Comparison of nail scoring systems used in studies of currently approved treatments for PsO and/or PsA.
| Symptoms | NAPSI,38,39 by Quadrant | Target NAPSI,38,39 per Quadrant | mNAPSI,38,40 Whole Nail | N-NAIL,34 Whole Nail | f-PGA,80 All Nails | |
|---|---|---|---|---|---|---|
| Nail matrix symptoms | Beau lines | – | – | – | Absent = 0; 1 line = 1; | Clear = 0; |
| 2 lines = 2; ≥ 3 lines = 3 | Minimal = 1; | |||||
| Leukonychia | Score 1 for each nail quadrant with nail matrix symptoms (0–4) | Present = 1 | Present = 1 | – | Mild = 2; | |
| Moderate = 3; | ||||||
| Severe = 4 | ||||||
| Nail plate crumbling | Present = 1 | Absent = 0; | Absent = 0; mild = 1; | |||
| 1–25% = 1; 26–50% | moderate = 2; | |||||
| = 2; > 50% = 3 | severe = 3 | |||||
| Pitting | Present = 1 | Absent = 0; 1–10 pits = 1; | Absent = 0; mild = 1; | |||
| 11–49 pits = 2; | moderate = 2; | |||||
| ≥ 50 pits = 3 | severe = 3 | |||||
| Red spots in the lunula | Present = 1 | Present = 1 | – | |||
| Nail bed symptoms | Hyperkeratosis | Score 1 for each nail quadrant with nail bed symptoms (0–4) | Present = 1 | Present = 1 | Absent = 0; 1 mm = 1; | |
| 2 mm = 2; ≥ 3 mm = 3 | ||||||
| Oil drop or salmon patch | Present = 1 | Absent = 0; 1–10% = 1; | Absent = 0; 0–25% = 1; | |||
| 11–30% = 2; > 30% = 3 | 25–50% = 2; > 50% = 3 | |||||
| Onycholysis Splinter hemorrhages | Present = 1 | |||||
| Present = 1 | Present = 1 | – | ||||
| Score range per nail (or “target” nail) | 0–8 | 0–32 | 0–13a | 0–15 | 0–4 | |
| Total for fingernails | 0–80 | – | 0–130a | 0–150 | 0–4 | |
| Total for all nails | 0–160 | – | – | – | 0–4 |
↵a Note that the mNAPSI is sometimes listed as 0–14 per nail, 0–140 total, due to a misprint in the original paper.40
f-PGA: fingernail physician global assessment; mNAPSI: modified NAPSI; NAPSI: Nail Psoriasis Area Severity Index; N-NAIL: Nijmegen-Nail Psoriasis Activity Index Tool; PsA: psoriatic arthritis; PsO: psoriasis.