This is Linköping university library’s guide to systematic literature reviews. Scientific literature reviews are generally aimed at providing an idea of what has already been written in a field of research, which research methods have been used, which theories have been developed in relation to observations carried out or which practical applications may be demonstrated with regard to research results – especially within medical research.

A literature review can be conducted in a variety of contexts such as

  • in the introduction to a research article, paper, or dissertation to present previous research in a research area,
  • in the research grant application to demonstrate gaps in knowledge in a research area,
  • in a stand-alone review on the knowledge base of a research area
  • in the research for an evidence-based policy document


Types of reviews

Two main categories of literature reviews may be distinguished:

  • The traditional literature review may look different from time to time and is based on structured literature searches. It has many varieties and come with different terminologies.
  • The systematic literature review is aimed at an even more systematic and far-reaching search based on a specific research question in order to identify the majority of relevant studies and to critically assess and synthesize the results of these studies according to predefined criteria. It also has several varieties of quantitative or statistical analysis, often called meta-analysis.

The table below presents a comparison of the traditional and systematic review method.

Traditional review

Systematic review


Descriptive study to achieve broad understanding

Specified aim and review question, clearly delimited objectives. 


Big picture

Narrow focus

Planning the review

No defined method of approach, allows for creativity and exploration

Transparent  process and documented audit trail

Identifying studies

Searching is probing, moving from one study to another, following up leads, ad hoc.

Rigorous and comprehensive search for as many relevant studies as possible

Selection of studies

Purposive and goal-oriented selection on the part of the reviewer

Predetermined criteria for including and excluding studies

Quality assessment

Based on the reviewer's judgment

Checklists to assess the methodological quality of studies

Analysis and synthesis


Short tabular summaries

Methodological report

Not necessary

Precondition for transparency

Source: Karolinska University Library (2021), with reference to Jesson, Matheson & Lacey, 2011.

Search support for researchers

LiU researchers and PhD students can consult a librarian, for example when doing a literature review for a dissertation or a systematic review. Together we will look at your specific research questions and discuss topics such as:

  • selecting databases and search tools
  • selecting keywords
  • constructing search strings
  • documenting searches
  • managing search results

Make an appointment by completing this form:

Search support for researchers