Table 7 Mean (± SD) change scores for youth self-reported outcomes (CIS-S) by STEM program quality level (DoS—overall score)

STEM attitudes

M

SD

M

SD

M

SD

χ² (2)

p

d

[95% CI]

d

[95% CI]

d

[95% CI]

d

[95% CI]

d

[95% CI]

 STEM engagement

7.71^a

14.90

8.76^a,b

13.96

11.20^b

15.85

11.81

0.003

0.23

[0.07, 0.38]

n.s.

0.06

[− 0.10,0.21]

n.s.

n.s.

 STEM career interest

7.32^a

17.42

8.61^a,b

15.35

11.51^b

17.18

16.18

< 0.001

0.24

[0.08, 0.40]

n.s.

0.09

[− 0.06,0.25]

0.30

[0.15,0.44]

0.19

[0.02,0.36]

 STEM career knowledge

7.54^a

14.65

10.56^b

14.51

13.56^c

15.96

25.04

< 0.001

0.39

[0.23, 0.55]

0.12

[− 0.02,0.26]

0.21

[0.06,0.37]

0.45

[0.31,0.60]

0.25

[0.08,0.42]

 STEM activity participation

8.47

12.86

8.45

12.65

9.94

14.42

2.56

0.278

n.s.

n.s.

n.s.

n.s.

n.s.

 STEM identity

5.08^a

13.56

7.61^b

12.32

11.01^c

14.79

32.38

< 0.001

0.42

[0.26, 0.58]

0.18

[0.04,0.32]

0.27

[0.11,0.42]

0.39

[0.25,0.54]

0.27

[0.10,0.44]

 Critical thinking

7.69^a

15.30

8.71^a,b

14.96

11.49^b

16.55

12.26

0.002

0.24

[0.08, 0.40]

n.s.

0.11

[− 0.04,0.26]

0.20

[0.06,0.35]

n.s.

 Perseverance

6.75^a

15.03

7.97^a

14.95

11.51^b

16.61

16.86

< 0.001

0.30

[0.14, 0.46]

0.16

[0.02,0.30]

0.13

[− 0.02,0.28]

n.s.

n.s.

 Relationships with adults

4.93^a

13.99

7.42^a,b

14.21

9.71^b

15.40

17.18

< 0.001

0.32

[0.16, 0.48]

0.18

[0.04,0.32]

0.13

[− 0.02,0.28]

n.s.

n.s.

 Relationships with peers

3.48^a

12.96

5.35^a,b

12.24

7.53^b

15.22

12.06

0.002

0.28

[0.13, 0.44]

n.s.

0.13

[− 0.02,0.28]

0.27

[0.12,0.41]

n.s.