Table 2.
Multiple Regression Models of Cross-Sectional Associations between Practice Quality and Practice Emergency Admission Rates for All Short-Term, Hyperglycemic, and Hypoglycemic Emergency Admissions
| All Short Term | Acute Hyperglycemic | Nonspecific Hyperglycemic | Hypoglycemic | |||||
|---|---|---|---|---|---|---|---|---|
| Coefficient† | Z-Statistic | Coefficient | Z-Statistic | Coefficient | Z-Statistic | Coefficient | Z-Statistic | |
| Cross-sectional model† | ||||||||
| Glycated hemoglobin (HbA1c) ≤7.4/7.5 | 0.985 | −8.33** | 0.981 | −6.92** | 0.986 | −6.21** | 0.996 | −1.40 |
| 7.4/7.5<HbA1c ≤10 | 0.987 | −6.32** | 0.981 | −5.64** | 0.988 | −4.35** | 0.997 | −0.67 |
| HbA1c monitored | 1.011 | 5.10** | 1.015 | 4.20** | 1.010 | 3.64** | 1.005 | 1.33 |
| Excluded from HbA1c monitoring | 1.000 | 0.15 | 1.001 | 0.29 | 1.000 | 0.04 | 0.997 | −0.69 |
| Year: 2005/2006‡ | 1.057 | 5.67** | 1.097 | 5.77** | 1.018 | 1.32 | 1.050 | 2.30* |
| Year: 2006/2007‡ | 1.074 | 5.80** | 1.182 | 8.46** | 0.975 | −1.53 | 1.048 | 1.94 |
| Diabetes prevalence | 1.073 | 7.83** | 1.089 | 5.98** | 1.067 | 5.44** | 1.062 | 3.93** |
| Baseline admission rate§ | 1.163 | 23.12** | 1.202 | 20.55** | 1.112 | 13.68** | 1.054 | 5.48** |
| Efron's R2¶ | 0.206 | 0.147 | 0.124 | 0.083 | ||||
Statistically significant at 5% level.
Statistically significant at 1% level.
Coefficients reported as incident rate ratios. Quality indicators measured as percentages. Prevalence and baseline admission rate measured in standard deviation units. The percentage change in the admission rate associated with a 1 unit change in a continuous explanatory variable, holding all other variables constant, can be calculated as (coefficient—1)100%. The coefficients on the year dummy variables show the difference in admissions in the year compared with 2004/2005, holding all other factors constant.
Compared with baseline year (2004/2005).
Baseline admission rate for short-term diabetic complications of same type as dependent variable, averaged over to 2001/2002 to 2003/2004.
Obtained from the R2 from a regression of actual admission rates on predicted admission rates.
+ All models also include a full set of covariates, including Primary Care Trust dummies and the proportions of the practice admissions at each hospital trust. Full results in Appendix Table SA3. The number of observations in each model is 24,035.