The 16-item CT–PCK Survey shows internal consistency reliability around .71–.72 and person separation reliability of .69¶

Claim · All claims
Evidence · 1 study · design r3 · q2
Currency · newest study 2026 · not yet checked against its sources · not reviewed by a person · recheck by 2029: tool and model accuracy changes quickly

Subclaims¶

q2 i? Internal consistency coefficients (KR-20 and Cronbach's alpha of .71, McDonald's omega of .72) and Rasch person separation reliability (.69) support the 16-item survey as a consistent single-construct measure. → Witherspoon 2026

Evidence¶

Witherspoon 2026¶

Witherspoon, E.B.; Dracopoli, M., Hawkins, M., Dahlke, K. (2026). Developing a measure of middle school math teachers' pedagogical content knowledge of computational thinking (REL 2026–007). U.S. Department of Education, Institute of Education Sciences, National Center for Education Evaluation and Regional Assistance. https://ies.ed.gov/use-work/resource-library/report/descriptive-study/developing-measure-middle-school-math-teachers-pedagogical-content-knowledge-computational-thinking

q2 · i? · design · r3

Reliability analysis of the 16-item survey using pooled responses from 102 teachers. KR-20 and Cronbach's alpha were .71 and McDonald's omega .72; Rasch person separation reliability was .69, which the report characterizes as adequate for distinguishing ability levels.

"Overall internal consistency reliability for the survey showed a Kuder-Richardson Formula 20 (KR-20) coefficient and a Cronbach's alpha of .71, and a McDonald's omega of .72"

Discussion¶

Related Claims¶

• The 16-item CT–PCK Survey measures CT pedagogical content knowledge for math as a single overall construct — a broader claim this one bears on
• Content experts and practitioner reviews supported the content and face validity of the CT–PCK Survey — related
• Teachers scored across a wide range on the CT–PCK Survey, averaging about 61 percent correct, with 92 percent scoring above chance — related
• The overall CT–PCK Survey functioned similarly across teacher characteristic groups, though some items showed raw differential item functioning above 0.64 logits — related
• The post-study survey instrument showed high internal consistency (alpha = 0.90) — related
• Questionnaire constructs showed acceptable to strong internal consistency (α = 0.740 to 0.945) — related
• A pilot study (N = 10) established timed-administration parameters, showing high internal consistency and minimal speededness for the SCS1 12-item subset — related
• CTAT shows robust psychometric properties for higher education CS/AI students, with reliable internal consistency and adequate IRT item parameters — related
• A high Cronbach's alpha across items measuring distinct knowledge aspects indicates the test is not working as intended — related
• FFT scores showed acceptable-to-good internal consistency, with the overall PPR score more internally consistent than any single domain score — related