Table 4

Regression results for main specification and sensitivity analyses based on population achievement rates

Model descriptionAdmissions for bipolar disorderAdmissions for SMI
MH4MH5MH6MH9
NIRR95% CIIRR95% CINIRR95% CIIRR95% CI
Main analysis37 0371.169(1.011 to 1.353)1.106(1.012 to 1.209)38 7741.018(0.941 to 1.100)1.209(1.104 to 1.324)
Sensitivity analyses
Separate inclusion of indicators37 0371.235(1.079 to 1.413)1.141(1.051 to 1.240)38 7741.110(1.038 to 1.188)1.223(1.131 to 1.323)
Patient admitted at least once37 0371.108(0.966 to 1.272)1.116(1.028 to 1.212)38 7741.012(0.944 to 1.084)1.254(1.155 to 1.362)
Only emergency admissions37 0371.091(0.936 to 1.271)1.115(1.014 to 1.226)38 7740.986(0.908 to 1.071)1.249(1.132 to 1.379)
Achievement lagged by 1 year29 0301.095(0.941 to 1.273)0.958(0.872 to 1.053)30 6040.998(0.932 to 1.069)1.184(1.088 to 1.289)
Achievement lagged by 2 years21 2410.982(0.819 to 1.178)1.005(0.899 to 1.124)22 6751.074(0.994 to 1.161)1.047(0.948 to 1.155)
Achievement lagged by 3 years13 8630.865(0.698 to 1.071)0.940(0.822 to 1.076)15 0591.005(0.917 to 1.102)1.219(1.079 to 1.377)
Cross-sectional (year=2006)72391.119(0.825 to 1.519)1.055(0.856 to 1.299)76051.096(0.969 to 1.240)1.342(1.123 to 1.602)
Cross-sectional (year=2007)75261.027(0.758 to 1.392)1.099(0.913 to 1.323)78800.989(0.861 to 1.137)1.342(1.124 to 1.602)
Cross-sectional (year=2008)74410.999(0.720 to 1.386)0.935(0.768 to 1.139)77500.990(0.858 to 1.141)1.230(1.030 to 1.468)
Cross-sectional (year=2009)73431.024(0.694 to 1.510)0.986(0.802 to 1.214)76911.096(0.937 to 1.283)1.024(0.854 to 1.227)
Cross-sectional (year=2010)74481.179(0.803 to 1.731)1.006(0.816 to 1.240)78480.956(0.814 to 1.123)1.193(0.996 to 1.429)
Modelling exception rate separately37 0371.281(1.043 to 1.574)1.076(0.959 to 1.207)38 7740.988(0.907 to 1.076)1.055(0.931 to 1.195)
Interaction with exception rate: low (1st tercile)1.014(0.937 to 1.097)1.166(1.054 to 1.291)
Interaction with exception rate: medium (2nd tercile)1.013(0.934 to 1.098)1.158(1.041 to 1.287)
Interaction with exception rate: high (3rd tercile)0.987(0.902 to 1.081)1.149(1.018 to 1.297)
Within practice variation only (GP fixed effects)32 3281.241(1.066 to 1.446)1.209(1.101 to 1.329)37 8181.048(0.942 to 1.166)1.163(1.038 to 1.304)
  • All associations are expressed as IRRs.

  • IRR, incidence rate ratio; N, number of practice-year observations; SMI; serious mental illness.