Table 1 Eligibility criteria
From: Acute flares of knee osteoarthritis in primary care: a feasibility and pilot case-crossover study
| Inclusion criteria | Mode of ascertainment |
| Male or female aged ≥ 40 years | GPSS |
| Registered as a permanent resident with participating general practices | GPSS |
| Recorded consultation for knee OA or knee OA-related joint symptoms in the last 2 years† | GPSS |
| Access to an email account and to the Internet | PCRF |
| Exclusion criteria | |
| Known diagnosis of inflammatory arthropathy, spondyloarthropathy, or crystal arthropathy (e.g. rheumatoid arthritis, ankylosing spondylitis, reactive arthritis, systemic lupus erythematosus, gout, psoriatic arthritis)† | GPSS |
| Recorded diagnosis of fibromyalgia† | GPSS |
| Red flags: recent significant trauma to knees; acutely hot swollen joint | GPSS, PCRF |
| Previous total knee arthroplasty or on waiting list for total knee arthroplasty | GPSS, PCRF |
| Corticosteroid injection into the knee in the last 3 months | PCRF |
| Surgery to either knee within the past 3 months | GPSS, PCRF |
| Unable to complete questionnaires written in English via the study website | PCRF |
| Vulnerable individuals (e.g. psychiatric illness, learning difficulties, dementia, terminal illness, and severe enduring mental ill health) | GPSS |
