Table 3 Risk factors associated with blood transfusion after total knee revision

≤ 50

Ref

——

——

51–60

0.994

0.920–1.074

0.888

61–70

1.082

1.002–1.168

0.043

≥ 71

1.490

1.377–1.613

<0.001

Female

1.254

1.209–1.302

<0.001

Race

White

Ref

——

——

Black

1.449

1.373–1.529

<0.001

Hispanic

1.380

1.281–1.486

<0.001

Asian or Pacific Islander

1.282

1.058–1.552

0.011

Native American

1.040

0.818–1.321

0.751

Other

1.066

0.995–1.143

0.068

Elixhauser score

0

Ref

——

——

1

1.212

1.111–1.323

<0.001

≥ 2

2.293

2.124–2.475

<0.001

Type of insurance

Medicare

Ref

——

——

Medicaid

0.996

0.916–1.083

0.925

Private insurance

0.834

0.795–0.875

<0.001

Self-pay

0.929

0.730–1.181

0.548

No charge

1.407

0.750–2.641

0.288

Other

0.691

0.625–0.764

<0.001

Bed size of hospital

Small

Ref

——

——

Medium

1.110

1.054–1.168

<0.001

Large

1.162

1.111–1.217

<0.001

Elective admission

0.511

0.491–0.532

<0.001

Teaching hospital

0.810

0.778–0.842

<0.001

Urban hospital

0.895

0.836–0.958

= 0.001

Region of hospital

Northeast

Ref

——

——

Midwest or North Central

0.625

0.591–0.661

<0.001

South

0.866

0.825–0.909

<0.001

West

0.718

0.677–0.761

<0.001