Because although the study participants had been domiciled in other provinces from the qualifying criteria for research participants must live in an area of not less than 5 years.
Because, although participants have come from other provinces, but not domiciled in the selection criteria, participants must live in an area not less than 5 years.
Because, even though research participants will ever resided from other provinces, but the criteria for selecting research participants have to live in the area of not less than 5 years.