Marked differences between existing international OAMP models include treatments offered, settings and mode of delivery, intensity, duration and health disciplines involved. There is some evidence of effectiveness from randomised controlled trials (RCTs) and longitudinal cohort studies reporting outcomes from OAMPS in different real-world settings, however, this research is still in its infancy. The effects of different OAMP models have not been compared head-to-head and given the prohibitive costs and logistics associated with comparing OAMP models in RCTs, it is unlikely that these trials will take place. Instead, we will leverage research efforts and costs that have already been spent by combining data from existing cohort studies to compare the outcomes of different OAMP models.
We aim to combine Individual Patient Data (IPD) from the existing international OAMP cohorts and use meta-analytic techniques to address the following objectives: 1) Compare the short-, medium- and long-term changes in pain, physical function, body weight, Quality of Life, fear of movement and goal achievement between different OAMPs. 2) Determine the short-, medium- and long-term overall effects of OAMPs on pain and physical function for people with knee and hip OA. 3) Examine the characteristics of OAMP participants who achieved/ did not achieve the Patient Acceptable Symptom State (PASS), OMERACT-OARSI responder criteria, and completers vs dropouts. 4) Describe the implementation evaluation outcomes of OAMPs
Methods: We will use de-identified IPD from nine existing OAMP clinical cohorts from Australia, Norway, Sweden, Netherlands, UK, New Zealand and USA. Clinical cohorts will be eligible if they are derived from a hip/knee OAMP in a real-world setting with the following components: i) personalised OA care; ii) package of care with reassessment and progression; iii) minimum of two core treatments of education, exercise, and/or weight-loss, and; iv) optional adjunctive treatments. We will include both published and unpublished data.
Based on scoping work on the outcomes measures and time points currently collected by each OAMP, our primary outcomes will be the difference in pain (numerical rating scale 0-10) and function (Western Ontario and McMasters Osteoarthritis Index function score (WOMAC)), at 12-weeks. Secondary outcomes will be changes in pain and function at 26- and 52-weeks. Other secondary outcomes at 12-, 26- and 52- weeks will be changes in: body weight; quality of life (EuroQol, Short Form 12); disease specific measures (Knee Injury and Osteoarthritis Outcome score, Hip Disability and Osteoarthritis Outcome score, WOMAC); functional performance (30-second chair stand test, six-minute walk test); fear of movement; and patient satisfaction. We will report against the PASS, OMERACT-OARSI definition of responders/non-responders and examine implementation outcomes where available including the Osteoarthritis Quality Indicator Questionnaire, uptake, reach and fidelity.
The IPD will be harmonised and aggregated to create one large dataset. We will use descriptive statistics to compare the characteristics of participants across OAMPs. We will take a two-step approach to IPD meta-analytic techniques. First, we will estimate the change in outcomes for each OAMP (pain, function and other outcomes) with multivariable regression modelling. Second, we will weight and pool estimates using random-effects methods to determine the overall effects on pain and function, account for differences in effects across studies and examine prognostic effects and interactions of characteristics (e.g. baseline symptomatic severity, functional performance) of participants who achieved/did not achieve the PASS, OMERACT OARSI responder criteria and those who completed/dropped out of the OAMPs.
Results: This study has received ethical approval from the NSLHD Human Research Ethics Committee (Australia). Ethical approval for use of other cohort data is being sought by researchers in their respective countries. We have performed extensive work with the stakeholders involved to identify appropriate co-collected outcomes and will collaborate with the OA Trial Bank to store and collate the cohort data, the first database of its kind.
Conclusions: This project will be the first to compare patient and implementation outcomes across international OAMPs. It will address a priority of the Initiative and make recommendations on the “optimal” OAMP model/s to use.