1)Inconsistencies in the way sexual orientation is defined make it difficult to compare findings across studies:
Studies have not been consistent in how they define a lesbian sexual orientation, with some focusing on sexual behavior and others focusing on identity or desire.
2) The lack of standard measures, including measures of sexual orientation, makes it difficult to compare findings across studies:
Studies of lesbian health have lacked standard measures of sexual orientation including its three components behavior, identity, and attraction or desire which makes comparisons among studies difficult
3) The use of small, nonprobability samples limits the generalizability of findings:
Most lesbian health studies have relied on nonprobability samples. In particular, many studies have used convenience samples.