Assessment

Period

Cohort

M

SD

National Norm M

t

p

January 2020

470.49

50.04

552.5

−39.47

<0.001

August 2020

475.67

52.31

557.5

−37.68

<0.001

January 2021

486.78

54.24

590.5

−42.91

<0.001

May 2021

495.64

55.57

616.0

−56.91

<0.001

August 2021

491.64

56.63

616.0

−55.19

<0.001