1. Radiological scoring in Psoriatic Arthritis
Application of the OMERACT filter to four scoring methods

2. Radiological scoring methods for PsA
Four methods described
Modified Steinbrocker
Ratingen method for PsA
Sharp method for PsA
Sharp/van der Heijde method for PsA
All originally developed and tested for RA
Addition of DIPs of the hands as a scoring site

3. Specific features in radiographs of PsA
Joint pattern
DIPs and PIPs, asymmetric and frequently in a ray-pattern
Wrist and isolated ray
Symmetrical as in RA
Features
Destruction (widening, osteolysis, pencil-in-cup)
Proliferation (shaft metacarpal/tarsal, adjacent to joints, ankylosis)

4. Comparison of sites/features included in scoring
modified Steinbrocker
Ratingen
Sharp
Sharp/van der Heijde
Films
hands/feet
Erosions
JSN
Malalignment
Proliferation
Global - X
Range
0-160
0-360
0-470
0-528

5. Methods: OMERACT filter
Truth : does the method measure what it should measure?
Discrimination: Reliability, discrimination between patients, and sensitivity to change over time
Feasibility
Boers J Rheumatol 1998;25:198-9

6. Application in clinical trials
Sharp and Sharp/van der Heijde method
Proven sensitivity to change over short periods of time (24 – 52 weeks)
Addition of DIPs of little extra value
Trial duration too short to pick up change in pencil in cup, tuft resorption, periostitis, osteolysis

7. Plan for OMERACT 8
Scoring of the radiographs of IMPACT 1 by four different methods
Involvement of developers of all methods
Information on discrimintation
Test-retest reliability
Sensitivity to change
Information on feasibility