Table 3 Nasopharyngeal Carcinoma Survival Rate and Adjusted Hazard Ratios by Physician Caseload Groups and the Characteristics of the Patients and Providers (n = 1225)

Physician characteristics

   Physician volume

Low (3-17)

1

Medium (17-53)

0.884

0.70-1.16

0.884

High (54-130)

0.60

0.45-0.78

< 0.001

   Physician age

≦40 years

1

41-50 years

1.22

0.97-1.52

0.086

≥51 years

0.78

0.59-1.02

0.073

Hospital characteristics

   Hospital ownership

Public

1

Non-for-profit

1.11

0.87-1.42

0.414

For-profit

0.94

0.65-1.36

0.746

   Hospital level

Medical center

1

Regional hospital

0.88

0.68-1.16

0.368

District hospital

1.25

0.77-2.03

0.376

Patient characteristics

   Patient gender

Female

1

Male

0.93

0.75-1.15

0.509

   Patient age

35-44 years

1

45-54 years

1.15

0.89-1.49

0.277

55-64 years

1.10

0.83-1.45

0.507

65-74 years

1.12

0.81-1.56

0.488

≧ 75 years

0.88

0.48-1.51

0.675

   Charlson Comorbidity Index score

< 4

1

≧4

1.28

1.04-1.56

0.018

   Treatment modality

Radiotherapy

1

Chemoradiotherapy

1.03

0.82-1.29

0.784

   Geographic location

North

1

Central

1.18

0.90-1.55

0.242

Southern and Eastern

1.30

1.00-1.70

0.051

   Enrollee category

EC 1-2

1

EC 3

1.35

0.71-2.55

0.358

EC 4

1.04

0.86-1.26

0.698