The aim of this observational study is to compare the use of an extended release paracetamol formulation with standard paracetamol in a cohort of Australian concessional patients with osteoarthritis (OA), to assess differences in prescribing patterns and patient compliance.

This retrospective analysis of physician prescribing data (long-term concessional cohort from the Medicare Australia PBS claims dataset for the time period 2008-2011 (4 years) will compare the use of extended release paracetamol (Panadol Osteo) with standard paracetamol 500mg in a cohort of Australian concessional patients with OA, to assess differences in prescribing patterns and patient compliance.

Inclusion Criteria:

• Participants prescribed with a paracetamol product and categorized as a concessional patient
• Participants with new episodes of OA (no history of OA paracetamol in previous 12 months) or suffering from chronic OA (history of OA paracetamol in the previous 12 months)

Exclusion Criteria:

• Participants with Rheumatoid arthritis or other auto-immune inflammatory conditions
• Participants receiving the following anti-rheumatoid therapies:Immunimodulators such as methotrexate, leflunamide and TNF blockers
• Participants receiving treatment for cancer pain

Cohort of Australian concessional patients with osteoarthritis