OBJECTIVES: Statins, which vary considerably in their lipid-lowering potencies, are prescribed at non-equivalent doses in Australia. This study sought to estimate the effects of non-equivalent prescribing on low-density lipoprotein cholesterol (LDL-C) levels and cardiovascular risk for the four most commonly prescribed statins. METHODS: The weighted average daily doses (WADDs) of pravastatin, simvastatin, atorvastatin and rosuvastatin prescribed in 2011, in Australia were sourced from Pharmaceutical Benefit Scheme (PBS) data. Dose-specific, LDL-C modifying potencies of these four statins were derived from the meta-analysis by Law et al (BMJ 2003). The relationship between reduction in LDL-C achieved by statin therapy and reduction in cardiovascular risk was derived from the recent meta-regression by the Cholesterol Treatment Trialists’ Collaboration (Lancet 2010). This showed that for every 1mmol/L reduction in LDL-C, the relative risk for a major cardiovascular (coronary and/or stroke) event was 0.78 (95%CI 0.76-0.80).   RESULTS: In 2011 the WADDs for pravastatin, simvastatin, atorvastatin and rosuvastatin were 38.4mg, 36.3mg, 34.2mg and 14.9mg, respectively. The corresponding expected reductions in LDL-C were 29.0%, 37.3%, 48.2% and 44.9%. Assuming a pre-treatment LDL-C of 4.13 mmol/L (the threshold for treatment recommended in international guidelines), these lipid changes translated to expected reductions in the risk of a major cardiovascular event of 26.3%, 33.9%, 43.8% and 40.0% for pravastatin, simvastatin, atorvastatin and rosuvastatin, respectively.  CONCLUSIONS: In Australia, atorvastatin and rosuvastatin are prescribed at higher LDL-C-reducing doses than pravastatin and simvastatin, and hence would be more effective at reducing cardiovascular risk. The advantages of atorvastatin and rosuvastatin will be further enhanced when their acquisition prices fall in 2012.