Table 3.
Results of the multivariate GAM for the presence of rats outside dwellings. Odds ratio (OR) and 95% confidence intervals are presented for the variables retained in the final model.
| Parametric coefficients | Odds Ratio | 95% Confidence Interval | p value |
|---|---|---|---|
| Litter (No) | — | <0.001 | |
| Litter (Yes) | 1.83 | 1.66–2.00 | |
| Number of dwellings in area (500+ ) | — | <0.001 | |
| Number of dwellings in area (300–499) | 1.08 | 0.90–1.31 | |
| Number of dwellings in area (100–299) | 0.86 | 0.73–1.01 | |
| Number of dwellings in area (50–99) | 0.93 | 0.79–1.10 | |
| Number of dwellings in area (25–49) | 1.09 | 0.90–1.30 | |
| Number of dwellings in area (Less than 25) | 1.41 | 1.16–1.72 | |
| Width of plot (Same as dwelling) | — | <0.001 | |
| Width of plot (less than 10 m) | 1.13 | 1.00–1.26 | |
| Width of plot (less than 20 m) | 1.21 | 1.07–1.37 | |
| Width of plot (20 m or more) | 1.50 | 1.26–1.78 | |
| Animals outside (No) | — | <0.001 | |
| Animals outside (Yes) | 2.77 | 2.48–3.10 | |
| Road type (Major trunk road or main road) | — | 0.007 | |
| Road type (Side road) | 0.82 | 0.73–0.93 | |
| Road type (Cul de sac/cresent) | 0.88 | 0.76–1.00 | |
| Road type (Private road) | 0.78 | 0.61–0.99 | |
| Road type (No road) | 1.09 | 0.84–1.42 | |
| Nature of area (City centre) | — | <0.001 | |
| Nature of area (Urban) | 1.11 | 0.80–1.54 | |
| Nature of area (Suburban residential) | 0.97 | 0.70–1.35 | |
| Nature of area (Rural residential) | 1.64 | 1.17–2.31 | |
| Nature of area (Village centre) | 2.07 | 1.44–2.97 | |
| Nature of area (Rural) | 3.24 | 2.24–4.69 | |
| Drainage system faults (No) | — | <0.001 | |
| Drainage system faults (Yes) | 1.73 | 1.43–2.10 | |
| Problems in area (No problems) | — | <0.001 | |
| Problems in area (Slight problems) | 1.35 | 1.19–1.54 | |
| Problems in area (Moderate problems) | 1.78 | 1.52–2.09 | |
| Problems in area (Substantial problems) | 2.65 | 2.21–3.18 | |
| Tenure type (Owner occupied) | — | <0.001 | |
| Tenure type (Private rented) | 0.98 | 0.86–1.12 | |
| Tenure type (Local authority) | 1.50 | 1.33–1.69 | |
| Tenure type (Housing association (RSL)) | 1.32 | 1.14–1.53 | |
| Date of construction (Pre 1850) | — | <0.001 | |
| Date of construction (1850–1899) | 0.71 | 0.58–0.88 | |
| Date of construction (1900–1918) | 0.84 | 0.67–1.04 | |
| Date of construction (1919–1944) | 0.75 | 0.62–0.92 | |
| Date of construction (1945–1964) | 0.52 | 0.43–0.64 | |
| Date of construction (1965–1980) | 0.51 | 0.41–0.63 | |
| Date of construction (Post 1980) | 0.53 | 0.43–0.66 | |
| Region (East Midlands) | — | <0.001 | |
| Region (Eastern) | 0.95 | 0.79–1.14 | |
| Region (London) | 1.00 | 0.82–1.22 | |
| Region (North East) | 0.96 | 0.77–1.19 | |
| Region (North West & Merseyside) | 0.84 | 0.70–1.01 | |
| Region (South East) | 1.00 | 0.84–1.19 | |
| Region (South West) | 1.02 | 0.85–1.23 | |
| Region (West Midlands) | 1.77 | 1.50–2.10 | |
| Region (Yorkshire & Humberside) | 1.05 | 0.88–1.25 |
The p-value refers to the Chi-square test for analysis of deviance (model with factor included compared to model without the factor). The variables month of survey and type of dwellings were not retained in the final model. The smoothed term year had an approximate significance of p < 0.001 but OR for this non-linear term are not presented.