Final answer:
Urinalysis is the preferred method of drug testing by employers due to its non-invasive nature, ease of administration, and quick results. It is also a cost-effective choice for mass screenings.
Step-by-step explanation:
The preferred method of drug testing by employers is urinalysis. A urinalysis is a routine test performed to analyze a urine sample. This simple test can reveal various health conditions and can be used to monitor certain diseases. Urinalysis involves physical, chemical, and microscopic examinations of the urine, and it can detect the presence of substances such as protein, glucose, and bacteria, which can indicate different health issues or substance use.
Employers often favor urinalysis due to its non-invasive nature, ease of administration, and the rapid availability of results.
It is also a cost-effective method for mass screening. While blood, hair, and impairment tests are also possible drug testing methods, they are less commonly used for routine employer drug screenings. Blood sampling can be more invasive, hair sampling may provide longer detection periods but is more expensive, and impairment tests are not as widely accepted or standardized.