Do items need to be cleaned before they are sterilized, but they do need to be cleaned before they are disinfected?

The answer to this is incorrect. Items do need to be cleaned prior to disinfection.

Direct from the IAHCSMM Central Service Technical Manual:
"Thorough cleaning of items is the first and most important step in any sterilization or high-level disinfection process. Organic matter (soil) such as serum, blood, pus, and fecal material can dilute or inactivate the active ingredient in a liquid disinfectant. It can also hinder the contact of the disinfectant's ingredients with microorganisms on the surface of the device. Therefore, items should be cleaned until no visible tissue residue, fluid, or soil remains on them."

John failed his CRCST exam. Anybody taking this practice exam would do well to double-check every question before committing these answers to memory. This is NOT the only incorrect answer on this exam.