OBJECTIVES: Probabilistic sensitivity analysis (PSA) is a useful tool to assess parameter uncertainty, but being among the more technically advanced methods in cost effectiveness modeling, it is sometimes underutilized.  However, following the incorporation of PSA by NICE, the English HTA agency, into their guidelines in 2005, there was a call for the routine use of PSA in economic modeling. This study investigates whether these two developments have had an effect on cost-effectiveness modelling practice, and also reviews current requirements for PSA in reimbursement guidelines globally. METHODS: The following three journals in which cost effectiveness analyses are most often published were included in the study: Medical Decision Making, Pharmacoeconomics and Value in Health. All papers published in these three journals in 2004 and 2009 respectively were assessed. In addition, pharmacoeconomic guidelines from 31 countries were compared for the requirement of PSA in reimbursement submissions. RESULTS: In the three journals from 2004 to 2009, the overall number of articles presenting cost-effectiveness modelling increased from 41 (2004) to 55 (2009). In 2009, 69% of these articles presented PSA, compared to only 32% in 2004. Of a total of 31 national pharmacoeconomic guidelines, 12 mention PSA. However, only 6 of these require this form of analysis to be included in reimbursement submissions. Many countries with well established requirements for economic analysis in reimbursement submissions, such as Australia, do not require PSA. CONCLUSIONS: The usage of PSA to investigating parameter uncertainty is now common and increasing. The trend is also starting to show in the reimbursement agencies’ guidelines.