الفهرس 
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Abstract
Most tests in the toxicology laboratory are directed toward the identification and/or quantitation of drugs and poisons. The primary techniques used include spot tests, spectrochemical tests, immunoassays and chromatographic techniques. Mass spectrometry may also be used, usually in conjunction with gas chromatography or liquid chromatography. Other methodologies include ion-selective electrode measurements of lithium, atomic absorption spectroscopy or inductively coupled plasma mass spectroscopy for lithium and heavy metals, and anodic stripping methods for heavy metals. The interassay imprecision for quantitative serum assays that are used in emergency toxicology is generally less than 5%. Not only must serum quantitation techniques be adequately precise to recognisze a change occurring from one time point to another, but they should also be accurate (i.e., near to a true value) so that management decisions may be made relative to predetermined decision values. The accuracy and interlaboratory variability of quantitative serum measurements may be assessed on the basis of results from proficiency testing programs. In general, accuracy and agreement of results obtained by different laboratories are favourable for drugs measured commonly and by uniform techniques (e.g., antiepileptic drugs). For drugs that are measured infrequently and by more diverse methods, the results obtained are more diverse. Currently, interlaboratory coeffecients of variation less than 8% and biases less than 15% have been demonstrated for the quentitation of most therapeutic drug monitoring-type drugs.