Using a thyroid disease-free population to define the reference interval for TSH and free T4 on the Abbott Architect analyser.

Objective: Thyroid disease can be subtle in its presentation, and TSH reference intervals may be artefactually increased by including persons with subclinical thyroid disease. We have therefore used a thyroid disease-free population to determine TSH and fT4 reference intervals.

Design: Apparently healthy subjects were assessed by health questionnaire, drug history, clinical assessment and measurement of thyroid antibodies.

Harmonising adult and paediatric reference intervals in australia and new zealand: an evidence-based approach for establishing a first panel of chemistry analytes.

Scientific evidence supports the use of common reference intervals (RIs) for many general chemistry analytes, in particular those with sound calibration and traceability in place. Already the Nordic countries and United Kingdom have largely achieved harmonised RIs. Following a series of workshops organised by the Australasian Association of Clinical Biochemists (AACB) between 2012 and 2014 at which an evidence-based approach for determination of common intervals was developed, pathology organisations in Australia and New Zealand have reached a scientific consensus on what adult and paediatric intervals we should use across Australasia.

Bias Assessment of General Chemistry Analytes using Commutable Samples.

Harmonisation of reference intervals for routine general chemistry analytes has been a goal for many years. Analytical bias may prevent this harmonisation. To determine if analytical bias is present when comparing methods, the use of commutable samples, or samples that have the same properties as the clinical samples routinely analysed, should be used as reference samples to eliminate the possibility of matrix effect.

Evidence-based approach to harmonised reference intervals.

Although we are in the era of evidence-based medicine, there is still a substantial gap between theory and current practice with the application of reference intervals as decision making tools. Different laboratories may have different reference intervals for the same tests using the same analytical methods and platforms. These differences have the potential to confuse physicians making the assessment and monitoring of patients more difficult by providing discordant information.

Implementation of the HbA1c IFCC unit --from the laboratory to the consumer: The New Zealand experience.

In 2007, an international consensus statement recommended that HbA1c results should be reported world-wide in IFCC units (mmol/mol) and also the more familiar derived percentage units using a master equation. In New Zealand, the HbA1c IFCC units have been successfully implemented and used exclusively since 3rd October 2011 (following a 2 year period of reporting both units) for both patient monitoring and the diagnosis of diabetes, with a diagnostic cut-off of ≥50 mmol/mol. The consultation process in New Zealand dates back to 2003, well before the international recommendations were made.

Cross-reactivities of macroprolactin and big-prolactin in three commercial immunoassays for prolactin: a chromatographic analysis.

Objectives: To compare the recently released Elecsys Prolactin II with the Access and Centaur assays for reactivity with macroPRL, bigPRL and monomeric PRL in samples fractionated using gel filtration chromatography (GFC).

Methods: Prolactin (PRL) concentration was measured before (total PRL) and after GFC over Superdex 75 (n=16-18) using prolactin assays on the Access2 (Beckman Coulter Inc.) and Centaur (Siemens Medical Solutions Diagnostics) analyzers and the Prolactin II assay (Roche Diagnostics) on the Elecsys 2010 analyzer.