Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Recommendations for setting a criterion and assessing commutability of sample materials used in external quality assessment/proficiency testing schemes: Page feedback

Required* Indicates required field
Was this page helpful?
Please do not put Personal Identifiable Information (PII) in this field.
CAPTCHA
Enter the characters shown in the image.
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Was this page helpful?