What Is a Medical Chronology? Definition, Fields and How to Prepare One

A medical chronology is the dated index of a person's medical records that lawyers, nurse consultants and claims teams build before they argue anything about the case. Hathr.AI builds cited chronologies from full productions, and the product page for that work is AI medical record review on Hathr.AI. This page covers the definition, the fields, the preparation steps and the mistakes that get a chronology impeached.

Key takeaways

• A medical chronology lists every dated medical event in a case, one row per event per source document, with a page citation on each row.
• A chronology records facts. Causation theory and criticism of care belong in a separate memo that cites the chronology by row number.
• The standard seven columns miss the failures that matter in litigation: onset conflicts, treatment gaps, illegible sources and supplemental productions.
• Hathr.AI reads scanned and handwritten pages with OCR, holds up to 100,000 pages per account, and drafts chronologies with page citations inside a FedRAMP High authorization boundary.
• Our free 12-field template adds the columns that catch those failures, and you can copy it into a spreadsheet today.

What is a medical chronology?

A medical chronology is a table of every medical encounter in a person's records, sorted by date of service, with the provider, the findings, the treatment and the source page for each entry. Personal injury, medical malpractice, workers' compensation, disability and life care planning work all start from one.

Searchers also call it a medical record chronology, a medical records chronology, a legal medical chronology or a med chron. All four name the same document. A legal medical chronology differs only in its audience: it is built to survive cross-examination, so every row must point at a produced page.

What goes in a medical chronology?

A medical chronology contains seven standard fields: date of service, provider, facility, presenting complaint, objective findings, assessment and treatment plan. Litigation chronologies need five more fields, and the source citation holds the rest up.

The full schema with a worked excerpt is in our medical chronology template. In that excerpt, an emergency department record dates neck pain to the evening of the collision, and a handwritten orthopedic intake three weeks later records onset as "approx. 2 wks ago". The template captures the conflict, flags the handwriting for verification and computes a 22-day gap against a 7-day follow-up instruction. A seven-column template shows none of the three.

How do you prepare a medical chronology?

You prepare a medical chronology in seven steps: collect, de-duplicate, sort, extract, cite, flag and verify. The order matters, because citing after extraction instead of during it is the most common reason a chronology needs a second pass.

1. Collect every production. Log each file with its custodian and date received. Missing providers show up later as treatment gaps, so note them now.
2. Remove duplicates. Productions repeat pages across custodians. Keep one copy and record where the duplicates came from.
3. Sort by date of service. Use the encounter date, not the dictation or signature date. Mixed date formats cause most out-of-order chronologies.
4. Extract one row per event per source. Quote findings verbatim where you can. "Severe, unremitting pain" and "pain" are different exhibits.
5. Cite as you extract. Add the page reference in the same pass. A row without a citation is a note, and notes do not survive deposition.
6. Flag legibility, conflicts and gaps. Mark handwritten and faxed sources, link contradicting rows, and compute days between encounters.
7. Verify the flagged rows by eye. Read the partial and illegible entries against the page. Leave the clean rows to spot checks.

Steps 4 through 6 take most of the hours on a production of several thousand pages, and they are the steps software now does well. Run steps 3 through 6 on one of your own productions in Hathr.AI, free for 7 days, then do step 7 yourself.

Medical chronology vs medical summary vs narrative report

A medical chronology indexes events by date. A medical summary condenses the records into prose organized by condition or body part. A narrative report argues a position, such as causation or a deviation from the standard of care.

• Chronology: factual, tabular, cited per row. Every other document cites it.
• Summary: factual, prose, organized by issue. Useful for demand letters and adjuster reviews.
• Narrative report: opinion, signed by a qualified reviewer. Belongs to the expert, not the index.

Keep them separate. We hold firm on this: a chronology that contains argument becomes attackable as advocacy, and once opposing counsel shows one slanted row, every row is in play.

Who prepares a medical chronology?

Paralegals, legal nurse consultants, medical record review companies and AI tools prepare medical chronologies, and many firms combine two of them. The question that decides the split is how many pages you receive each month and how many questions each case generates after the first draft.

If you are choosing between those options, our guide to medical record review for law firms compares them on cost, security and follow-up questions, and our AI medical chronology software guide covers the software purchase in detail.

Can AI prepare a medical chronology?

AI can prepare a medical chronology draft with a page citation on every row, and the reviewer then verifies the flagged entries. Three checks separate a usable AI chronology from a fluent one: OCR on handwritten and faxed pages, page-level citations, and the ability to question the whole production in one workspace.

Hathr.AI covers all three. Its OCR includes handwriting recognition. Each account holds up to 100 documents totaling up to 100,000 pages, so an onset date on page 40 and a contradiction on page 9,000 sit in the same workspace. Retrieval-augmented generation grounds each answer in your documents and returns the page, so you can ask for a citation on every row.

The records stay protected while you do it. Hathr.AI runs Anthropic's Claude inside AWS GovCloud under a FedRAMP High authorization boundary, includes a signed BAA on every web app account, and never trains on customer data.

Frequently asked questions

What is a medical chronology in a personal injury case?

A medical chronology in a personal injury case is a date-ordered table of every treatment event after the injury, and relevant events before it, with a page citation on each row. Attorneys use it to value the claim, find pre-existing conditions and treatment gaps, and prepare depositions.

How is a medical chronology different from a medical summary?

A medical chronology sorts events by date in a table, one row per event per source. A medical summary condenses the same records into prose by condition or issue. Most cases need the chronology first, because the summary and any expert report cite it.

How do you evaluate the quality of a medical chronology service?

Check three things on a sample from your own worst production: a page citation on every row, flags on illegible or handwritten sources instead of silent guesses, and correct detection of conflicting dates across providers. Ask the vendor in writing where the records are processed and whether a BAA covers them.

Can I use ChatGPT to make a medical chronology?

Not with real patient records on a consumer plan. ChatGPT's Free and Plus plans include no Business Associate Agreement. Hathr.AI includes a signed BAA on every web app account and runs inside a FedRAMP High boundary, so you can build the chronology on the actual production.

What should a medical chronology template include?

A medical chronology template should include date of service, provider, facility, complaint, findings, assessment, treatment, source citation, source document ID, legibility and confidence, conflict flag and gap to next treatment. Our free 12-field template includes all of them with a worked example.

Last updated October 6, 2026. Informational, not legal advice.

Next: see how Hathr.AI builds and interrogates chronologies on full productions at Hathr.AI for medical record review.