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.   

1.
Association of Clinical Cytogeneticists UK NEQAS: Guidelines for Clinical Cytogenetics (Royal Institute of Public Health and Hygiene, 1994).
2.
American College of Medical Genetics Laboratory Practice Committee: Standards and Guidelines: Clinical Genetics Laboratories (American College of Medical Genetics, 1993).
3.
Berufsverband Medizinische Genetik: Richtlinien zur Durchführung zytogenetischer Diagnostik. Med Genetik 2/4:6 (1990).
4.
EUCROMIC Quality Assessment Group: Quality Guidelines and Standards for Genetic Laboratories/Clinics in Prenatal Diagnosis on Fetal Samples Obtained by Invasive Procedure. Eur J hum Genet 5:342–350 (1997).
5.
Held KR: Karyotyping and data interpretation, in Wegner RD (ed): Diagnostic Cytogenetics, pp 75–96 (Springer-Verlag, Berlin 1999).
6.
Held KR, Eiben B, Miny P: Longtime effect of cytogenetic external quality assessment. Cytogenet Cell Genet 85:23 (1999).
7.
Hsu LYF, Kaffe S, Jenkins EC, Alonso L, Benn PA, David K, Hirschhorn K, Lieber E, Shanske A, Shapiro LR, Schutta E, Warburton D: Proposed guidelines for diagnosis of chromosome mosaicism in amniocytes based on data derived from chromosome mosaicism and pseudomosaicism studies. Prenat Diagn 12:555–573 (1992).
8.
Knutsen T, Bixenman HA, Lawce H, Martin PK: Chromosome analysis guidelines: preliminary report. Cytogenet Cell Genet 44:1–4 (1990).
9.
United Kingdom External Quality Assessment Scheme: Slide Assessment Scoring Guide. Edinburgh. ACC Clin Cytogenet Bull 2:35–26 (1988).
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