Development, validity and reliability of a postal questionnaire assessing health states relevant to young persons with stroke in Sweden.

Purpose. The aim was to develop and test a postal questionnaire, the Swedish MYS questionnaire, for validity and reliability in order to survey health states relevant to young persons with stroke. Method. The questionnaire was designed with the International Classification of Functioning, Disability and Health as a frame and tested for content validity, face validity and readability by a group of experts including an occupational therapist, a physician, a physiotherapist, a psychologist, a speech and language therapist, a welfare officer and a selected sample of young persons with stroke (n = 15). To test the questionnaire for reliability in terms of stability a test-retest was performed on a selected sample of young persons (n = 20) with stroke. Results. The questionnaire was found to be valid in terms of content validity, face validity and readability and finally consisted of 59 questions encompassing health states relevant to young persons with stroke. The questionnaire was stable in the test-retest (kappa; 0.40-1.0) except for two questions and one alternative answer. Conclusion. The Swedish MYS questionnaire is a valid and reliable questionnaire that can be used in postal surveys of young persons with stroke except for two questions and one answering alternative, which need to be tested further.