Summary results of 3-stage Delphi consensus exercise addressing minimum standards for longitudinal study design for validation of biomarker reflecting damage endpoints in rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS). Items lacking consensus are indicated in bold type (percentage of respondents voting in support of the item is indicated in parentheses).
| RA | PsA | AS | |
|---|---|---|---|
| Inclusion Criteria | ACR (48%)17, EULAR early referral criteria (26%)18, ANTI-CCP arthritis (25%) | CASPAR19 | Modified New York (67%)20 |
| Pre-radiographic axial (24%)21 | |||
| Treatment strategy | All treatments (68%) | All treatments | All treatments |
| Selection of patient cohort | Consecutive cases | Consecutive cases (67%) | Consecutive cases |
| Inception cohort (33%) | |||
| Study duration | 2 yrs | 4 yrs (69%) | 4 yrs |
| 2 yrs (27%) | |||
| Frequency of assessment | Every 3 mo | Every 6 mo | Every 6 mo |
| Analysis of radiographic endpoint | Blinded to timepoint | Blinded to timepoint | Blinded to timepoint |
| Allow steroid | Yes | Not considered | Not considered |
| Rules for changes in treatment | By predetermined DAS every 3 mo | Not considered | Not considered |
| Frequency of biomarker collection | Q6 mo and prior to new DMARD/anti-TNF | Q6 mo and prior to new DMARD/anti-TNF | Q6 mo and prior to new DMARD/anti-TNF |
| Symptoms | Pain, patient global, fatigue (50%), stiffness (51%) | Pain, skin global, patient global, stiffness (61%), fatigue (40%) | Pain, stiffness, patient global, fatigue (38%) |
| Physical function | Patient self-reported function, objective measures of function (47%) | Patient self-reported function | Patient self-reported function, metrology |
| Psychosocial function | Quality of life | Quality of life | Quality of life |
| Other | Work status, work productivity (53%), participation (42%) | Work status, work productivity (33%), participation (40%) | Work status |
| Disease activity | Joint inflammation, global disease activity (patient/physician), general labs (ESR, CRP), imaging/MRI (62%), imaging/US (31%) | Joint inflammation, global disease activity, (patient/physician), clinical enthesitis, dactylitis, spinal, skin, general labs (ESR, CRP), nail (56%), extraarticular disease (67%) | Joint inflammation, global disease activity (patient/physician), clinical enthesitis, metrology, general labs (ESR, CRP), extraarticular disease, imaging/MRI |
| Radiographic damage endpoint | Modified Sharp | Modified Sharp | mSASSS |
ACR: American College of Rheumatology; EULAR: European League Against Rheumatism; CCP: cyclic citrullinated peptide; CASPAR: CASPAR Study Group Criteria; DAS: Disease Activity Score; DMARD: disease modifying antirheumatic drugs; TNF: tumor necrosis factor; ESR: erythrocyte sedimentation rate; CRP: C-reactive protein; MRI: magnetic resonance imaging; mSASSS: modified Stoke AS Spinal Score; US: ultrasonography.