Effects* | edf† | Parameter estimate | Standard error | p value‡ |
---|---|---|---|---|
Parametric terms | ||||
Smokefree | ||||
Before§ | ||||
After | −0.050 | 0.022 | 0.03 | |
Region | ||||
North East§ | ||||
North West | 0.050 | 0.022 | 0.02 | |
Yorkshire and Humber | 0.035 | 0.023 | 0.13 | |
East Midlands | −0.12 | 0.024 | <0.001 | |
West Midlands | 0.051 | 0.023 | 0.02 | |
East of England | −0.28 | 0.024 | <0.001 | |
London | −0.079 | 0.023 | <0.001 | |
South East | −0.31 | 0.023 | <0.001 | |
South West | −0.22 | 0.024 | <0.001 | |
Smooth terms | ||||
Influenza | 3.58 | <0.001 | ||
Temperature | 5.53 | 0.006 | ||
Month | 7.71 | <0.001 | ||
Region×year | ||||
North East | 1.00 | 0.008 | ||
North West | 6.17 | <0.001 | ||
Yorkshire and Humber | 2.28 | 0.21 | ||
East Midlands | 2.79 | 0.06 | ||
West Midlands | 2.82 | 0.32 | ||
East of England | 1.00 | 0.03 | ||
London | 5.56 | <0.001 | ||
South East | 3.67 | <0.001 | ||
South West | 4.30 | <0.001 |
*AR(1) term=0.22.
†edf, the effective degrees of freedom for the smooth term is a measure of the complexity of the estimated smooth term. For example, the edf for each region in the Region×Year effect represents the degree of non-linearity of the long-term trend in that region. If edf=1, the shape of the relationship between the smooth term and the outcome is linear. Values of edf increase progressively with the addition of more non-linear relationships.
‡p value from a t test on parametric regression coefficients and F test on smooth terms. p Values for smooth terms test the null hypothesis that there is no relationship between the smooth term and emergency admissions for asthma.
§Baseline category.