Review Metadata

Once you've found a slide, check its detail page carefully before relying on it for teaching - the catalogue is built from a large, historical archive, and not every slide's metadata has been curated yet.

A slide's detail page has several sections:

• Metadata - organ, species, stain, and other descriptive information.
• Technical metadata - image dimensions, scanner information, and other file-level technical details.
• Expert contributor notes - commentary added by expert contributors (see About).
• Slide annotations - teacher and workflow annotations already attached to the slide, if any.

If something looks wrong - the wrong organ, an unclear stain, a missing description - use the Metadata corrections button on the slide's page. Pick the metadata area the issue relates to (Organ, Tissue, Species, Stain, Description, Notes, or a general comment), suggest a correction, and submit. If the correct term isn't in the list, you can describe a new one for an administrator to review and add to the dictionary.

Controlled vocabularies (dictionaries)

Organ, Tissue, Species, and Stain are all drawn from a fixed, curated list rather than free text - this is what keeps search working well: everyone using "Kidney" instead of a mix of "kidney" / "Kidneys" / "renal" means a search for one of them finds all of them. This is also why the correction form asks you to pick from the list rather than type anything - if the right term genuinely isn't there yet, describe it and an administrator will review and add it, rather than the catalogue quietly accumulating near-duplicate terms.

Organ and Tissue aren't just two independent lists - the database also records which tissues are recognised as belonging to which organ (e.g. Cortex and Medulla under Kidney), so this relationship can be used to sanity-check metadata rather than treating the two fields as unrelated. This relationship data isn't shown in the browser above; administrators can see it via the dictionary export on the Dictionaries admin page.

Comparison (CMP) slides

A small number of slides show two (or more) distinct specimens side by side in the same image, each prepared with a different stain, specifically so a viewer can compare what each stain reveals on the same tissue - an early, manual precursor to modern colocalisation techniques. These are marked with the CMP badge.

This is not the same as a slide with more than one stain applied to a single specimen (a "complex stain", e.g. a combined H&E and PAS technique on one piece of tissue) - that's a single specimen, not a comparison, and doesn't get the CMP badge. Telling the two apart requires actually looking at the image: there's nothing in a filename or scan metadata that reliably distinguishes "one specimen, two techniques" from "two specimens, two stains". This is genuinely expert-judgement-only - it is not, and will not be, automated.

A slide becomes CMP by its stain value matching a stain_dictionary entry marked Comparison slide. The existing convention for these entries spells out each specimen, e.g. a) H&E b) PAS or a) Masson b) H&E - administrators curate these on the Stain Dictionary sysadmin page. Once an entry is marked Comparison slide, every slide whose stain matches it - now or in the future - picks up the CMP badge automatically (immediately when a stain correction is applied, or via the "Sync comparison flags from stain dictionary" job on Maintenance Jobs for anything imported in bulk).

Roles in the review workflow

Reviewing and improving metadata is a shared effort across three roles:

• User - the default account role. Can search, review any slide's metadata, and submit a correction when something looks wrong, as described above. A user's own submissions go into a queue for a reviewer to check - a user can't approve their own or anyone else's corrections.
• Reviewer - can see every submitted correction and work through them: mark one as under review, then Approve or Reject it. Once an approved correction has actually been applied to the slide's metadata, the reviewer marks it "resolved" (thanking the contributor) to close the loop.
• Expert - can add Expert contributor notes directly to a slide's detail page. This is separate from the correction workflow above - it's additive commentary from someone with subject-matter authority, not a proposed fix to existing metadata.

Corrections move through a simple lifecycle: submitted → (optionally) marked under review → approved or rejected → resolved.

Once you're satisfied the metadata is accurate (or you've submitted a correction and are continuing anyway), move on to Clean Artefacts and Prepare Slides.