  The introduction of computing education into curricula worldwide requires
multi-year assessments to evaluate the long-term impact on learning. However,
no single Computational Thinking (CT) assessment spans primary school, and no
group of CT assessments provides a means of transitioning between instruments.
This study therefore investigated whether the competent CT test (cCTt) could
evaluate learning reliably from grades 3 to 6 (ages 7-11) using data from 2709
students. The psychometric analysis employed Classical Test Theory, Item
Response Theory, Measurement Invariance analyses which include Differential
Item Functioning, normalised z-scoring, and PISA's methodology to establish
proficiency levels. The findings indicate that the cCTt is valid, reliable and
gender-fair for grades 3-6, although more complex items would be beneficial for
grades 5-6. Grade-specific proficiency levels are provided to help tailor
interventions, with a normalised scoring system to compare students across and
between grades, and help establish transitions between instruments. To improve
the utility of CT assessments among researchers, educators and practitioners,
the findings emphasise the importance of i) developing and validating
gender-fair, grade-specific, instruments aligned with students' cognitive
maturation, and providing ii) proficiency levels, and iii) equivalency scales
to transition between assessments. To conclude, the study provides insight into
the design of longitudinal developmentally appropriate assessments and
interventions.
