Lh. Elvers et Jg. Loeber, THE NEED FOR STANDARDIZED BLOODSPOT TSH-CALIBRATORS IN CONGENITAL HYPOTHYROIDISM SCREENING, Early human development, 45(1-2), 1996, pp. 179-190
Introduction: The preparation of bloodspot calibrators and quality con
trol samples for neonatal thyrotropin (TSH), as part of the national q
uality assessment scheme in The Netherlands, is sometimes problematic.
Often, the recovery of the added TSH is well above 100% when measured
in plasma. Results from other External Quality Assessment Schemes for
neonatal TSH show similar problems. Methods and Results: A questionna
ire was sent to 17 kit manufacturers and organizers of EQAS concerning
the preparation of bloodspot calibrators for TSH; 13 completed questi
onnaires were returned. There are large differences with respect to ty
pe of filterpaper, matrix, assessment of TSH-concentrations to the cal
ibrators, size of the bloodspots, shelf life, etc. Discussion: Attenti
on is focused on several items to be considered when attempting standa
rdization of the preparation of TSH bloodspot calibrators.