In reply
The reliance on informants for information on the relatives of an index subject is an inherent limitation of the family history method. However, in contrast to the weak sensitivity observed by Huen and Maier, a recent study of the validity of this method suggests that, despite this limitation, highly accurate information can be obtained.1 Although the Dementia Questionnaire2 was used to finally diagnose PPD in relatives, Huen and Maier's use of the Family History Questionnaire3 as a screening tool may have contributed to the poor sensitivity observed because that instrument was not primarily designed to screen for dementia. Our approach has been to apply the Dementia Questionnaire when there was even a slight indication of memory or other cognitive problems as elicited by the Alzheimer's Disease Risk Questionnaire.4 Furthermore, as noted in our article,5 for investigations of late-onset diseases such as Alzheimer's disease (AD), there is