REPORTING BILATERALITY STATUS IN 1ST-DEGREE RELATIVES WITH BREAST-CANCER - A VALIDITY STUDY

The objective of this study was to validate reports on the bilateralit y status of breast cancer in first-degree relatives of women with a st rong family history of the disease; i.e., women with 1) two first-degr ee relatives who have, or have had, breast cancer; 2) one first- and o ne second-degree affected relative; or 3) one first-degree relative wi th diagnosis of breast cancer before the age of 50 years and/or bilate ral breast cancer. We were able to obtain hospital records for 94 affe cted relatives of 83 patients who agreed to participate in the study. The accounts of these women were compared to the bilaterality status i ndicated in the hospital records of the affected relatives. Inconsiste ncies that might have been attributed to incomplete medical records we re resolved through personal interviews with the participants, and whe n indicated, with other family members or the physician of the affecte d relative. Overall, 89.4% (84/94) of the reports validated in this ma nner were correct. Participants who reported unilateral breast cancer in a first-degree relative were correct 94.4% (68/72) of the time. Sim ilarly, 94.0% (47/50) of the accounts concerning affected living relat ives were accurate, regardless of whether the participant had indicate d unilateral or bilateral disease. However, participants who reported bilateral breast cancer in a deceased relative were accurate only 61.5 % (8/13) of the time. Incorrect reports were associated with misunders tanding of medical terminology, especially if the participant was youn g at the time of the diagnosis of her relative. (C) 1993 Wiley-Liss. I nc.