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FACSS · V MEETS IN
HISTORIC BOSTON
Fifth Annual Meeting Federation of Analytical Chemistry
and Spectroscopy Societies October 30 — November 3, 1978
Sheraton Boston Hotel Hynes Auditorium
Call for Papers Papers are invited in all areas of Analytical Chemistry and Spectroscopy. The deadline for titles and a 200-250 word abstract is May 1, 1978. Send to:
James F. Cosgrove Program Chairman, FACSS-78
GTE Laboratories Inc. 40 Sylvan Road
Waltham, MA 02154 ( 6 1 7 ) 8 9 0 - 8 4 6 0
General Information Contact
Arrangements Chairman Paul Lublin
GTE Laborator ies Inc. 40 Sylvan Road
Wal tham, MA 0 2 1 5 4 ( 6 1 7 ) 8 9 0 - 8 4 6 0
Scientific Program The scientific program will include papers in the following areas: Forensic Science; Thermoanalysis; Surface Analysis; Chromatography; GC/MS; Automation; Electron and Optical Microscopy; Electron and X-Ray Diffraction; Emission; X-Ray, Atomic and Acoustic Spectroscopy; Clinical; Chemical Institute Canada Symposium.
• Anachem Award • Benedetti Pichler Award
Instrument Exhibit A large Laboratory Equipment Exposition in the Hynes Auditorium will feature displays of the latest developments in analytical instruments.
Workshops Infra-Red Spectroscopy X-Ray Diffraction
Short Courses Modern Emission Spectroscopy Fourier Transform Spectroscopy Atomic Absorption Spectroscopy
Special Events at FACSS — 1978
• Mixer • Clambake • Spouses' Program
CIRCLE 79 ON READER SERVICE CARD
(7) Samples mus t be stable and capable of surviving the rigors of commercial t ransporta t ion.
(8) Reserve samples should be prepared and preserved to replace lost samples and to permit reanalysis of samples considered as outliers to att e m p t to discover the cause of abnormal results.
(9) The instructions mus t be clear. They should be reviewed by someone not connected with the s tudy to uncover potential misunders tandings and ambiguities.
(10) If the analyte is subject to change (e.g., bacterial levels, ni troglycerin tablets) , provision mus t be made for all par t ic ipants to begin the analysis a t the same t ime.
(11) Practice samples of a known and declared composition should be furnished with instructions not to analyze the unknowns unti l a specified degree of recovery and repeatabil i ty (or other a t t r ibute) has been achieved.
(12) Provision should be made when necessary for submission of s tandard curves, tracings of recorder charts , or photographs of thin-layer plates in order to assist in determining possible causes of error.
Other Types of Interlaboratory Studies
This type of collaborative study, which is designed to determine the characteristics of a method, must be carefully distinguished from other types of interlaboratory studies which by design or through ignorance provide other kinds of information. T h e most impor tan t types of other studies are:
(1) Those studies which require t h e collaborators to investigate the variability of par ts of methods or applicability to different types of samples. (An interlaboratory s tudy is usually an inefficient way of obtaining this type of information.)
(2) Those studies which permit an analyst to use any method he desires. Such studies invariably produce such a wide scatter of results t ha t the da ta are of little value for evaluation of methods. They may be useful in selecting a method from a number of apparent ly equivalent methods , provided the purpose is emphasized beforehand and the par t ic ipants provide a description of the method used in order to permit a correlation of the details of the methods with appa ren t biases and variabilities.
(3) Those studies which are used for quali ty control purposes, whose part icipants are not permi t ted sufficient t ime to gain familiarity with the method, or who permi t deviations to enter into the performance of the analyses on the grounds tha t the deviation is obviously an improvement which
could not possibly affect the results of the analysis, or who claim to have a superior method.
With this background information, it is now appropria te to introduce the following definitions which were agreed upon as par t of the guidelines for collaboration between the AOAC and the Collaborative Internat ional Pest icide Analytical Council Ltd. (CIPAC) (6).
Collaborative study. An analytical s tudy involving a number of laboratories analyzing the same sample(s) by the same method (s) for the purpose of validating the performance of the method (s).
Preliminary interlaboratory study. An analytical s tudy in which two or more laboratories evaluate a method to de termine if it is ready for a collaborative s tudy.
Laboratory performance check. T h e analysis of very carefully prepared and homogeneous samples, normally of known active ingredient content , to establish or verify the performance of a laboratory or analyst.
Summary T h e collaborative s tudy is an exper
iment designed to evaluate the performance of a method of analysis through the analysis of a number of identical samples by a number of different laboratories. With proper design, it provides an unbiased evaluation of the performance of a method in the hands of those analysts who will use it. A collaborative s tudy must be dist inguished from those studies designed to choose a method or to determine laboratory or analyst performance.
References (1) AOAC, "Handbook of the AOAC", 4th
éd., AOAC, Box 540, Benjamin Franklin Station, Washington, D.C. 20044, 1977.
(2) W. J. Youden, "Accuracy of Analytical Procedures", J. Assoc. Off. Anal. Chem., 45,169-73 (1962).
(3) Harold Egan, "Methods of Analysis; An Analysis of Methods", ibid., 60, 260-7 (1977).
(4) W. J. Youden and Ε. Η. Steiner, "Statistical Manual of the AOAC: Statistical Techniques for Collaborative Tests. Planning and Analysis of Results of Collaborative Tests", AOAC, Box 540, Benjamin Franklin Station, Washington, D.C. 20044,1975.
(5) W. J. Youden, "The Collaborative Test", J. Assoc. Off. Anal. Chem., 46, 55-62 (1963).
(6) "Guidelines for Collaboration Between the Association of Official Analytical Chemists (AOAC) and the Collaborative International Pesticide Analytical Council Ltd. (CIPAC)", ibid., 57,447-9 (1974).
Bibliography Daniel Banes, "The Collaborative Study
as a Scientific Concept", J. Assoc. Off. Anal. Chem., 52, 203-06 (1969).
William Horwitz, "Problems of Sampling and Analytical Methods", ibid., 59, 1197-203 (1976).
340 A · ANALYTICAL CHEMISTRY, VOL. 50, NO. 3, MARCH 1978