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A nonparametric method for automatic correction of intensity nonuniformity in MRI data
John G. Sled, Alex P. Zijdenbos, Alan Charles Evans. IEEE Transactions on Medical Imaging, 1998
Topic: Risk, prevention and care in population studies
A novel approach to correcting for intensity nonuniformity in magnetic resonance (MR) data is described that achieves high performance without requiring a model of the tissue classes present. The method has the advantage that it can be applied at an early stage in an automated data analysis, before a tissue model is available. Described as nonparametric nonuniform intensity normalization (N3), the method is independent of pulse sequence and insensitive to pathological data that might otherwise violate model assumptions. To eliminate the dependence of the field estimate on anatomy, an iterative approach is employed to estimate both the multiplicative bias field and the distribution of the true tissue intensities. The performance of this method is evaluated using both real and simulated MR data.
Why it matters
Describes N3, a method for automatically correcting uneven brightness (intensity nonuniformity) in MRI data without needing a model of the tissue types present. It is a technical imaging method, not a study of dementia.
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How this study scored 55/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on strength of evidence, so that was left out: it earned 52 of the 95 points we could judge it on, which is 55 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (IEEE Transactions on Medical Imaging) |
| Journal's citation record | 3 / 4 | IEEE Transactions on Medical Imaging: journal h-index 329 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | — / 5 | No evidence rating recorded — left out of this score |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 1998 — older than 20 years, still counted |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 7 / 7 | Cited 4,762 times (OpenAlex, 2026-10-10) |
| Citations per year | 5 / 5 | 158.7 citations a year over 30 year(s) since 1998 |
| Impact for its field and year | 5 / 6 | Cited 39.7× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 4 / 4 | Cited 402 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Alan Charles Evans: h-index 190 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | McGill University: institution h-index 1,373 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 2 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 9617910) |
| Free to read | 2 / 2 | Free to read |
| Points | 52 / 95 | Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 52 of the 95 points we could judge it on is 55 out of 100. |
| Total | 55 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
- DOI: 10.1109/42.668698
- PubMed: 9617910
- Original source →
- Free full text: eScholarship@McGill (McGill) →
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Sled, J. G., Zijdenbos, A. P., & Evans, A. C. (1998). A nonparametric method for automatic correction of intensity nonuniformity in MRI data. IEEE Transactions on Medical Imaging. https://doi.org/10.1109/42.668698
Vancouver
Sled JG, Zijdenbos AP, Evans AC. A nonparametric method for automatic correction of intensity nonuniformity in MRI data. IEEE Transactions on Medical Imaging. 1998. doi:10.1109/42.668698. PMID: 9617910.
BibTeX
@article{sled1998-9617910,
author = {Sled, John G. and Zijdenbos, Alex P. and Evans, Alan Charles},
title = {{A nonparametric method for automatic correction of intensity nonuniformity in MRI data}},
journal = {IEEE Transactions on Medical Imaging},
year = {1998},
doi = {10.1109/42.668698},
pmid = {9617910},
url = {https://doi.org/10.1109/42.668698}
}