Feasibility of a Web-based, Peer-supported Exercise Program for Patients With Hip and/or Knee Osteoarthritis

Time (hours/minutes) per participant-peer-support contact (frequency of contacts divided by total time used by peer-supporters).

Time (hours/minutes) per week per participant used on web-based exercise program delivery.

Time (hours/minutes) per week per participant used on motivational message delivery.

Proportion of received exercise diaries (0-12 per participant).

Proportion of participants providing activity monitor data (at least 4 days, including one weekend day, with minimum 10 hours recording per day) at baseline.

Proportion of participants completing the indirect maximal cardiorespiratory exercise test according to test-protocol at baseline.

Proportion of potentially eligible participants approached that are invited.

Proportion of eligible patients enrolled.

Proportion of enrolled participants providing data at 12 week post-test.

Total number of adverse events (by cause if possible) evaluated by answers at post-test: The four questions addressing possible adverse events: 1) Have you carried out any type of treatment during the last 3 months? (With treatment we mean medication, physical exercise, self-management course or any alternative treatments) (yes/no), 2) If yes, have you experienced any adverse event as a result of the treatment? (yes/no). 3) If yes, which adverse events as a result of treatment? 4) In your opinion, which treatment(s) do you think the adverse event was/were caused by? (medication, physical exercise, self-management course, alternative treatments, other) (Elaborate).

Assessed by accelerometer (ActiGraph GT3X+): Change in physical activity level measured as counts per minute (CPM), which is the total number of registered counts for all valid days divided by wear time. Thresholds for CPM will be used in calculation of time (minutes per week/day) spent on sitting (<100 CPM), and on light (100-2019 CPM), moderate-(>2019-5998 CPM) and vigorous (>5998) intensity physical activity.

Change in VO2 peak measured by indirect maximal cardiorespiratory exercise test (modified Balke-protocol). The indirect estimation of VO2 peak by prediction equations is based on incline, grade and speed at end stage, weight and age.

Change in the last week disability on five subscales; pain (10 items, scale 0-40), symptoms (5 items, scale 0-20), function in daily living (17 items, scale 0-68), function in sport and recreation (4 items, scale 0-16) and quality of life (4 items, scale 0-16). Items are scored by a five-point Likert scale ranging from 0 (least severe) to 4 (most severe). Total sum-score and subscale sum-scores will be converted to normalized scores ranging from 0 (extreme disability) to 100 (no disability).

Change in the last week disability on five subscales; pain (9 items, scale 0-36), symptoms (7 items, scale 0-28), function in daily living (17 items, scale 0-68), function in sport and recreation (5 items, scale 0-20) and quality of life (4 items, scale 0-16). Items are scored by a five-point Likert scale ranging from 0 (least severe) to 4 (most severe). Total sum-score and subscale sum-scores will be converted to normalized scores ranging from 0 (extreme disability) to 100 (no disability).

Patients will address one to three activities they have problems performing due to osteoarthritis. The degree of difficulty with performing these activities is rated from 0 (cannot perform the activity) to 10 (no problems).

Measured by The International Physical Activity Questionnaire-Short Form: Change in time (minutes per week/day) and Metabolic Equivalent of Task (MET-minutes per week/day) spent on sitting, walking, and moderate- and vigorous intensity physical activity the last week (0-7 days). METs are calculated by using the corresponding MET-values for walking (3.3 MET), and moderate-(4.0 MET) and vigorous (8.0 MET) intensity physical activity.

Measured by the three questions from the Nord-Trøndelag Health study (HUNT): change in average frequency (never/<1 per week/1 per week/2-3 per week/almost every day), intensity (easy without losing my breath or breaking into a sweat/so hard that I lose my breath and break into a sweat/I push myself to near-exhaustion) and duration (less than 15 minutes/15-29 minutes/30 minutes to 1 hour/more than 1 hour) of physical activity.

Measured by numeric rating scale ranging from 0 (no pain) to 10 (worst pain).

Measured by numeric rating scale ranging from 0 (no fatigue) to 10 (worst fatigue).

Measured by numeric rating scale ranging from 0 (good, no symptoms) to 10 (very bad, much symptoms).

EQ-5D-5L will be used for measuring health-related quality of life (www.euroqol.org): comprises five dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension has five levels of answers (no problems, slight problems, moderate problems, severe problems, and extreme problems). The average score on each dimension will be reported, and the total score can be calculated into an index value ranging from -0.59 to 1, where -0.59 represents worst possible state and 1 represents perfect health.

Measured by Arthritis Self-Efficacy Scale (ASES): comprises 11 items addressing pain and symptoms (scored on a 5-point scale ranging from not confident at all to very confident). The scores are summed up to a 0-100 score where higher score indicate better self-efficacy.

Measured by Exercise Beliefs and Exercise Habits questionnaire: comprises 20 items addressing exercise self-efficacy (4 items), barriers to exercise (3 items), benefits of exercise (5 items), and impact of exercise on arthritis (8 items), scored on a 5-point Likert scale ranging from strongly disagree to strongly agree. The scores on each subscale is summed up where higher scores indicate better self-efficacy.

Proportion of enrolled participants attending a 5-hour osteoarthritis learning and mastery-course (attendance registered by yes/no).

Total number of exercise sessions.

Average number of exercise sessions per week.

Total number of weeks with minimum one exercise session.

Total number of exercise sessions completed according to prescribed duration. Measured by a question about completion of the prescribed exercise-session (yes/no).

Total number of exercise sessions completed according to prescribed intensity. Measured by self-reported Rating of Perceived Exertion Scale (Borg RPE) ranging from 6 (resting) to 20 (maximal intensity).

Registered by self-report: 1) frequency (number of consultations the last 6 months) with a general practitioner and specialist health care (rheumatologist, orthopedist, neurologist, other), 2) referred (yes/no, the last 6 months) to x-ray, magnetic resonance imaging, physiotherapist, healthy life center, occupational therapist, 3) frequency (number of consultations during the last 6 months) with a physiotherapist, manual therapist, chiropractor, alternative treatment, other due, 4) had a stay at a rehabilitation institution during the last 6 months (yes/no and number of days). Descriptive data will be reported.

Registered by self-report: Frequency (never/<1 per month/monthly/weekly/daily/several times per day) of medication use (addressing pain, sleeping, depression, anxiety) the last 3 months will be self-reported through type, name and dosage (mg) of medication, in addition to use of other medication (yes/no) and type. Descriptive data will be reported.

Change in osteoarthritis pain (from baseline to post-test) measured by a 7-point Global Rating of Change scale ranging from -3 (much worse) to +3 (much better).