S: TRENDS & QUALITY INDICATORS Smith MD, McGhan WF ISPOR, Lawrenceville, NJ, USA; University of the Sciences, Philadelphia, PA, USA OBJECTIVES: The purpose of this study was to perform a longitudinal content analysis to assess trends in pharmacoeconomic and outcomes research abstracts presented at ISPOR Annual Meetings and European Congresses as given in The ISPOR Research Digest at www.ispor.org, as well as to assess abstract quality indicators. METHODS: A database of 4605 abstracts accepted for presentation at ISPOR meetings from 1998 through 2004 were analyzed for trends and quality indicators. Trends were determined for topics and diseases. Quality indicators were defined as abstracts including “study perspective,” statistical considerations (“confidence interval”, “standard deviation”, “±”, “mean/median”, “sensitivity analysis”), or “discounting”. RESULTS: ISPOR had 14 Annual Meetings/Congresses during 1998–2004. The annual number of abstracts increased from 270 to 1013 with a seven-year total of 4605 with all topics and disease categories increasing over time. The major topic areas covered were cost evaluations (42%), clinical outcomes (7%), quality-of-life/patient preferences (12%), methods and concepts (17%) [43 % of which were on quality-of-life and 28% on cost methods], and health policy (22%). The top four diseases (3959 disease-specified abstracts) were cardiovascular (17%), cancer (9%), neurological/mental health (19%), and infectious diseases (8%). With respect to quality indicators, a study perspective was mentioned in 19% and discounting in 7% of the abstracts. For statistical considerations, the percent of abstracts mentioning mean/median (34%), sensitivity analysis (17%), standard deviation (12%), and confidence intervals (4%). The number of abstracts with each of these quality indicators increased over the study period. CONCLUSION: The number of abstracts has increased over the study period for all topics and diseases. Although the general abstract quality, as measured in this analysis, was increasing, the percent of abstracts that include these quality indicators needs improvement. Standards should be adopted for the content of pharmacoeconomics and outcomes research abstracts to provide more useful and meaningful information.