Blind Proficiency Test
Definition
A proficiency exercise in which the test materials enter the laboratory as apparent casework and the examiner does not know they are being evaluated. Better reflects actual casework performance than open tests because the examiner's normal workflow is not altered by awareness of being observed.
- Discipline
- Forensic laboratory quality assurance
- Key feature
- Examiner unaware the sample is a test, not real casework
- Compares against
- Open (declared) proficiency test
- Standards context
- ISO 17025, ASCLD-LAB, NABL accreditation programmes
Common questions
Why is a blind proficiency test considered more reliable than an open one?+
When an examiner knows a sample is a test, awareness of being evaluated can prompt extra care that does not reflect routine casework behaviour. A blind test enters the normal case queue, so it measures the examiner's actual day-to-day performance rather than their best-effort performance under observation.
What practical difficulties limit how often labs run blind proficiency tests?+
Blind tests require fabricating realistic case submissions, including plausible chain-of-custody paperwork and case context, without staff knowing which submissions are genuine. This is logistically demanding and costly compared to declared testing, which is why most accreditation schemes rely mainly on open proficiency tests supplemented with occasional blind ones.
Related terms
- ANAB
- The American National Standards Institute National Accreditation Board, formed after the merger of ASCLD-LAB with ANSI-ASQ National Accreditation Board in 2016. Now...
- ASCLD-LAB Legacy Programme
- The American Society of Crime Laboratory Directors Laboratory Accreditation Board's original forensic-specific accreditation programme, which ran alongside and was eventually superseded by...
- CTS (Collaborative Testing Services)
- A Herndon, Virginia-based proficiency testing provider offering fire debris analysis and explosives proficiency schemes. CTS distributes evidence-can samples containing burned substrate with...
- Document Control
- The systematic management of all procedural documents in a quality management system, ensuring that the current approved version is in use, all...
- Forensic Science Regulator Act 2021
- UK legislation that gave the Forensic Science Regulator statutory power to require compliance with quality standards, investigate non-compliant providers, and publish compliance...
- ISO/IEC 17025
- The international standard for testing and calibration laboratories, published jointly by the International Organization for Standardization and the International Electrotechnical Commission. It...
- NABL T-126
- Technical Requirement T-126 issued by India's National Accreditation Board for Testing and Calibration Laboratories: the discipline-specific criteria for forensic science laboratories, covering...
- Open Proficiency Test
- A proficiency exercise in which the examiner knows they are being tested. Measures the laboratory's capability under conditions of heightened attention but...
- UKAS
- United Kingdom Accreditation Service; the sole national accreditation body for the UK and ILAC MRA signatory. Accredits forensic science providers under ISO/IEC...