Moderator variables

Sample

size

(N = 9163)

Number of effect sizes

(k = 66)

Effect size and 95% confidence interval

Heterogeneity

Effect size (g)

Lower limit

Upper limit

p

I-squared, %

Q-statistic

p

Study Design

TGPPD

2746

32

0.858

0.524

1.911

<0.001

93.9

510.54

<0.001

TGPD

5023

25

0.467

0.259

0.638

<0.001

83.7

188.27

<0.001

Other

1394

9

0.174

−0.053

0.401

0.132

73.2

29.81

<0.001

Sample Size

1 - 60

888

19

0.668

0.267

1.07

0.001

87.3

141.94

<0.001

61 - 120

2224

27

0.724

0.467

0.982

<0.001

82.2

221.26

<0.001

Above 120

6051

20

0.455

0.213

0.698

<0.001

95.2

395.24

<0.001

Learning Stage

Primary school

112

1

2.132

1.665

2.599

<0.001

0

0

<0.001

Secondary school

597

8

0.745

0.404

1.085

<0.001

70.3

23.54

0.001

High school

165

2

0.384

−0.405

1.173

0.34

84.3

6.38

0.012

University

8289

55

0.586

0.415

0.757

<0.001

92.6

725.06

<0.001

Subject Area

Social science

3342

18

0.579

0.367

0.79

<0.001

87

130.64

<0.001

Natural science

2343

16

0.67

0.415

0.925

<0.001

86.5

111.01

<0.001

Medicine

2458

16

0.648

0.181

1.114

0.006

96.6

435.27

<0.001

Humanities

545

10

1.024

0.576

1.473

<0.001

82.9

52.27

<0.001

Engineering &Technology

475

6

−0.118

−0.551

0.315

0.593

81

26.28

<0.001

Knowledge Type

Conceptual knowledge

6848

45

0.621

0.464

0.778

<0.001

95.6

456.72

<0.001

Procedural knowledge

2315

21

0.696

0.266

1.127

0.002

87.6

357.73

<0.001

Instructor Equivalence

Same instructor

6859

53

0.72

0.527

0.913

<0.001

92.9

729.74

<0.001

Different instructor

1697

9

0.346

0.188

0.504

<0.001

51.4

16.46

0.036

Not available

607

4

0.11

−0.774

0.998

0.808

95.2

61.93

<0.001

Intervention Duration

1 - 5 weeks

590

7

0.632

0.205

1.059

0.004

84.1

44.08

<0.001

6 - 10 weeks

1291

14

1.199

0.544

1.854

<0.001

96.3

352.21

<0.001

Above 10 weeks

7282

45

0.441

0.297

0.584

<0.001

87.7

349.39

<0.001