Abstract
The purpose of this analysis was to assess the validity of self-reported transfusion histories in dialysis patients. Using data from a cross-sectional study of a dialysis population being investigated for hepatitis C virus (HCV) infection, the correspondence between self-reported transfusion history and transfusion records was explored. Demographic data and dialysis histories were examined in relation to the accuracy of self-reports. Overall, the questionnaire data and the blood bank records agreed for 89% of participants. The Kappa statistic was 0.72 (95% CI: 0.61, 0.83) indicating an acceptable level of agreement. The effect of non-differential exposure misclassification on the risk estimates for transfusion history as a determinant of HCV infection is demonstrated. Exploring the discrepancies between self-reports and documented transfusion histories underlines the need to communicate clearly medical interventions in chronically ill patients. Additionally, it suggests that studies into transfusion-acquired blood-borne pathogens should use all available information sources to establish exposure.
Résumé
Cette analyse avait pour but d’évaluer la validité des antécédents auto-déclarés de transfusion chez les patients dialysés. À partir des données provenant d’une analyse transversale sur des patients dialysés pour détecter les cas d’infection au virus de l’hépatite C (VHC), on a étudié la correspondance entre les antécédents auto-déclarés de transfusion et les dossiers en attestant. Les données démographiques et les antécédents de dialyse ont été étudiés par rapport à l’exactitude des auto-déclarations. De façon générale, les données du questionnaire et les dossiers des banques de sang concordaient pour 89% des participants. Le résultat de l’analyse statistique Kappa était 0,72 (95% IC: 0,61 - 0,83) indiquant un niveau de concordance acceptable. On a démontré l’effet des erreurs de classification de l’exposition non différentielle sur les estimations du risque pour les antécédents de transfusion comme déterminant de l’infection au VHC. L’examen des disparités entre les auto-déclarations et les antécédents de transfusion documentés souligne la nécessité de communiquer les interventions médicales subies par des malades chroniques. En outre, cela suggère que les études faites sur les pathogènes à diffusion hématogène transmis par des transfusions devraient utiliser toutes les sources d’information disponibles pour établir l’exposition.
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