Health research examining the disparities faced by gender minorities (transgender, transsexual, and other gender nonconforming individuals) has reached a stage where population based studies are needed in order to expand upon what smaller, community based studies have identified within the population. One of the issues hindering the inclusion of measures needed to identify gender minority populations is the lack of measures that can effectively identify gender minority populations but can be understood by gender majority populations and provide data usable by researchers. This study examined measures that can identify gender identity/gender transition and gender expression by conducting cognitive interviews with 50 people (25 gender minority, 25 gender majority). The interviews asked people to read and answer the questions; afterwards they were interviewed about why they answered the way they did. The gender identity/gender transition question was found to be understood by all participants and only requires small changes to improve its usage. The researchers found gender minority and majority participants to have problems answering the gender expression questions. The results show that the gender expression measures may not be effective when used in a population based study. Researchers conclude that the gender identity/gender transition questions would be effective in quantitative studies and be useful in identifying health disparities among gender minority populations.