Table 1

Characteristics of patients with at least one encounter for heart failure between January 1, 2004 and December 31, 2005 stratified by their participation in the study derivation and validation sets.

Variable

Total Population

(n = 4,174)

Derivation sample

(n = 300)

Validation sample (n = 100)

Unselected patients (n = 3,774)

P-value*


Age (years) -- mean ± SD

67 ± 14

67 ± 14

68 ± 14

67 ± 14

0.47


Male -- no.(%)

2011 (48%)

155 (52%)

46 (46%)

1810 (48%)

0.42


White -- no. (%)

2615 (63%)

61%

59%

63%

0.12


Hypertension -- no. (%)

3384 (81%)

244 (81%)

77 (77%)

3063 (81%)

0.57


Diabetes -- no. (%)

1409 (34%)

104 (35%)

31 (31%)

1274 (34%)

0.80


Chronic obstructive pulmonary disease - no. (%)

600 (14%)

46 (15%)

12 (12%)

542 (14%)

0.71


Coronary Atherosclerosis - no. (%)

829 (20%)

42 (14%)

15 (15%)

772 (20%)

0.012


≥1 BNP measurement during the study period - no. (%)

2374 (57%)

170 (57%)

53 (53%)

2151 (57%)

0.73


Maximum BNP level - median (interquartile range)

198

(88-494)

192

(84-500)

144

(90-379)

201

(89-500)

0.634


SD denotes standard deviation

*P-value for the comparison across patients in the derivation set, patients in the validation set, and patients not used in the analysis.

Alqaisi et al. BMC Health Services Research 2009 9:237   doi:10.1186/1472-6963-9-237

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