Both item-level and test-level analyses indicate the MAP Growth measurement scales are remaining stable¶

Claim · All claims
Evidence · 1 study · design r2 · q2
Currency · newest study 2022 · checked against its sources 2026-10-20 (automated, 1 of 1 entry) · not reviewed by a person · overdue for a recheck since 2025: tool and model accuracy changes quickly

Subclaims¶

q2 i? Despite 4.2–6.9% of items being flagged, the item-level and test-level analysis results indicate that the MAP Growth measurement scales are remaining stable, consistent with past studies such as Kingsbury (2003). → He 2022

Evidence¶

He 2022¶

He, W. (2022). MAP Growth item parameter drift study. NWEA Research Report. https://www.nwea.org/research/publication/map-growth-item-parameter-drift-study/

q2 · i? · design · r2

Conclusion drawn in the report's Conclusion and Discussion section from the full sequence of analyses: re-estimation showing negligible average difficulty change, Robust Z flagging, and rescoring showing negligible average score impact. The report adds that both old and new calibration procedures yield comparable parameter estimates.

"Nevertheless, both the item-level and test-level analysis results indicate that the MAP Growth measurement scales are remaining stable. This conclusion is consistent with what past studies (e.g., Kingsbury, 2003) have found."

Discussion¶

Related Claims¶

• Rescoring with new item parameters changed average ability estimates negligibly, with new and original scores correlated above 0.99 — a narrower finding that bears on this claim
• Flagged items showed no clear pattern by original difficulty, spreading across the entire scale like unflagged items — related
• Average drift in MAP Growth item difficulty estimates is negligible across subjects, with original-new correlations above 0.99 — a narrower finding that bears on this claim
• 13%–15% of MAP Growth items per subject were flagged as significantly drifted by the Robust Z procedure, with no clear pattern among flagged items — related
• The 2020 norms report states the MAP Growth scale remains stable while status patterns shifted relative to the 2015 norms — possibly the same claim (merge candidate)
• Robust Z procedure flagged between 4.2% and 6.9% of MAP Growth items as unstable across subjects — possibly the same claim (merge candidate)
• Students encountered substantial numbers of items with changed parameter estimates, averaging 11–38% of test length by subject — related