UAS is calculated based on daily assessments of two key symptoms of urticaria: the number of wheals (hives) and the severity of pruritus (itching), by summing once-daily UAS scores over a 7-day period, with total scores ranging from 0 to 42.
| Score | Wheals | |
| 0 | None | |
| 1 |
|
Mild (<20 wheals/24 hrs) |
| 2 | Moderate (20-50 wheals/24 hrs) | |
| 3 | Intense (>50 wheals/24 hrs or large confluent areas of wheals) | |
| Score | Pruritus | |
| 0 | Intense (severe, interferes with normal daily activity or sleep) | |
| 1 |
|
Mild (present but not annoying or troublesome) |
| 2 | Moderate (troublesome but does not interfere with normal daily activity or sleep) | |
| 3 | Intense (severe, interferes with normal daily activity or sleep) | |