Annette, Giangiacomo and Coleman, Anne. The Epidemiology of Glaucoma. 2009. Springer Journal. Web. Nov. 5 2013. http:/www.springer.com/cda/content/document/cda_downloaddocument/9783540694724-c1.pdf%3FSGWID%3D0-0-45-646107-p173833724+&cd=3&hl=en&ct=clnk&gl=us Glaucoma is the second leading cause of blindness in the world. Written in the study estimated by 2010 there will be 60.5 million people in the world with open-angle glaucoma and angle- closure glaucoma. The difference between open and closed glaucoma is the angle between the iris and the cornea. Risk factors for open angle glaucoma are increased age, African ethnicity, and decreased corneal thickness. The risk factors for closed glaucoma are female, Asian or Inuit ethnicity, and steep corneal curvature. Population-based screening for open-angle glaucoma is not recommended. Screening for angle-closure may be feasible. This study is an example of the facts an epidemiologist would need base his or her opinion on how to prevent this disease globally.