What does semi-quantitative detection mean?

In general, semi-quantitative testing refers to a type of testing method used in medical diagnostics that provides information about the concentration range of a substance being tested, but does not provide an exact numerical value. A detailed explanation is as follows:

Semi-quantitative testing is a method that falls between qualitative and quantitative testing. It allows for a general estimation of the concentration range of the target substance in a sample, rather than providing a precise measurement. This type of test is conducted in situations where exact concentrations are unnecessary, and the main objective is to determine whether the substance's level is above or below a specific threshold—for example, checking whether food additives exceed safety limits or whether a substance in body fluids falls within a normal reference range. In such cases, semi-quantitative testing can meet the requirements while reducing testing costs and shortening testing time, thereby fulfilling the need for rapid screening.

When performing semi-quantitative testing, it is important to select test reagents or equipment that meet established standards to avoid inaccurate results due to equipment or reagent issues. Testing procedures must strictly follow the required protocols, as any deviation in the steps may lead to inaccurate results. If the test result is near the threshold or further confirmation is needed, a quantitative testing method should be used to obtain more precise data.