TABLE 3

Multivariable negative binomial regression model for upper and lower respiratory tract infection (RTI) hospitalisations

CharacteristicUpper RTIsLower RTIs
ARR (95% CI)p-valueARR (95% CI)p-value
Time (per year)1.018 (1.015–1.020)1.066 (1.059–1.072)
Smoke-free legislation1.019 (1.005–1.032)0.0050.862 (0.844–0.880)<0.001
Time since smoke-free legislation (per year)0.981 (0.977–0.985)<0.0011.002 (0.994–1.009)0.701
Month
 JanuaryRef.Ref.
 February1.053 (1.037–1.069)0.801 (0.783–0.820)
 March1.094 (1.077–1.110)0.713 (0.696–0.730)
 April0.851 (0.838–0.865)0.538 (0.525–0.551)
 May0.860 (0.846–0.873)0.463 (0.451–0.475)
 June0.728 (0.716–0.740)0.358 (0.348–0.367)
 July0.770 (0.758–0.783)0.370 (0.360–0.380)
 August0.513 (0.505–0.522)0.222 (0.216–0.229)
 September0.663 (0.652–0.674)0.336 (0.327–0.345)
 October0.987 (0.972–1.002)0.597 (0.583–0.612)
 November1.098 (1.082–1.115)1.038 (1.015–1.061)
 December1.311 (1.292–1.331)1.584 (1.550–1.618)
Sex
 FemaleRef.Ref.
 Male1.311 (1.303–1.320)1.219 (1.207–1.232)
Age
 0–4 yearsRef.Ref.
 5–9 years0.135 (0.134–0.136)0.130 (0.128–0.131)
 10–14 years0.056 (0.055–0.056)0.057 (0.056–0.058)
Region
 Greater LondonRef.Ref.
 East Midlands2.226 (2.192–2.261)1.412 (1.378–1.447)
 East of England1.739 (1.712–1.766)1.203 (1.175–1.233)
 North East3.081 (3.032–3.131)1.816 (1.770–1.862)
 North West2.985 (2.942–3.029)1.564 (1.528–1.602)
 South East2.079 (2.048–2.110)1.385 (1.353–1.417)
 South West1.940 (1.910–1.971)1.447 (1.413–1.482)
 West Midlands2.466 (2.429–2.504)1.462 (1.427–1.497)
 Yorkshire and the Humber2.456 (2.419–2.493)1.631 (1.593–1.670)
Urbanisation level
 RuralRef.Ref.
 Urban1.030 (1.022–1.038)0.959 (0.947–0.972)
Index of Multiple Deprivation 
 Quintile 1#Ref. Ref.
 Quintile 21.099 (1.087–1.110)1.061 (1.044–1.078)
 Quintile 31.227 (1.215–1.240)1.166 (1.147–1.185)
 Quintile 41.356 (1.341–1.370)1.280 (1.259–1.302)
 Quintile 51.523 (1.507–1.540)1.418 (1.392–1.444)
  • ARR: admission rate ratio. #: least deprived; : most deprived.