How to write an introduction and methods of a systematic review of literature

Writing systematic review in English language is challenging for those whose first language is other than English and those who are not primarily trained on writing skill such as medical doctors.1 The guidelines to write and publish a systematic review are usually specific to scientific journals or such research groups that publish systematic reviews. Systematic reviews are accepted in most of the medical journals. The top 100 most cited systematic reviews in medical sciences research between 1977 and 2008 have mainly been published in Journal of American Medical Association (JAMA), British medical journal (BMJ) and the Lancet.