関連ワード:  which is the primary source of data    which is the primary source of data collection    which is not the primary source of data collection    which is the main source of primary data    which is the main source of collection of primary data    which is the source of primary data in research    which of the following is the primary source of data    which of the following is the primary source of data collection    which is the primary source of health care statistical data    which is a primary source of demographic data for a community