Qualitative: Qualitative tests are used to determine what is present in a sample. A sample of paint, for example, may be tested for traces of lead ions.
Quality Assurance: All the planned and systematic activities implemented within the quality system, and demonstrated as needed, to provide adequate confidence that an entity will fulfil requirements for quality (AS/NZS ISO 8402:1994).
Quantitative : Quantitative tests are used to determine how much of a particular chemical is present in a sample. A sample of blood, for example, may be tested to determine the amount of alcohol present.