VARIABLES A variable is a characteristic or property that takes on different values in different persons, places or things. Variables are measurable by data. The variables determined may be for any study at any level, be it local, national, or international. In medical research, they assess changes in health or disease situations. Variables generally fall in one of two categories: 1. Qualitative (discrete) variables. 2. Quantitative (continuous) variables. 3. Hybrid variable.
Qualitative (categorical) variables Qualitative variables are variables where the magnitude or size of the characteristic or attribute as the same cannot be measured. They are classified by counting the number of people having or reporting the same characteristic or attribute, and not by measurement. In this case, there is only one variable: the number of people. Qualitative variables are discrete in nature, so they are sometimes referred to as discrete variables. Qualitative variables are typically used in clinical trials, usually to collect information on the action of the drug or its efficacy. They are also used in surveys, as part of pilot studies. Qualitative variables are particularly suited to gaining understanding of people‖s lived worlds, that is, how people experience and view, believe and think, aspire and assess the world about them. They may be used to generate hypotheses that can then be tested by other variables. Qualitative variables are also very vital in pilot studies and also may be used to collect data that help to interpret statistical material. Examples of qualitative variables are blood groups, the presence of disease, and the type of drug used to treat a disease. Blood group is a qualitative variable because it cannot be measured. Rather, it is classified into four groups: A, B, AB, or O.
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