Standards for microbiology investigations (UK SMI)

UK Standards for Microbiology Investigations (UK SMIs) are a comprehensive referenced collection of recommended algorithms and procedures for clinical microbiology.

This collection was withdrawn on

This content now available at UK Standards for Microbiology Investigations.

UK Standards for Microbiology Investigations (UK SMIs) are now hosted on the Royal College of Pathologists (RCPath) website. Up-to-date information can be found at this location.

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UK SMI supporting information

UK SMI repository

The search strategy for any UK SMI document is available on request by emailing

UK Standards for microbiology investigations consultations

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These are bacteriology standards for the laboratory covering receipt of the sample in the laboratory to the issue of a report.


Virology and serology diagnostic algorithms and standards for the laboratory testing of viruses.


These documents cover techniques used for bacterial identification.

These standards describe essential laboratory practices to ensure quality like assay validation, quality assurance and understanding uncertainty of measurement.

National user manual and Syndromic algorithm

The national user manual template contains standard headings and suggestions to guide laboratories in completing a national user manual. Two worked examples of use have been developed and work on this has now been completed.

The syndromic algorithm documents provide the overarching framework for all other UK SMIs.

These standards help clinicians and diagnostic laboratory staff choose the correct approach for investigating a sample from a clinical setting.

Development of syndromic algorithms has now resumed. Documents that have exceeded their review date will remain on the website until they are superseded or withdrawn.

Test procedures

These standards outline the test procedures for identifying the organisms.

Withdrawn and recalled documents

Published 1 August 2014
Last updated 15 December 2021 + show all updates
  1. Updated UK SMI repository section.

  2. Removed 'report on survey into susceptibility testing methodology'.

  3. The standards for microbiology investigations (SMI): searchable index has been added.

  4. First published.