Osteoporosis Bone Density T-Scores: Reading the Numbers on Your Report

Updated 10 October 2026

A bone density report is mostly numbers, and the same score can be described in slightly different words by different organizations. The report in your hands also carries details, such as the site measured and the center, that matter when a later scan is read against it.

This guide sets out what the National Institute of Arthritis and Musculoskeletal and Skin Diseases, MedlinePlus, the Royal Osteoporosis Society and two other sources say about T-scores and Z-scores, followed by a table, a sheet for report numbers, a word list, four steps and a one-page summary.

How NIAMS, MedlinePlus and three other sources word the T-score bands, the Z-score and the survey definition

NIAMS explains the T-score in three lines: "If your T-score is: -1 or higher, your bone is healthy. -1 to -2.5, you have osteopenia, a less severe form of low bone mineral density than osteoporosis. -2.5 or lower, you might have osteoporosis." It adds that "a T-score is the difference between your bone mineral density and 0, which is the bone mineral density of a healthy young adult," and that "the risk of broken bones increases by 1.5 to 2 times with each 1-point drop in the T-score."

MedlinePlus states: "A T-score of -1.0 or higher. This is considered normal bone density. A T-score between -1.0 and -2.4. This means you have low bone density (osteopenia) and may be at risk for developing osteoporosis. A T-score of -2.5 or less. This means you probably have osteoporosis." The Royal Osteoporosis Society draws the same three bands, noting that low bone density "is expected in older adults," and adds that "the scan results are usually put together with other information, including a fracture risk assessment." The Bone Health and Osteoporosis Foundation says "the output of a DXA test is a number called a T-score. Normal is zero (0). The more negative the number, the weaker your bones and the more likely they are to break."

A Z-score is the other number a report may carry. NIAMS says "if your Z-score is -2.0 or less, your bone mineral density is low," and that the Z-score compares you with healthy people of your age, ethnicity and sex. The National Center for Health Statistics defines osteoporosis in survey terms as a bone density value "2.5 SDs or more below the BMD of a young female adult mean value," at the femur neck or lumbar spine or both.

The National Institutes of Health says it briefly: "A T-score of -2.5 or lower means you may have osteoporosis." The wording differs at the edges: -2.4 in one source and -2.5 in another. The sources agree on the shape of the scale, and the category printed on your own report is the one to copy. What the number means for you is a conversation for your clinician, who also weighs other factors.

The score, the site and the scan date from each report can be entered once in My Labs within Osteoporosis Journey (by Health Journey Labs), so they stay together.

A table of the numbers: T-score bands, the Z-score and what each source adds

Setting the sources beside one another shows where they agree and where the wording shifts slightly.

Score bands table, by Osteoporosis Journey

The bands are the same shape in all four. Taking the rows one at a time, the first two differ only in the way the middle band is cut off, the third adds a note about older adults, and the fourth adds the point that a diagnosis is not decided by the score alone. The fracture and FRAX notes show that the T-score is one input among several, so a clinician may reach a conclusion that differs from a simple reading of the number. The guide to what to track with osteoporosis besides a T-score lists the other things worth keeping beside the number.

The band your report prints can be noted beside the score in My Labs of Osteoporosis Journey, in the report's own wording.

A report-reading sheet for each scan: date, site, score, center and what the clinician said

A report is easier to compare with the next one when the same few items are copied from each. The sample rows below are invented and show only the layout.

Scan report table, by Osteoporosis Journey

Give each site its own row, because a report often lists the spine and the hip separately. The Royal Osteoporosis Society says that if you need more scans, "it's best to have them at the same hospital and, if possible, on the same machine," since that makes results easier to compare. (Source: theros.org.uk.) Noting the center and machine on each row lets a clinician see at once whether two scans are directly comparable. If the machine is unknown, write unknown, since an honest blank is more useful than a guess and the clinic can look it up.

Copy the numbers as printed and leave the reading to the clinic. If a report prints several numbers for the same site, such as a total and a regional figure, copy each with the label beside it, and ask the clinic which one it uses when it speaks about your result. The guide to the wait for a bone density follow-up covers the time between scans.

One row per site and scan can be saved as an entry in the Daily Journal of Osteoporosis Journey, with the center added in the same note.

Words for reading a scan report with the clinician: sites, scores, categories and questions

A few plain words for each part of the report make the conversation with the clinician quicker and keep your notes consistent between scans.

Words for scan reports

Osteoporosis Journey copies the site and score words exactly as they appear on the report.

• Site words: lumbar spine, femur neck, hip, forearm, whole body, peripheral scan.
• Score words: T-score, Z-score, as printed, copied, matches the last scan, different center.
• Category words: normal, low bone density, osteopenia, osteoporosis range, as printed.
• Context words: fracture history, FRAX discussed, height measured, results letter.
• Question words: what the number means for me, which scan is the baseline, who explains the change.

Pick the words that match your report and date them. If the report uses a term you do not recognize, write it down as printed and put a question mark beside it, so the clinic can explain it in the room. The Bone Health and Osteoporosis Foundation notes that results from peripheral tests, such as scans of a finger, wrist or heel, are not comparable to central DXA measurements, so write which kind of scan it was. These words describe the report and make no claim about your bones. The clinician interprets the numbers with the rest of your history. Urgent symptoms, such as sudden severe pain after a fall, call for your clinician or local emergency number first.

The category wording from each report can be stored in the Daily Journal of Osteoporosis Journey exactly as printed, with the date.

