Reliability of Self-Reported Cancer History Varies
Differences between cancer patients and controls could skew study results
WEDNESDAY, Jan. 4 (HealthDay News) -- The reliability of self-reported cancer data varies widely between cancer patients and controls, potentially skewing study results, according to a study in the Jan. 4 issue of the Journal of the National Cancer Institute.
Ellen T. Chang, Sc.D., of the Karolinska Institute in Stockholm, Sweden, and colleagues calculated the sensitivity and specificity of self-reported familial cancer data from 1,508 malignant lymphoma patients and 1,229 controls who completed a telephone interview about cancer in family members.
The researchers found that the lymphoma patients reported family history of any cancer with significantly higher sensitivity than controls, but with marginally lower specificity. The cancer patients also reported false-positive cases of cancer in the family more often than controls, the report indicates.
Self-reported cancer data are "far from perfectly reliable," the authors conclude. "Reliability of self-reported family history of cancer varies between case patients and control subjects," they write. "Recall bias may thus produce biased results in case-control studies of familial cancer risk."