||Some people copy a questionnaire already used in other survey
' for the sake of comparability'. If the 2 questionnaires are applied to the same
population, different samples, then all is ok. But if the populations are different the comparability
is not assured.
Trans cultural differences, whether a question means the same to 2 different subjects,
exists not only between 2 cultures, but also between 2 cities in the same country.
Questionnaires must always be validated in the same population to which they are