7 | 0.8–18.7 | 8.8 | 8.6 | 0.8–14.1 | 9.8 | 9.8 | 0.8–18.7 |
| tid15 | 9.9 | 9.5 | 1.0–19.1 | 7.8 | 8.4 | 1.0–13.5 | 10.1 | 9.6 | 1.0–19.1 |
| tx3 | 26.1 | 25.9 | 7.3–36.0 | 25.8 | 24.5 | 7.3–31.7 | 26.5 | 26.0 | 7.3–36.0 |
| txd3 | 25.8 | 25.6 | 16.5–34.3 | 25.5 | 24.9 | 16.5–30.7 | 26.0 | 25.7 | 16.5–34.3 |
| txd4 | 25.1 | 25.3 | 13.4–34.2 | 24.9 | 24.3 | 13.4–30.9 | 25.1 | 25.4 | 13.4–34.2 |
| txd5 | 25.2 | 25.0 | 11.2–34.3 | 25.1 | 23.9 | 11.2–31.0 | 25.4 | 25.1 | 11.2–34.3 |
| txd6 | 25.3 | 25.1 | 13.3–34.3 | 25.4 | 24.0 | 13.3–30.3 | 25.3 | 25.2 | 13.3–34.3 |
| txd7 | 24.9 | 25.1 | 15.0–33.9 | 25.7 | 24.0 | 15.0–28.9 | 24.9 | 25.2 | 15.0–33.9 |
| txd8 | 24.8 | 25.1 | 16.2–33.7 | 24.6 | 23.8 | 16.2–27.1 | 24.8 | 25.2 | 16.2–33.7 |
| txd9 | 24.9 | 25.1 | 15.7–33.7 | 24.9 | 23.7 | 16.7–26.9 | 24.9 | 25.2 | 15.7–33.7 |
| txd10 | 25.1 | 25.1 | 15.8–33.8 | 25.1 | 23.8 | 17.3–26.9 | 25.1 | 25.2 | 15.8–33.8 |
| txd15 | 24.7 | 25.0 | 16.5–33.8 | 24.7 | 23.8 | 17.5–28.0 | 24.7 | 25.1 | 16.5–33.8 |
| txd20 | 25.0 | 25.2 | 16.6–33.7 | 23.9 | 23.4 | 17.4–28.7 | 25.4 | 25.3 | 16.6–33.7 |
| txd25 | 24.9 | 25.2 | 16.7–33.9 | 23.4 | 23.1 | 16.7–28.9 | 25.7 | 25.3 | 16.7–33.9 |
| txd29 | 25.4 | 25.0 | 16.4–33.4 | 22.1 | 22.7 | 16.4–28.3 | 25.5 | 25.1 | 16.4–33.4 |
| Wind speed (m/s) | |||||||||
| ws2 | 3.0 | 3.6 | 1.3–8.7 | 3.1 | 3.6 | 1.8–8.7 | 3.0 | 3.6 | 1.3–8.7 |
| Precipitation (mm) | |||||||||
| pd1 | 0.0 | 0.6 | 0.0–6.0 | 0.0 | 0.1 | 0.0–4.4 | 0.0 | 0.6 | 0.0–6.0 |
| pd5 | 0.0 | 1.6 | 0.0–14.4 | 1.9 | 2.8 | 0.0–14.4 | 0.0 | 1.5 | 0.0–14.4 |
| pd6 | 0.1 | 1.5 | 0.0–13.2 | 2.0 | 2.5 | 0.0–13.2 | 0.1 | 1.4 | 0.0–13.2 |
| pd7 | 0.2 | 1.4 | 0.0–11.5 | 2.2 | 2.3 | 0.0–11.5 | 0.2 | 1.3 | 0.0–11.5 |
| pd8 | 0.1 | 1.3 | 0.0–10.2 | 2.0 | 2.1 | 0.0–10.2 | 0.1 | 1.2 | 0.0–10.2 |
| pd9 | 0.1 | 1.3 | 0.0–9.2 | 1.8 | 2.0 | 0.0–9.2 | 0.1 | 1.2 | 0.0–9.2 |
| pd10 | 0.3 | 1.3 | 0.0–8.4 | 1.6 | 1.9 | 0.0–8.4 | 0.3 | 1.2 | 0.0–8.4 |
| pd25 | 0.6 | 1.0 | 0.0–4.3 | 1.4 | 1.5 | 0.0–3.7 | 0.6 | 1.0 | 0.0–4.3 |
| pd29 | 0.6 | 1.0 | 0.0–3.8 | 1.7 | 1.7 | 0.0–3.2 | 0.6 | 1.0 | 0.0–3.8 |
Only variables with P values of <0.20 in Table 4 are shown.
tm2, average daily temperature on day 2 prior to sample collection (SC); tmdX, mean of the average daily temperatures (°C) in the period between the day of SC and day X prior to SC; ti2, minimum temperature on day 2 prior to SC; tidX, mean of the minimum daily temperatures (°C) between the day of SC and day X prior to SC; tx3, maximum daily temperature (°C) on day 3 prior to SC; txdX, mean of the maximum daily temperatures (°C) between the day of SC and day X prior to SC; ws2, wind speed on day 2 prior to SC; pdX, mean amount of rain (mm) between the day of SC and day X prior to SC.