BACKGROUND Many laboratories use 4 delta check methods: delta difference, delta percent change, rate difference, and rate percent change. However, guidelines regarding decision criteria for selecting delta check methods have not yet been provided. We present new decision criteria for selecting delta check methods for each clinical chemistry test item. METHODS We collected 811,920 and 669,750 ...

Key comparisons carried out by the Consultative Committees (CCs) of the International Committee of Weights and Measures (CIPM) or the Bureau International des Poids et Mesures (BIPM) are referred to as CIPM key comparisons. The outputs of a statistical analysis of the data from a CIPM key comparison are the key comparison reference value, the degrees of equivalence, and their associated uncerta...

increase our understanding of this topic, it would be desirable to have a single equation. My suggestion would be that, at some future date, those two groups of authors combine their data in order to produce such an equation. Despite the discrepancies between the two studies cited above, we congratulate both groups of authors for taking the initiative to research a topic of great interest to pu...

the distribution of total plasma homocysteine concentrations in relation to the sex and age is described, in a population of shiraz, south west of iran and compared to those reported in other populations.  two hundred and one healthy males and 201 healthy females aged >15 y were randomly selected.  total plasma homocysteine concentrations were measured using high performance liquid chromatograp...

background: organic acids refer to a family of compounds that are intermediates in a variety of metabolic pathways. many organic acids are present in urine from clinically normal individuals. elevated levels of urine organic acids cause to the organic acidurias, disorders in which some metabolic pathways in organic acid metabolism are blocked. the present work identified major and minor urinary...

recognized as a reliable tool for assessing the hypothalamus-pituitary-adrenal (hpa) axis, measurement of salivary cortisol plays an important role in both the clinical and research settings. to establish a normative data, which forms the basis for the usage of this valuable parameter, we gathered 8:00 h saliva samples from 94 healthy individuals aged 6-14 years. cortisol levels were measured b...

A normal paediatric range of plasma alpha-amylase activity was determined using the Phadebas blue starch method. The range for children over one year was 98--405 IU/l. Plasma amylase activity increased throughout infancy. Mature levels of activity were observed in some children by age 2 months and in most of them by 9 months.