Participants completed a confidential questionnaire, which was then placed in a sealed envelope.
A copy of the questionnaire, which was sent to more than 30 manufacturers three weeks ago, was obtained by The New York Times.
To answer this question we designed a questionnaire, which was validated in two different tertiary headache centres.
Each student questionnaire corresponded to one parental questionnaire, which was brought home for their guardians to complete.
A similar approach was followed for the Turkish questionnaire, which was also finalized based on the views of three academicians.
The characteristics of headache were collected by a questionnaire, which was administered by one of the authors.
The SF-36 Health Survey and the Quality of Life Questionnaire, which was designed for this study, were used.
The teacher candidates evaluated the questionnaire which was designed according to instructional multimedia materials developed by them in PBL.
It took 10 minutes to administer the questionnaire which was in the English language.
Each family received one questionnaire, which was completed at home.
We developed a survey questionnaire, which was pretested on respondents.
