A practical guide to surveys and questionnaires.

Surveys with questionnaires play a vital role in decision and policy making in society. Within medicine, including otolaryngology, surveys with questionnaires may be the only method for gathering data on rare or unusual events. In addition, questionnaires can be developed and validated to be used as outcome measures in clinical trials and other clinical research architecture. Consequently, it is fundamentally important that such tools be properly developed and validated. Just asking questions that have not gone through rigorous design and development may be misleading and unfair at best; at worst, they can result in under- or overtreatment and unnecessary expense. Furthermore, it is important that consumers of the data produced by these instruments understand the principles of questionnaire design to interpret results in an optimal and meaningful way. This article presents a practical guide for understanding the methodologies of survey and questionnaire design, including the concepts of validity and reliability, how surveys are administered and implemented, and, finally, biases and pitfalls of surveys.