Importance of design in descriptive studies

Descriptive studies differ from exploratory studies in the formality with which they are designed. Exploratory studies are characterized by flexibility, while descriptive studies attempt to obtain a complete and accurate description of a situation. Formal design is required to ensure that the description covers all phases desired. Precise statement of the problem indicates what information is required. The study must then be designed to provide for the collection of this information. Unless the study design provides specified methods for selecting sources of information (sample design) and for collecting data from those sources, the information obtained may be inaccurate or inappropriate. Formal design is also required to forestall collection of unnecessary data. Since descriptive studies often cost many thousands of dollars, the unnecessary expenditure could be large. Descriptive data are commonly used as direct bases for marketing decisions. After analyzing the data, the investigators attempt to predict the result of certain actions – for example, they may predict that concentration of advertising on upper-income people will increase sales volume.