The long-term effect of external quality assessment on performance in service cytogenetics

Abstract

In 1993 a nationwide cytogenetic external quality assessment program (EQA) was initiated in the Federal Republic of Germany. Presently, some 70 laboratories, representing approximately 90% of all cytogenetic diagnostic tests, are participating in the study. Based on the quality assessment scheme of the Association of Clinical Cytogeneticists (1988) in the United Kingdom, quality of chromosome preparation and speed of routine diagnostic services are being evaluated. As a result of continuous external quality assessment, the mean banding level of participating laboratories rose from below 400 bands per haploid set (bphs) in 1994 to approximately 450 bphs in 1999 in prenatal tests and from about 400 to approximately 500 bphs in postnatal tests over the same 5-yr period. The percentage of participants achieving a banding level of 400 bphs or higher rose from approximately 50% to 93% in prenatal tests and from 60% to 96% in postnatal tests. No significant differences were observed in banding scores achieved by private laboratories compared to university institutes. The impact of the assessment of interpretation, reporting, and documentation remains difficult to evaluate. Preliminary data point to a more stringent adherence to ISCN nomenclature in karyotype designation by participants.

The Italian External Quality Assessment Scheme in Classical Cytogenetics: Four Years of Activity

“…The mean banding level in prenatal and postnatal tests of German laboratories rose over a 5-year period of continuous EQA [8]; a higher quality standard of UK prenatal cytogenetic services, reported by a UK National External Quality Assessment Scheme external audit (1987–1998), may have arisen in part as the result of participation of British laboratories in the EQA over a 10-year period [23]. In conclusion, our experience shows that participation in EQA programs is strongly recommended in order to standardize and assure quality in cytogenetic testing.…”

“…The scheme is both retrospective and prospective and covers constitutional and haematological diagnosis [7]. In 1993, a nationwide cytogenetic EQA program, based on the British scheme, was initiated in the Federal Republic of Germany [8]. In the last few years, Finland, France, The Netherlands and Spain have established EQA schemes in constitutional and/or oncological diagnosis [9].…”

20 Jahre externe Qualitätssicherung in der Zytogenetik

“…Das Projekt einer externen Qualitätssi-cherung wurde entsprechend den seinerzeit bestehenden Empfehlungen der Bundesärztekammer in 3 Phasen durchgeführt [6]. In Phase 1 wurden Informationen über die verschiedenen in der Routinediagnostik angewandten Techniken der Chromosomenpräparationen sowie der differenziellen Färbungen gesammelt.…”