One of the reasons given for following family history is its use in family medicine. General practitioners frequently question their patients about family history of disease.
Now a Canadian-British systematic literature review casts doubt on the utility of such questioning. The study is Systematic Review: Family History in Risk Assessment for Common Diseases, published in Annals of Internal Medicine, 2009 151;12:878-885. www.acponline.org/annalspdaservices/current/200912150-00177-abstract.shtml
Some of the reported findings are:
Two uncontrolled studies provided insufficient evidence to assess whether querying about family history improves any outcomes.
One randomized, controlled trial and 2 uncontrolled studies provided weak evidence that some patients experienced a reversible, short-term increase in anxiety associated with family history taking.
Twenty-three studies suggested that absence of disease in relatives was more accurately reported than presence of disease and that reporting accuracy was higher for information related to first-degree relatives than more distant relatives.
The study concludes that insufficient evidence exists to evaluate how to collect family history information accurately in the primary care setting and the effects of taking family history on patient outcomes. Patients seem to correctly report the absence of disease in relatives more often than the presence of disease.
It should hardly be surprising that questions on ancestor's health, further back than the present and the immediately previous generation, yield anything of clear value for medicine. Most people know little of their family history, let alone details of previous generation's health.
If this evidence is so valuable why wouldn't the medical profession ask clients to supply documentary evidence showing ancestors' medical history?