Interaction between data collection and sample design: A plus in a complex selection process?

The purpose of the Quebec Health and Social Services User Satisfaction Survey was to provide estimates of user satisfaction for three types of health care institutions (hospitals, medical clinics and CLSCs). Since a user could have visited one, two or all three types, and since the questionnaire could cover only one type, a procedure was established to select the type of institution at random. The selection procedure, which required variable selection probabilities, was unusual in that it was adjusted during the collection process to adapt increasingly to regional disparities in the use of health and social services.