Pre-analysis includes all steps from the patient to the analytical measurement.

Errors in this phase are among the most frequent causes of deviating laboratory results.

Typical sources of error

• Incorrect sample type or sampling time
• Inadequate labelling or storage
• Incorrect transport conditions (temperature, delay)
• Influence of diet, medication or body position

How can they be avoided?

• Standardised work instructions and employee training
• Correct time and temperature control
• Pre-analytical checklists and validation of transport routes

Good pre-analysis is crucial for the reliability of the subsequent laboratory analysis – and the basis for correctly evaluated proficiency test results.