When it comes to getting a lot of information in a short period, a questionnaire may be the answer. Questionnaires contain lists of questions in open-ended or closed-ended formats. While it takes time ...

Background: Reliability or validity studies are important for the evaluation of measurement error in dietary assessment methods. An approach to validation known as ...

Background The Oslo Sports Trauma Research Center questionnaire on Health problems, recently updated to a second version (OSTRC-H2), has shown a greater ability than a traditional surveillance method ...

Here at Pew Research Center, we are often asked about how we conduct our research. We work hard to make our methodologies transparent and understandable, but we also know that survey mode effects and ...