External quality control for embryology laboratories De Assin, R Gonzalvo, MC Clavero, A Ramirez, JP Vergara, F Martinez, L Castilla Alcalá, José Antonio embryology embryo quality quality control Participation in external quality control (EQC) programmes is recommended by various scientific societies. Results from an EQC programme for embryology laboratories are presented. This 5-year programme consisted of the annual delivery of (i) materials to test toxicity and (ii) a DVD/CD-ROM with images of zygotes and embryos on days 2 and 3, on the basis of which the participants were asked to judge the embryo quality and to take a clinical decision. A high degree of agreement was considered achieved when over 75% of the laboratories produced similar classifications. With respect to the materials analysed, the specificity was 68% and the sensitivity was 83%. Concerning embryo classification, the proportion of embryos on which a high degree of agreement was achieved increased during this period from 35% to 55%. No improvement was observed in the degree of agreement on the clinical decision to be taken. Day-3 embryos produced a higher degree of agreement (58%) than did day-2 embryos (32%) (P<0.05). Participation in EQC increased the degree of inter-laboratory agreement on embryo classification, but not the corresponding agreement on clinical decision taking. It is necessary to introduce measures aimed at standardizing decision taking procedures in embryology laboratories. 2025-01-20T08:35:05Z 2025-01-20T08:35:05Z 2010 journal article Castilla JA, Ruiz de Assín R, Gonzalvo MC, Clavero A, Ramírez JP, Vergara F, Martínez L. External quality control for embryology laboratories. Reprod Biomed Online. 2010 Jan;20(1):68-74. PMID: 20158990 https://hdl.handle.net/10481/99624 10.1016/j.rbmo.2009.09.033 eng open access Elsevier