The aim of the study is to establish the intrarater-reliability, criterion validity and responsiveness of the ADL-Questionnaire applied on an eHealth platform to be used by patients diagnosed with rheumatoid arthritis.

The study is designed as a repeated test-retest study including 240 patients filling in the ADL-Q, HAQ-DI and PDQ at day 1, 3, 56 and 58. The study provides an eHealth platform (a home-module in the DANBIO database) which makes it possible for the patients to complete their assessments and send information from their own home.

Intrarater reliability will be assessed by calculating the intraclass correlation coefficients (ICCs). Criterion validity will be evaluated based on correlational analysis and responsiveness based on effect sizes, in both cases involving HAQ-DI. PDQ scores will be used to classify participants based on pain phenotype to explore any relationship between pain phenotype and reliability.

Inclusion Criteria:

• Diagnosed with RA ≥ 12 months
• DAS28-CRP < 5,1
• Age between 18 and 85 years
• Computer and Internet connection at home

Exclusion Criteria:

• Blood samples (creatinine, haemoglobin) outside the reference limits +/- 5 % at screening
• Blood samples (thrombocytes and leukocytes) outside the reference limit -/+ 15 % at screening
• Blood samples (ALAT) outside the reference limit -/+ 100 % at screening
• Dementia or other linguistic/cognitive/physical deficiency that prevents participation
• Vision impairment that prevents the use of the devices and computer

All adult patients, diagnosed with RA, referred for regular controls in the rheumatology clinic at Copenhagen University Hospital, Bispebjerg and Frederiksberg, will be screened via the database, DANBIO, for in- and exclusion criteria.