How to develop and validate a questionnaire for orthodontic research

The use of psychometric tools to assess various psychological aspects of malocclusion and treatment is increasing in orthodontics. Mere evaluation of an orthodontic patient with normative criteria is not enough; instead, the psychological status should be assessed using a questionnaire. Many generic and few condition-specific tools are available for assessing quality of life (QoL) in orthodontics. The steps involved in the development of such tools are complex and unknown to many. This article outlines the methodology involved in the development and validation of a psychometric tool for dental and orthodontic use. It also helps the clinician to translate and cross-culturally adapt an existing QoL tool to a different setting.