Few studies address this question. Several show that 70 to 80 percent of CF=
S patients
are women, although some researchers say that these are normal figures for =
any
immune-related illness. Some studies indicate that CFS is less common among=
 lower
income people and minorities, but critics point out that the average CFS pa=
tient sees so
very many doctors before they can get a diagnosis, that only those with gre=
at access to
medical care get counted in such studies, thus giving a bias with regards t=
o income and
race.