The Leeds Dactylitis Index (LDI) is an instrument to measure the activity of dactylitis in psoriatic arthritis. Dactylitis is a key feature of this disease, a poor prognostic marker and a target for treatment. Almost all new drugs tested in psoriatic arthritis are tested using this metric
The Leeds Dactylitis Index measures the severity and activity of dactylitis. It includes a measuring instrument (dactylometer) and uses an algorithm to calculate the index.