What characterizes a clean catch specimen?

A clean catch specimen is specifically designed to provide a urine sample that is free from contamination, which is why it is characterized by collecting urine after the genitals have been cleaned. This process helps to minimize the presence of bacteria or other substances that may interfere with the test results. Additionally, omitting the first and last portions of the urine stream is crucial, as it ensures that any contaminants in the urethra are not included in the sample, thus enhancing the accuracy of the results.

The other characteristics of clean catch specimens, such as refrigeration, timing of collection, or including all urine passed, do not apply here. For instance, immediate refrigeration is not a requirement for clean catch samples unless stated otherwise by specific testing protocols. Clean catch specimens can be collected at various times of the day, not strictly in the morning, and including all urine passed would defeat the purpose of the clean catch method, which aims to reduce contamination from the urinary tract.