The family history method: whose psychiatric history is measured?
OBJECTIVE
The family history method, in which an informant is asked about the history of psychiatric illness in relatives, is widely used in psychiatric research. Previous research has examined the influence on family history information of characteristics of the relative. In this report, the authors seek to clarify the impact on family history reporting of the psychiatric history of the informant.


METHODS
Both members of female twin pairs from a population-based twin registry were asked about the history of major depression, generalized anxiety disorder, and alcoholism in their mother and father. The authors examined twin pairs discordant for each of the three diagnoses and predicted that the affected twin would report higher rates of the same disorder in her parent than would the unaffected twin.


RESULTS
Twins with a history of major depression or generalized anxiety disorder but not twins with alcoholism were significantly more likely to report the same disorder in their parents than were their unaffected co-twins.


CONCLUSIONS
For major depression and generalized anxiety disorder, a family history diagnosis appears to reflect the psychiatric history of both the relative and the informant. Caution may be needed in the interpretation of results based on the family history method, although the magnitude of this problem may be attenuated by the use of multiple informants.
Kendler
K S
KS
Department of Psychiatry, Medical College of Virginia/Virginia Commonwealth University, Richmond 23298-0710.
Silberg
J L
JL
Neale
M C
MC
Kessler
R C
RC
Heath
A C
AC
Eaves
L J
LJ
D000437:Alcoholism / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D001008:Anxiety Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D003866:Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D004200:Diseases in Twins; D005190:Family; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D008487:Medical History Taking; D001523:Mental Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics; D012042:Registries; D012107:Research Design; D014768:Virginia / Q000453:epidemiology