Design of survey instruments

Scope of this chapter In this chapter, the various aspects of the design of a survey instrument are considered. Designing a survey instrument is a complex process and cannot be considered in isolation from other aspects of the overall design of the survey. For example, the decision as to the survey methodology impacts directly on the design of the survey instrument. It is also important to realise that some surveys may use multiple instruments. For example, in surveys that are focused on households and individuals, it may be necessary and desirable to provide an instrument for the household as a whole, and individual instruments for each individual within the household. In household travel surveys, there are usually four different instruments: a form for recording data about the household, a form for each individual in the household, a form for the vehicles available for use by household members, and a daily diary for each household member, in which they record details of their travel. A similar set of survey instruments is also often used in time use surveys, except that there is less interest in household vehicles, so information about them may be collected on the household survey form. For time use surveys, the diary will collect information about what the person is doing throughout the day or days of the survey.