I am writing a questionnaire in ASP .NET MVC. The format of the questionnaire is one yes/no question per page. The questionnaire is a safety questionnaire where, for the majority of the time the user will answer no to the questions. Should I set the default state of the radio buttons to 'no' to save the majority of the users time (enhancing the user experience) or should I leave them both as unselected so as not to potentially skew the results as a result of users' laziness?
Since it is a survey, I'd would not set the default state and make all of the questions required (validating on submit and displaying an error message for skipped questions). That way you are forcing the user to make a decision and not skewing the results.