Table 6 Estimated IRT parameter values for the 9QSF combination with the NRM for the developmental group

Item

Gender

IRT Parameters Values without Accounting for DIF

a_i(11)

a_i(12)

a_i(13)

a_i(21)

a_i(22)

a_i(23)

a_i(31)

a_i(32)

a_i(33)

c_i(11)

c_i(12)

c_i(13)

c_i(21)

c_i(22)

c_i(23)

c_i(31)

c_i(32)

c_i(33)

1

All

2.817

4.147

5.575

5.899

8.204

10.329

5.391

17.461

18.590

1.396

2.056

2.074

1.429

1.602

1.745

1.839

1.828

1.792

2

All

2.817

5.102

8.882

4.095

7.303

8.797

11.209

11.209^a

12.589

0.896

1.713

1.710

1.180

1.499

1.630

1.730

1.730^a

1.702

3

All

0.726

1.471

1.227

1.318

2.100

1.355

2.267

2.794

2.394

2.657

3.758

4.077

2.369

2.335

3.199

2.822

2.746

2.124

4

All

1.806

6.653

12.413

3.545

11.530

8.426

16.246

21.364

20.098

1.866

2.001

1.963

1.727

1.856

1.891

1.953

2.086

1.960

5

All

1.264

-0.987

2.110

1.584

1.757

1.573

1.237

1.879

2.199

2.214

-6.726

2.724

2.152

2.829

3.351

4.594

4.082

2.535

6

All

1.543

3.078

0.661

2.215

4.392

3.194

3.097

3.373

6.390

2.070

2.444

9.259

2.111

2.035

2.568

2.329

2.426

2.050

7

All

1.457

3.504

3.640

2.947

4.583

6.095

5.375

5.761

6.831

1.485

2.449

2.412

1.630

1.832

2.254

2.170

1.992

1.974

8

All

1.544

4.594

4.594^a

2.213

3.027

4.682

3.270

2.832

5.722

1.711

2.335

2.335^a

1.844

2.109

2.130

2.396

2.649

2.047

9

All

3.006

22.604

22.604^a

3.784

5.533

8.547

7.059

5.426

7.316

2.164

2.644

2.644^a

2.212

2.294

2.348

2.157

2.377

2.225

Item

Gender

IRT Parameters Values Accounting for DIF

a_i(11)

a_i(12)

a_i(13)

a_i(21)

a_i(22)

a_i(23)

a_i(31)

a_i(32)

a_i(33)

c_i(11)

c_i(12)

c_i(13)

c_i(21)

c_i(22)

c_i(23)

c_i(31)

c_i(32)

c_i(33)

1

M

1.877

3.535^a

4.823^a

7.482

7.182

9.688

2.965

16.850

18.626

1.850

2.170^a

2.177^a

1.544

1.763

1.720

2.242

1.887

1.942

F

1.877

3.535

4.823

4.416

7.203

6.588

8.015

10.973

12.933

1.680

2.170

2.177

1.498

1.636

2.001

1.854

1.845

1.751

2

M

1.877

5.161^a

8.094^a

3.785

6.309

5.527

11.454

11.454^a

15.614

1.305

1.747

1.730^a

1.354^a

1.929

1.753

1.989

1.989^a

2.071

F

1.877

5.161

8.094

2.835

6.749

9.965

11.361

11.361^a

11.784

1.014

1.747

1.730

1.376

1.536

1.746

1.774

1.774^a

1.703

3

All

0.770

1.500

1.292

1.402

2.153

1.443

2.194

2.290

3.057

2.531

3.705

3.913

2.282

2.307

3.059

2.787

2.458

2.009

4

M

1.877

7.178

10.268^a

4.539

10.076^a

6.696

12.374^a

17.574

10.240

1.941

2.006

1.921^a

1.650

1.797^a

1.851

1.895^a

2.262

1.909

F

1.877

6.386

10.268

3.231

10.076

9.269

12.374

17.574^a

15.687

1.803

2.005

1.921

1.776

1.797

1.927

1.895

2.262^a

1.943

5

M

1.877

-0.121

2.490

2.534

1.595

1.163

2.794

2.218^a

2.045

1.758

-46.399

2.394

1.939

2.513

3.596

2.283

3.409^a

2.399

F

1.877

-4.018

2.619

1.651

3.144

3.148

-3.384

2.218

3.146

1.726

-3.104

2.392

1.955

2.292

2.454

-3.221

3.409

2.185

6

All

1.523

3.194

0.821

2.319

4.138

2.853

3.147

3.791

6.204

2.101

2.412

7.557

2.077

2.056

2.710

2.319

2.334

2.063

7

M

1.877

4.159^a

4.698

5.225

5.786

6.666^a

6.649

6.759

13.936

1.312

2.150^a

1.856

1.469

1.815

2.085^a

1.921

1.818

2.223

F

1.877

4.159

4.698^a

2.834

5.097

6.666

7.160

7.134

7.604

1.283

2.150

1.856^a

1.603

1.708

2.085

2.077

1.923

1.865

8

M

1.877

4.798^a

4.798^a

2.925

1.882

7.366

9.494

6.674

10.526

1.440

2.200^a

2.200^a

1.560

2.912

1.744

1.996

1.967

1.972

F

1.877

4.798

4.798^a

2.384

3.708

7.366^a

2.877

2.164

6.045

1.582

2.200

2.200^a

1.796

1.920

1.744^a

2.486

3.105

2.003

9

M

1.877

11.826^a

11.826^a

4.163

4.929^a

9.665

9.195

4.550^a

18.334

2.759

2.517^a

2.517^a

2.101

2.328^a

2.181

2.062

2.454^a

2.390

F

1.877

11.826

11.826^a

3.119

4.929

9.665^a

5.990

4.550

3.777

2.684

2.517

2.517^a

2.439

2.328

2.181^a

2.337

2.454

2.591