This study will find out how people who received physiotherapy for their osteoarthritis of the hip/knee or chronic low back pain felt about the treatment they received in a research trial that is being run in primary care physiotherapy clinics in Dublin and Kildare. Patients in the study were treated in either a group class called SOLAS [i.e. Self-Management of Osteoarthritis and Low back pain through Activity and Skills] or usual individual physiotherapy care. The SOLAS class aimed to help people to learn how to manage their pain themselves, called self-management. Physiotherapists helped patients to manage their pain by supporting them to be physically active [eg walking], to do exercises for their joints and muscles, to understand more about how to manage pain using medication, heat and ice, how to cope with pain using relaxation skills, and how to manage their body weight if that was increasing their pain. Certain factors may influence how well people can self-manage their pain and this study will help us to find out if these factors influenced the patients in the study. These factors are how well people understand and know how to self-manage, how confident, positive and motivated people feel about self-managing and how well they can monitor their own behaviour for example by using an activity diary or a pedometer. We interviewed some patients who took part in the research trial about these factors and we will be able to see what effect the treatment had on them by analysing these interviews.