GUIDES
Read your health paperwork with confidence
Walkthroughs of whole documents, and answers to the questions people ask with one in their hand.
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Document walkthroughs
Each one explains a kind of document line by line, with an invented example and the questions worth asking.
- INSURANCE EOBHow to read an explanation of benefits (EOB)What each line on an insurance EOB means — billed, allowed, plan paid, what you may owe — with a worked example and what to check before you pay the bill.
- MEDICAL BILLHow to understand a medical bill (and spot errors)What the charges, codes and adjustments on a medical bill mean, a worked example, and a checklist of errors to look for before you pay.
- LAB RESULTSHow to read your lab resultsWhat the columns on a blood test report mean — result, units, reference range, flags — with a worked example and questions to ask your doctor.
- DISCHARGE SUMMARYHow to understand your hospital discharge summaryWhat each section of a hospital discharge summary means — diagnosis, procedures, medication changes, follow-up — with a worked example and questions to ask.
Insurance EOBs and claims
The words on an explanation of benefits, and what to do when a claim is denied.
- EOB VS BILLEOB vs medical bill: what’s the difference?An EOB comes from your insurer and is not a request for payment; the bill comes from the provider. How to tell them apart and match one to the other.
- PATIENT RESPONSIBILITYWhat does “patient responsibility” mean on an EOB?Patient responsibility is the part of a claim your plan did not pay — deductible, copay, coinsurance or non-covered amounts. How it is worked out.
- ALLOWED AMOUNTWhat is the “allowed amount” on an EOB?The allowed amount is the most your plan will pay for a covered service, also called the negotiated rate. Why it is lower than the billed amount.
- DEDUCTIBLE, COPAY, COINSURANCEDeductible vs copay vs coinsurance on your EOBHow a deductible, a copay and coinsurance differ, how each shows up on an EOB, and how they add up to what you may owe the provider.
- OUT-OF-POCKET MAXIMUMOut-of-pocket maximum explained, using your EOBThe out-of-pocket maximum is the most you pay for covered in-network care in a plan year. What counts towards it and how to track it.
- DENIED CLAIMClaim denied on your EOB? What it means and how to appealWhat a denied claim on an EOB means, how to find the reason, and the internal appeal and external review steps HealthCare.gov describes.
- REMARK CODESWhat do the remark codes on an EOB mean?Remark and reason codes explain why an insurer adjusted or denied part of a claim. Where to find the key on your EOB and what to ask.
- OUT OF NETWORKOut of network on your EOB? Balance billing explainedWhat “out of network” means on an EOB, what balance billing is, and when the No Surprises Act protects you from surprise medical bills.
Medical bills and codes
Billing codes, surprise bills, estimates and how to check a bill before you pay.
- CPT CODESWhat is a CPT code on my medical bill?CPT codes are five-character codes for what a provider did — a visit, test or procedure. How to read them on a bill and why they matter.
- ICD-10 CODESWhat is an ICD-10 code on a medical bill or EOB?ICD-10 codes describe the diagnosis or reason for care on a claim. How to read them, how they differ from CPT codes, and why they affect coverage.
- CHECK A BILLHow to check a hospital bill for errors, step by stepA step-by-step way to check a hospital bill: get the itemized bill, match it to your EOB, look for duplicates, and what to ask before you pay.
- TWO BILLSWhy did I get two bills for one hospital visit?Hospitals and the clinicians who treat you often bill separately. How facility and professional bills differ and how to match each to an EOB.
- ER VISIT LEVELSER visit levels 99281–99285 on a bill, explainedEmergency department visits are billed at five levels, CPT 99281 to 99285. What the level means, what it doesn’t, and what to ask.
- GOOD FAITH ESTIMATEGood faith estimate: what it is and the $400 ruleIf you’re uninsured or self-paying, providers usually must give a good faith estimate. What it covers and when you can dispute a bill.
Lab and blood test results
What common blood tests measure and how the numbers on the report are laid out.
- REFERENCE RANGEWhat does “reference range” mean on lab results?A reference range is the span of results seen in most healthy people, for that lab and method. Why results outside it aren’t always a problem.
- CBC / FULL BLOOD COUNTCBC blood test results explained (full blood count)What each line on a complete blood count (CBC, or full blood count) measures — red cells, hemoglobin, MCV, white cells, platelets.
- MCVWhat does high or low MCV mean on a blood test?MCV is the average size of your red blood cells. What a high or low MCV is generally linked with, and why it is read with your other results.
- LIPID PANELLipid panel (cholesterol test) results explainedWhat total cholesterol, LDL, HDL, non-HDL and triglycerides mean on a lipid panel, and why US and UK reports use different units.
- HBA1CHbA1c result explained: % and mmol/molHbA1c shows your average blood sugar over 2–3 months. How it is reported in % and mmol/mol, the ranges used, and what can affect it.
- EGFReGFR result explained: what the number meanseGFR estimates how well your kidneys filter blood, calculated from creatinine. How it is reported, the stages used, and what can affect it.
- CMP / METABOLIC PANELComprehensive metabolic panel (CMP) results explainedWhat the 14 tests in a CMP measure — glucose, electrolytes, kidney and liver tests, proteins — and how a BMP differs.
- TSH / THYROIDTSH and thyroid test results explainedTSH is the hormone that tells your thyroid how hard to work. Why high TSH and low TSH point in opposite directions, and how T4 fits in.
Hospital paperwork
The shorthand on discharge summaries and medicines lists.
Looking for the wording on an X-ray, CT, MRI or ultrasound report? Radily’s radiology report phrase guides cover it. Everything here is general information, not medical or financial advice.