Table 4.

Observed monthly mortality rates and predicted mortality rates based on the aggregated county data

Panel A: The aggregated monthly mortality rates of 22 counties
	Predicted mortality Rate (‰) (95% CI)	Observed mortality rate (‰)	Standardized predicted errors
January 2003	3.28 (2.11–4.45)	3.56	0.48
February 2003	3.04 (1.87–4.20)	2.86	-0.30
March 2003	3.01 (1.84–4.17)	2.09	-1.58
April 2003	2.79 (1.62–3.96)	2.45	-0.58
May 2003	3.39 (2.22–4.55)	2.97	-0.71
June 2003	3.54 (2.37–4.71)	3.45	-0.15
July 2003	3.23 (2.06–4.40)	2.24	-1.70
August 2003	2.86 (1.69–4.03)	2.70	-0.28
September 2003	3.28 (2.11–4.45)	2.60	-1.18
October 2003	2.97 (1.80–4.14)	2.98	0.01
November 2003	2.93 (1.76–4.10)	2.89	-0.07
December 2003	2.66 (1.49–3.83)	2.24	-0.72
Panel B: The aggregated mortality rate of 12 counties where contain hospitals with more than 1,000 beds
January 2003	3.04 (1.86–4.23)	3.31	0.45
February 2003	2.85 (1.67–4.03)	3.12	0.46
March 2003	2.95 (1.77–4.14)	2.14	-1.39
April 2003	2.70 (1.52–3.88)	2.41	-0.48
May 2003	3.34 (2.16–4.53)	3.25	-0.16
June 2003	3.70 (2.52–4.89)	3.13	-0.98
July 2003	3.25 (2.06–4.43)	1.82	-2.42
August 2003	2.98 (1.80–4.16)	2.50	-0.81
September 2003	3.26 (2.07–4.44)	2.43	-1.41
October 2003	2.98 (1.79–4.16)	2.64	-0.58
November 2003	2.87 (1.69–4.06)	2.42	-0.77
December 2003	2.55 (1.37–3.73)	1.97	-0.98