Table 2

Intraclass correlations (ICC) and measures of bias for selected continuous and ordinal variables.





Difference between ratings





Variable (units) (Item Number)
N*
ICC
(95% LCL)
Mean
SD
P

Age (years) (1.1)
104
0.98
(0.96)
-0.11
3.19
0.957
Stroke onset time (mins) (6.2) §
19
0.99
(0.99)
-10.00
29.72
0.903
ED arrival time (mins) (4.1)
78
0.87
(0.82)
16.55
168.07
0.775
Time first seen by doctor (mins) (4.2)
49
0.88
(0.82)
22.14
160.26
0.770
Initial brain imaging time (mins) (5.2)
30
0.93
(0.89)
-19.97
111.67
0.809
Total Cholesterol (mg/dL) (12.9)
35
0.91
(0.86)
4.29
22.03
0.705
HDL (mg/dL) (12.9)
33
0.99
(0.99)
0.33
1.34
0.916
LDL (mg/dL) (12.9)
28
1.00

0.00
0.00
1.000
Modified Rankin at discharge (Score) (12.6)
99
0.80
(0.73)
-0.01
1.10
0.968

*Where both prototype and audit data have values. †Calculated as audit abstractor minus hospital abstractor. ‡Standard deviation of the difference. §Where both auditor and prototype raters recorded onset time as specific. 95% LCL = 95% Lower Confidence Limit. P = T-test probability.

Reeves et al. BMC Neurology 2008 8:19   doi:10.1186/1471-2377-8-19