Four steps for the visit where you go through a bone density report with the clinician

Reports arrive by letter, portal or phone, and the discussion may be days later. A few steps keep the numbers organized until then. They arrange what is already on the page.

Report review steps, by Osteoporosis Journey

1. Copy the date, site, T-score, Z-score and category from the report.
2. Write the center and, if known, the machine beside each row.
3. Add the previous report's numbers on the row above, if you have them.
4. Choose two or three questions, with the clearest first.

From Osteoporosis Journey, we recommend finishing the sheet a day before the appointment (Osteoporosis Journey checklist), so the latest report is on the page.

Questions can be plain, for example which scan the clinic treats as the baseline, how the two centers compare and who will explain a change. The clinic answers them, and a source cannot.

If the clinic offers a follow-up scan, add the request date and the appointment date as two lines, and the guide to tracking osteoporosis labs and DEXA dates shows how to keep those dates in order. A gap between the two is common, and writing it down shows the clinic where time went.

During the visit, write each reply against its question, and note any new date. Ask for a copy of the report if you only have a summary letter, so the printed numbers can go on the sheet.

Questions about a report can wait in My Care Team within Osteoporosis Journey, under the clinician who ordered the scan.

A one-page summary of your scan reports for the clinician: dates, sites, scores and questions

One page lets the clinician see the sequence of your scans before asking anything, and the reports themselves stay in your folder.

Summary of scan reports, by Osteoporosis Journey

• Each scan with its date, center and the site measured.
• The T-score and Z-score as printed on each report.
• The category wording on each report.
• Any fracture or height measure with its date.
• What is pending or unclear.
• Two or three questions for this visit.

Offer the page as the visit opens and suggest going down it row by row. Whatever the clinician adds goes in with its date.

The page copies what the reports print. What the numbers mean, and whether anything should follow, is for your clinician to decide with the full picture, and no page, source or app decides it. Urgent symptoms call for your local emergency number first.

This page leaves Osteoporosis Journey as an export from its Doctor Report, and the dated entries stay behind it.

How Osteoporosis Journey can help

A printout in a folder is a fine start. If you prefer scan numbers, sites and questions in one dated place, the best osteoporosis apps guide compares the options.

Osteoporosis Journey is a personal osteoporosis tracker from Health Journey Labs on the App Store and Google Play. Copied numbers with their site, center and date turn a pile of reports into a sequence a clinician can read. How a score should be read for you is a question for your clinicians, and the sheet hands them the numbers as printed. Below is what you can use and how each part helps.

• My Meds — Logs medicine names, timing, dose; app-specific items: bone medicines, calcium/vitamin D you actually use as directed, pain options your clinician already cleared; read together with movement weeks, sleep, near-falls, the rest of the tracked history.
• Daily check-in — Logs physical symptoms, emotional state, nutrition, sleep, exercise, meds, external factors; app-specific items: pain, movement confidence, near-falls or falls, fear of fracture; read together with the rest of the logged history.
• Daily Journal — Logs free-text notes, voice entry; app-specific items: what movement was limited, footwear or lighting near a stumble, caregiver help, visit debriefs, leftover fear after a fall, a look-fine mismatch line; read together with scores and other logged history (adds context).
• Flare Tracker — Logs flag a day clearly worse than the usual hard week; app-specific items: a real fall, a cluster of near-falls, pain that jumps above baseline; read together with history across weeks (one-off spike vs repeating pattern).
• My Labs — Logs result dates; app-specific items: DEXA, vitamin D, calcium, other bone-related tests; read together with meds, falls, movement, function.
• Learn — Logs short education topics, prompts; app-specific items: meds adherence, falls awareness, cleared movement, visit prep, why fear of falling still belongs in the log; read together with your own logged weeks.
• AI companions — Logs Clara (general chat), specialist companions; app-specific items: knowledge, fitness, nutrition, relationships; read together with your logged history (companions already see it); used for: visit wording; a calm caregiver script; a listening ear after a scary near-fall night.
• Weekly Goals — Logs one small aim, whether it held; read together with real check-ins.
• My Care Team — Logs clinicians, short visit notes; app-specific items: tends to ask mainly about DEXA rather than near-falls; read together with logged history; used for: visit prep (what to ask and bring); notes during the visit; review afterward.
• Doctor Report — Logs one-page summary exported from logged history; app-specific items: dates, meds taken, falls or near-falls, movement, pain, how you functioned; read together with the history already logged; visit type: bone.
• My Assessments — Logs structured check-ins beyond daily scores, onboarding life and social context; read together with ongoing history.
• Food Tracker — Logs meal or drink lines, nutrition; read together with energy, sleep, bone-care.
• Weight Tracker — Logs scale or body notes; read together with the rest of the logged history.
• Period Tracker — Logs start and stop dates, flow, how heavy or light bleeding felt; read together with bone-care or pain, everything else logged.

Everything you log builds one history, and insights get stronger as it grows. Custom symptoms let you add your own labels.

Sources

• National Institute of Arthritis and Musculoskeletal and Skin Diseases: bone mineral density tests, what the numbers mean
• MedlinePlus: bone density scan
• Royal Osteoporosis Society: bone density scan (DXA/DEXA)
• Bone Health and Osteoporosis Foundation: bone density testing
• National Center for Health Statistics: Osteoporosis or Low Bone Mass in Older Adults, United States, 2017-2018
• National Institutes of Health: osteoporosis

FAQ

The answers below draw on the sources cited in this guide, and the app they mention is Osteoporosis Journey (by Health Journey Labs).