Table 4 Results of linear regression analysis

Gender (control = female)

 Male

0.124*

0.065

-1.905

0.057

-0.004

0.252

Age group (control = youth)

 Middle age

0.128

0.086

-1.478

0.139

-0.042

0.297

 Young elderly

0.572***

0.101

-5.657

< 0.001

0.373

0.770

 Elderly

1.156***

0.138

-8.346

< 0.001

0.884

1.427

 Long-lived elderly

3.138***

0.533

-5.893

< 0.001

2.094

4.182

Education level (control = elementary school and below)

 Junior high school

-0.038

0.081

-0.472

0.637

-0.196

0.120

 Secondary or high school

0.115

0.129

-0.890

0.373

-0.139

0.369

 College

-0.102

0.156

-0.655

0.512

-0.407

0.203

 Bachelor’s degree and above

0.176

0.189

-0.928

0.353

-0.195

0.547

Marital status (control = never married)

 Married

0.047

0.151

-0.314

0.753

-0.248

0.343

Source of admission (control = non-emergency sources)

 Emergency sources

-0.103

0.134

-0.772

0.440

-0.366

0.159

Mode of admission (control = walk)

 Stretcher

2.252***

0.193

-11.689

< 0.001

1.874

2.630

 Wheelchair

1.727***

0.145

-11.926

< 0.001

1.443

2.011

Purpose of visit (control = non-surgical)

 Surgical

0.294*

0.155

-1.9

0.057

-0.009

0.597

Occupation (control = farmer)

 Self-employed

-0.108

0.118

-0.914

0.361

-0.339

0.124

 Retired (resigned) person

-0.305

0.192

-1.586

0.113

-0.682

0.072

 Worker

-0.323**

0.162

-1.996

0.046

-0.640

-0.006

 Other

-0.115

0.100

-1.150

0.250

-0.310

0.081

Medical payment method (control = new rural cooperative medical insurance)

 Basic medical insurance for urban residents

0.070

0.080

-0.873

0.383

-0.087

0.227

 Basic medical insurance for urban workers

-0.012

0.125

-0.096

0.924

-0.257

0.233

 Fully self-paid

-0.085

0.176

-0.484

0.628

-0.430

0.260

 Other

0.231

0.340

-0.679

0.497

-0.436

0.898

Major diagnostic categories (control = diseases of the circulatory system)

 Certain infectious and parasitic diseases

-0.010

0.274

-0.036

0.971

-0.547

0.527

 Neoplasms

0.752***

0.13

5.785

< 0.001

0.497

1.007

 Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism

0.950***

0.357

2.663

0.008

0.250

1.649

 Endocrine, nutritional and metabolic diseases

-0.117

0.096

-1.213

0.225

-0.305

0.072

 Mental and behavioral disorders

0.207

0.315

0.657

0.511

-0.411

0.825

 Diseases of the nervous system

-0.042

0.139

-0.303

0.762

-0.314

0.230

 Diseases of the eye and adnexa

-0.259*

0.143

-1.813

0.070

-0.538

0.021

 Diseases of the ear and mastoid process

-0.500***

0.114

-4.376

< 0.001

-0.725

-0.276

 Diseases of the respiratory system

0.828***

0.209

3.955

< 0.001

0.417

1.238

 Diseases of the digestive system

0.570***

0.111

5.119

< 0.001

0.352

0.788

 Diseases of the skin and subcutaneous tissue

0.428**

0.214

1.997

0.046

0.008

0.849

 Diseases of the musculoskeletal system and connective tissue

0.936***

0.187

4.995

< 0.001

0.569

1.304

 Diseases of the genitourinary system

1.113***

0.164

6.801

< 0.001

0.792

1.434

 Congenital malformations, deformations and chromosomal abnormalities

0.719***

0.274

2.625

0.009

0.182

1.256

 Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified

0.047

0.309

0.154

0.878

-0.558

0.653

 Injury, poisoning and certain other consequences of external causes

0.615***

0.176

3.492

< 0.001

0.270

0.961

 Factors influencing health status and contact with health services

0.837***

0.147

5.71

< 0.001

0.550

1.125

 Intercepts

0.070

0.194

0.36

0.719

-0.310

-0.450