Abstract
Objective Psoriatic arthritis (PsA) is a heterogenous condition with musculoskeletal and skin manifestations. The physician visual analogue scale (VAS) is an important component of many composite scores used in clinical trials and observational studies. Currently no training material exists to standardise this assessment.
Methods A novel training infographic was developed with stakeholder involvement, then evaluated in a Latin square design in which 20 patients with PsA were assessed by 10 clinicians. For each group of 10 patients, five assessors conducted 'traditional' assessment (consisting of 66/68 joint count, body surface area, Leeds enthesitis index, dactylitis and nail counts) and five assessors conducted a standardised, thorough general examination informed by the infographic. Assessors switched assessment type between groups. The 3VAS and 4VAS informed by traditional and infographic methods were compared, alongside other composite scores.
Results There was strong agreement between traditional and infographic physician VAS (ICC:0.686, p=0.008). This improved to very strong agreement when incorporated into the 3VAS (ICC:0.989, p<0.001) and 4VAS (ICC:0.994, p<0.001). The duration of assessment was significantly less for the infographic versus traditional groups (6.5 versus 7.8minutes, p<0.001). There was moderately high agreement between the 3VAS and 4VAS categories of disease activity with the same categories defined by PASDAS and DAPSA (x2:17.0, p=0.049).
Conclusion This study has developed and validated a novel training infographic which informs a briefer assessment of the physician global VAS than traditional assessments. This tool has potential applications in training and routine clinical practice.
