短期雇用の従業員は情報セキュリティ上のリスク要素？

下記の記事が出ている。

　The Risks of Hiring Temps: Over a Third of U.S. Retailers Don't Know Which Systems Their Temporary Workers Have Accessed
　eSecurity Planet: December 8, 2015
　http://www.esecurityplanet.com/network-security/the-risks-of-hiring-temps-over-a-third-of-u.s.-retailers-dont-know-which-systems-their-temporary-workers-have-accessed.html