Remote Monitoring of Axial Spondyloarthritis

The proportion of patients with low disease activity (defined as ASDAS <2.1) at the 6-months follow-up

The proportion of patients with low disease activity (defined as ASDAS <2.1) at the 12- months follow-up

The proportion of patients with low disease activity (defined as ASDAS <2.1) at the 18-months follow-up

Ankylosing Spondylitis Disease Activity Score (ASDAS) is a clinical measure of disease activity calculated from four patient-reported outcomes (PROs) and C-reactive Protein (CRP) (or erythrocyte sedimentation rate (ESR) if CRP is not available). The formula for calculating ASDAS CRP = 0.12 × back pain + 0.06 × duration of morning stiffness + 0.11 × patient global + 0.07 × peripheral pain/swelling + 0.58×Ln(CRP + 1)). Higher values indicate worse outcome.

Monthly for a subgroup among the Remote monitoring group. ASDAS is a clinical measure of disease activity calculated from four PROs and CRP (or ESR if CRP is not available). The formula for calculating ASDAS CRP = 0.12 × back pain + 0.06 × duration of morning stiffness + 0.11 × patient global + 0.07 × peripheral pain/swelling + 0.58×Ln(CRP + 1)). Higher values indicate worse outcome.

Patient-reported disease activity last 7 days on 6 items using a numeric rating scale (NRS) 0-10. The score is the sum (of the first four individual questions and the mean of questions five and six) divided by five. The sum score range 0-10; higher value indicate worse outcome.

Monthly reported by the Remote monitoring group if disease worsening. Patient-reported disease activity last 7 days on 6 items using a NRS 0-10. The score is the sum (of the first four individual questions and the mean of questions five and six) divided by five. The sum score range 0-10; higher value indicate worse outcome.

Reported every third month by the Patient-initiated care group if disease worsening. Patient-reported disease activity last 7 days on 6 items using a NRS 0-10. The score is the sum (of the first four individual questions and the mean of questions five and six) divided by five. The sum score range 0-10; higher value indicate worse outcome.

Reported monthly by the a subgroup among the Remote monitoring group. Patient-reported disease activity last 7 days on 6 items using a NRS 0-10. The score is the sum (of the first four individual questions and the mean of questions five and six) divided by five. The sum score range 0-10; higher value indicate worse outcome.

CRP measured at home in a subgroup among the Remote monitoring group

Patient-reported disease activity last 7 days on a NRS 0-10 ; higher value indicate worse outcome

Monthly reported by the Remote monitoring group. Patient-reported disease activity last 7 days on a NRS 0-10 ; higher value indicate worse outcome

Reported every third month by the Patient-initiated care group: Patient-reported disease activity last 7 days on a NRS 0-10 ; higher value indicate worse outcome

Patient-reported experience of a significant worsening of symptoms (reflecting a flare in disease activity), response options: no, yes, uncertain. If yes or uncertain, they will be asked which date the flare occurred and the number of days it lasted.

Monthly reported by the Remote monitoring group. Patient-reported experience of a significant worsening of symptoms (reflecting a flare in disease activity), response options: no, yes, uncertain. If yes or uncertain, they will be asked which date the flare occurred and the number of days it lasted.

Reported every third month by the Patient-initiated care group. Patient-reported experience of a significant worsening of symptoms (reflecting a flare in disease activity), response options: no, yes, uncertain. If yes or uncertain, they will be asked which date the flare occurred and the number of days it lasted.

10 item questionnaire (NRS 0-10) used to assess disease activity last 7 days. The score is the sum of each individual question divided by 10, higher value indicate worse outcome.

Item no.6 from Work Productivity and Activity Impairment (WPAI): self-reported activity impairment on a NRS 0-10; higher value indicate worse outcome.

Single item with seven-point response scale ranging from "Much worse" to "Much better".

Single item with seven-point response scale ranging from "Much worse" to "Much better".

Self-reported pain level last 7 days hours on a NRS 0-10; higher value indicate worse outcome.

Self-reported joint pain level last 7 days hours on a NRS 0-10; higher value indicate worse outcome.

1 item from Pittsburgh Sleep Quality Index, self-reported sleep impairment in last month due to pain with 4 response categories ranging "Not during the past month" to "Three or more times a week" ; higher value indicate worse outcome.

1 item with five point response options ranging from "Very satisfied" to "Very dissatisfied", higher value indicate better outcome

Remote monitoring and Patient-initiated care groups, number of steps during daytime captured by wearing a smartwatch

Remote monitoring and Patient-initiated care groups, mean pulse level during daytime captured by wearing a smartwatch

6 item utility instrument for measurement of health related quality of life, 5 first items with 5 response categories, item no.6: self-reported health status on a 0-100 mm scale

Self-reported use of NSAIDs and analgesics and national register data from The Norwegian Prescription Register

For the Control group, examiner assessed metacarpophalangeal (MCP) 1-5, proximal interphalangeal (PIP) 1-5, wrists, elbows, shoulders, ankles, forefeet

At extra visits/withdrawals/early discontinuation in the Remote monitoring and Patient-initiated care groups, For the Control group, examiner assessed MCP 1-5, PIP 1-5, wrists, elbows, shoulders, ankles, forefeet

For the Control group, examiner assessed MCP 1-5, PIP 1-5, wrists, elbows, shoulders, ankles, forefeet

At extra visits/withdrawals/early discontinuation in the Remote monitoring and Patient-initiated care groups, For the Control group, examiner assessed MCP1-5, PIP 1-5, wrists, elbows, shoulders, ankles, forefeet

For the Control group, the presence of heel enthesitis is examined clinically by a health professional. Scored as not present/present right heel/present left heel/present both heels.

At extra visits/withdrawals/early discontinuation in the Remote monitoring and Patient-initiated care groups, , the presence of heel enthesitis is examined clinically by a health professional. Scored as not present/present right heel/present left heel/present both heels.

Self-reported way of transport to the hospital; walking or bicycling/private car/public transportation/taxi/airplane/other.

Self-reported travel distance in kilometres to the hospital.

If in paid work, the need to take time off from work is indicated as yes or no.

Self-reported health care use and national register data on consultations and treatment in secondary and primary health care

Number of extra visits to the hospital or video consultations with a health care provider

Number of withdrawals/early discontinuation

Number of adverse events, serious adverse events, and withdrawals because of adverse events.

Self-efficacy/confidence in using smartphone, tablet, computer, app's, secure login and digital health services. 6 items with Likert scale response categories: Never used, Very bad, Bad, Neither good nor bad, Good, Very good. Score range 1-5; higher scores indicate higher self-efficacy.

20 items from 4 domains of the eHealth Literacy Questionnaire (eHLQ). Four point response scale, sum domain score range 1-4. Lower scores indicate lower eHealth literacy.

To what degree do you understand your body's signs and symptoms. Single item, 4-point Likert scale (not at all - to a large degree + do not know-option)

Service User Technology Acceptability Questionnaire (SUTAQ) reported by the Remote monitoring group. 22 items in 5 subscales. Score range 1-6. Higher scores in subscales 1,2 and 5/lower scores in subscales 3 and 4 indicate higher acceptability with telehealth.

Service User Technology Acceptability Questionnaire (SUTAQ) reported by the Patient-initiated care group. 3 of 22 items: #1, #10 and #11. Score range 1-6. Higher scores in indicate higher acceptability with telehealth.

One item on whether the preferred follow-up strategy would be Remote monitoring or Patient-initated care reported by the two intervention groups only.