CONCLUSIONS At least one PROM with some evidence for aspects of validity and reliability was available for six of the eight m and atory domains of the PsA COS
BACKGROUND An up date d psoriatic arthritis ( PsA ) core outcome set ( COS ) for r and omized controlled trials ( RCTs ) was endorsed at the Outcome Measures in Rheumatology ( OMERACT ) meeting in 2016 .
OBJECTIVES To synthesize the evidence on measurement properties of patient reported outcome measures ( PROMs ) for PsA and thereby contribute to development of a PsA core outcome measurement set ( COMS ) as described by the OMERACT Filter 2.0 .
The Worst Itch Numeric Rating Scale for patients with moderate to severe plaque psoriasis or psoriatic arthritis.
Plaque psoriasis ( PP ) and psoriatic arthritis ( PsA ) are autoinflammatory chronic conditions associated with skin involvement . Pruritus , or itching , is a prevalent and bothersome symptom in patients with PP and is associated with reduced health-related quality of life . The Worst Itch Numeric Rating Scale ( WI-NRS ) has been developed as a simple , single item with which to assess the patient-reported severity of this symptom at its most intense during the previous 24-hour period . Qualitative research was undertaken to assess the content validity of the WI-NRS . Patients with moderate to severe PP and patients with PsA were recruited from clinical sites in the USA . The qualitative research entailed two-part interviews , which began with concept elicitation to gain underst and ing of patients ' experiences of itching , followed by cognitive debriefing of the WI-NRS to assess the instrument 's underst and ability , clarity , and degree of appropriateness from the patient 's perspective . Twelve patients with PP and 22 with PsA participated in the study . Patients reported that itching was an important and relevant symptom of their psoriatic disease . The WI-NRS was reported to be complete and easy to underst and ; the recall period was considered appropriate , the response scale was familiar , and , overall , the instrument was found to be appropriate for assessing itching severity . Patient responses support the content validity of the WI-NRS . The psychometric properties of the tool will be evaluated in future studies
CONCLUSIONS At least one PROM with some evidence for aspects of validity and reliability was available for six of the eight m and atory domains of the PsA COS
BACKGROUND An up date d psoriatic arthritis ( PsA ) core outcome set ( COS ) for r and omized controlled trials ( RCTs ) was endorsed at the Outcome Measures in Rheumatology ( OMERACT ) meeting in 2016 .
OBJECTIVES To synthesize the evidence on measurement properties of patient reported outcome measures ( PROMs ) for PsA and thereby contribute to development of a PsA core outcome measurement set ( COMS ) as described by the OMERACT Filter 2.0 .