Self-reported neck-pain functional disability. Free with attribution.
NDI (Neck Disability Index) is a validated clinical instrument used to assess self-reported neck-pain functional disability. The instrument contains 10 items.
Source / attribution: Vernon H, Mior S. The Neck Disability Index. J Manipulative Physiol Ther. 1991;14(7):409-415.
The instrument's primary construct — self-reported neck-pain functional disability — is operationalized through a fixed set of items, each with a defined response format. This standardisation is what allows NDI scores to be compared meaningfully across clinicians, sites, and studies.
Like all screening or assessment instruments, NDI is a structured aid — not a diagnostic test in isolation. Results should be interpreted alongside history, examination, and clinical context. Where a score crosses an actionable threshold, the next step is typically a more detailed clinical evaluation rather than a definitive diagnosis.
Answer all 10 items below to see your NDI score and interpretation.
Each item is scored on a 6-point scale (0–5). Your score updates live as you answer.
All scoring runs in your browser. No data is sent anywhere — close the tab and the answers are gone.
NDI uses simple summation: each item's selected response is converted to a numeric value, and the values are added to produce a total score. Reverse-scored items are inverted before summation.
Scoring notes: Multiply raw score by 2 to get the conventional NDI percentage.
The cutoffs below are drawn from the published validation literature. Always interpret in clinical context.
| Score range | Band | Interpretation |
|---|---|---|
| 0–4 | No disability (0–8%) | Pain has minimal interference with activities. |
| 5–14 | Mild disability (10–28%) | Pain moderately affects daily activities; consider conservative care. |
| 15–24 | Moderate disability (30–48%) | Pain interferes substantially; structured rehabilitation indicated. |
| 25–34 | Severe disability (50–68%) | Major impairment; multidisciplinary management. |
| 35–50 | Complete disability (70–100%) | Bed-bound or exaggerating; thorough evaluation. |
This is an illustrative walkthrough, not a real patient. Follow the same four steps with your own answers — or use the live calculator at the top of this page.
Read each question and choose the response that best fits. Each response has a number next to it — that number is the item's score. The example below uses illustrative answers.
| # | Item | Example response | Score |
|---|---|---|---|
| 1 | Pain intensity | 1 — Very mild | 1 |
| 2 | Personal care | 1 — Normal but painful | 1 |
| 3 | Lifting | 1 — Heavy with extra pain | 1 |
| 4 | Reading | 1 — Slight pain | 1 |
| 5 | Headaches | 1 — Slight, infrequent | 1 |
| 6 | Concentration | 1 — Slight difficulty | 1 |
| 7 | Work | 1 — Usual work only | 1 |
| 8 | Driving (omit if N/A) | 1 — Slight pain | 1 |
| 9 | Sleeping | 1 — Slightly disturbed (< 1 h) | 1 |
| 10 | Recreation | 1 — All but with some pain | 1 |
Add up all the item scores you noted in Step 1.
1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 = 10
Find the row in the interpretation table whose range contains your total:
Total = 10 falls between 5 and 14 → Mild disability (10–28%)
Mild disability (10–28%). Pain moderately affects daily activities; consider conservative care.
A score is one input alongside history and examination. NDI supports clinical judgment — it does not replace it.
If NDI doesn't fit your context, related instruments in orthopaedics include:
| Scale | Measures | Items | Time |
|---|---|---|---|
| ODI | Self-reported low-back-pain functional disability | 10 | — |
| Oxford Knee Score | Pain and function after total knee replacement | 12 | — |
| Oxford Hip Score | Pain and function after total hip replacement | 12 | — |
| LEFS | Function with lower-extremity musculoskeletal disorders | 20 | — |
| BASFI | Functional limitation in ankylosing spondylitis | 10 | — |
| IPSS | Lower-urinary-tract symptoms in men | 7 | — |
| IIEF-5 / SHIM | Erectile dysfunction screen | 5 | — |
| DLQI | Skin-disease impact on health-related quality of life | 10 | ≈ 2 minutes |
NDI (Neck Disability Index) is a validated instrument that assesses self-reported neck-pain functional disability. It is designed for clinicians, medical students, evidence-synthesis researchers. The 10 items are summed to produce a total score.
NDI contains 10 items. Item scores are summed to produce the total. Scores run from 0 to 50, grouped into 5 interpretation bands from ‘No disability (0–8%)’ up to ‘Complete disability (70–100%)’.
On the NDI (total score 0–50), scores of 35–50 fall in the ‘Complete disability (70–100%)’ band — interpreted as: Bed-bound or exaggerating; thorough evaluation. The full ladder is: 0–4 — No disability (0–8%): Pain has minimal interference with activities.; 5–14 — Mild disability (10–28%): Pain moderately affects daily activities; consider conservative care.; 15–24 — Moderate disability (30–48%): Pain interferes substantially; structured rehabilitation indicated.; 25–34 — Severe disability (50–68%): Major impairment; multidisciplinary management.; 35–50 — Complete disability (70–100%): Bed-bound or exaggerating; thorough evaluation. A higher score reflects a more severe presentation, and crossing a cutoff is a prompt to step up assessment or care — but these bands are screening thresholds, not diagnoses.
Scores of 0–4 fall in the ‘No disability (0–8%)’ band: Pain has minimal interference with activities. A low score is reassuring but does not by itself rule out the underlying condition — if symptoms or clinical suspicion persist, reassess over time or use a complementary evaluation rather than relying on the number alone.
NDI is free to use with attribution — clinical, educational, and research use is permitted provided the original source is credited. If you publish results or reproduce the scale, include the citation to the source paper.
Vernon H, Mior S. The Neck Disability Index. J Manipulative Physiol Ther. 1991;14(7):409-415. This is the original publication for the NDI — the reference to cite when reporting results.
No. NDI is a structured assessment aid, not a diagnostic test. Its proper role is clinical assessment of self-reported neck-pain functional disability — it standardizes assessment and flags who needs closer evaluation, but the result must be weighed alongside history, examination, and clinical context. When a score conflicts with your clinical impression, clinical judgment takes precedence; treatment decisions should never rest on a screening score alone.
NDI is supported by the following peer-reviewed sources: