Table 3.

Multiple Regression Models of Longitudinal 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
Longitudinal model‡
Glycated hemoglobin (HbA1c) ≤7.4/7.5	0.991	−3.74**	0.989	−2.92**	0.991	−2.78**	0.999	−0.20
7.4/7.5<HbA1c ≤10	0.992	−3.08**	0.990	−2.30*	0.991	−2.45**	0.998	−0.37
HbA1c monitored	1.008	2.9**	1.006	1.40	1.011	2.97**	1.002	0.27
HbA1c excluded	0.999	−0.39	0.999	−0.14	0.999	−0.3	0.994	−0.920
Year: 2005§	1.058	4.52**	1.126	6.15**	0.996	−0.01	1.060	2.39*
Year: 2006§	1.066	3.30**	1.237	7.31**	0.931	−2.43**	1.041	0.253
Diabetes prevalence	1.074	4.52**	1.087	2.94**	1.104	3.13**	1.001	0.04
Efron's R2¶	0.359		0.315		0.204		0.086

^*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 measure 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 binary variables show the difference in admissions in the year compared with 2004/2005 holding all other factors constant.

^‡The longitudinal models include the same time-varying explanatory variables as the cross-sectional models.

^§Compared with baseline year (2004/2005).

^¶Obtained from the R² from a regression of actual admission rates on predicted admission rates.