Bettany-Saltikov (2012) describes a Systematic Review as:
"... a summary of the research literature that is focused on a single question. It is conducted in a manner that tries to identify, select, appraise and synthesize all high quality research evidence relevant to that question. High quality research includes those studies with an explicit and rigorous design that allow the findings to be interrogated against clear contexts and research intentions." (p. 5) Bettany-Saltikov, J. (2012).
An outline of the similarities and differences between systematic and literature reviews can be found in Table 1 (p. 49) of the following journal article.