“…Five case-control [13,14,18,19,25] and eight cohort studies [[15], [16], [17],[20], [21], [22], [23], [24]]. The included studies were published between 1994 to 2016 and originated from different parts of the world including; Australia, China, Finland, India, Mexico, Saudi Arabia, Sweden, Switzerland, United Kingdom and The United States of America.…”