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Laboratory and Instrument Quality Control

  • Derek Pearson
  • Nigel Lawson

Abstract

Clinical trials now run for many years. Sponsors need assurance that the instruments they use remain stable over that length of time and report consistent results. It is important, however, to clarify the difference between quality assurance (QA) and quality control (QC). During any process, there should be ongoing process control. This is usually an automatic feedback situation. Quality control is the ongoing sampling of the process being evaluated. This allows for change in the process, but not normally immediately, unless sampling and analysis is rapid. Quality assurance is the evaluation of the quality control process or audit. It is normally conducted periodically and is a sampling process of the quality control process to ensure the described checks are being conducted. For example, in a manufacturing line where, say, washers are being made, the mean weight of the washers being produced may be evaluated. If the average weight of the washers varies beyond predetermined limits, the mix may be adjusted to keep the washers within basic limits. For every one hundred washers made, one will be taken and carefully measured. If the washer is outside predefined limits, then the manufacturing process may be adjusted and if necessary stopped and restarted, to ensure the washers are made to specification (quality control). Periodically an audit will be made of the whole process to ensure everything was conducted to all the written specifications (quality assurance). Quality control is the remit of the local investigator and quality assurance may form part of the audit carried out by the CRO, QA center or trial sponsor.

Keywords

Control Chart Quality Control Data CUSUM Chart Quality Control Process Phantom Data 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag London 2002

Authors and Affiliations

  • Derek Pearson
  • Nigel Lawson

There are no affiliations available

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