Table 5

Result of difference-in-differences analysis showing the change in COPD emergency admissions per 100 000 population in Knowsley following the intervention relative to the control group, 2005–2016

CoefficientLower 95% CIUpper 95% CIP value
Treatment (Knowsley=1; control=0)37.99−14.3990.370.155
Period (postintervention=1; preintervention=0)−20.03−
DiD estimator (treatment*period)−24.10−58.7910.590.173
  • Model based on equation shown in online supplementary file and includes random intercept for LSOA, and fixed effects for per cent of population aged 50+ years, per cent female, per cent unemployed and two spline terms for time (full model results are given in online supplementary file).

  • Model based on 98 Knowsley and 392 control LSOAs, and 5880 observations.

  • COPD, chronic obstructive pulmonary disease; DiD, difference-in-differences; LSOA, lower-layer super output area.