Patient-reported outcomes (PRO) are key endpoint measures to examine and assess preferences for health improvements. Conjoint analysis (CA), traditionally used in marketing studies to examine tradeoffs among attributes, has gained popularity in health care and PRO studies. However, the use of CA and the type of CA studies performed in health care has not been fully characterized. In this study, we characterized the current trends for CA, classified CA studies by area of focus, examined study complexity, and provided recommendations for future research. Literature reviews were conducted using a multi-database search from 2000 to 2008. Review articles, methodological, and non-health related CA studies were excluded. Preference studies were coupled with key words such as: conjoint, health, disease, evaluation, discrete choice and outcome(s). Five years were selected for detailed content analysis and re-checked for accuracy. For the five years examined, there was an upward trend for the number of health-related CA studies (2000=22; 2002=39; 2004=38; 2006=56; 2008=70). However, results from Chi-square analysis revealed no significant differences among years for the general area of focus for CA studies performed. The largest proportion of CA studies consisted of attribute importance, risk, and pharmacoeconomics studies where utility estimates were used to assess willingness-to-pay, quality of life, or quality-adjusted life years. Other applications included disease screening, value of services, satisfaction, treatment evaluation and service delivery. The use of CA to assess PROs in health research has expanded. Recent and more innovative applications have extended to adherence, disease screening, technology, and value. More research is needed to evaluate the usefulness of CA for large database studies and for economic analyses in health technology assessment.