Systematic Literature Review

Over the past few years, the number of studies conducted and published in the medical sciences has grown exponentially. As a result, a systematic review of interventional trials is one of the best methods for gaining information about which new drugs, medical devices, and treatment protocols are effective. A systematic literature review is part of the Health Economics and Outcomes Research (HEOR)

What is a Systematic Literature Review?

A systematic literature review is a type of scientific work that consists of examining studies. In this work, the researcher tries to gather all the data about the scientific research that has been done on a certain topic. The result of a systematic literature review is to summarize, analyze and critically evaluate relevant scientific information, and answer the main question of the researcher (research team), which was the reason for conducting such work.

Systematic Review & Meta-Analysis: What’s their Relationship and Difference?

The two terms are related, and both describe the process of studying data, so they are often confused. Nevertheless, they are completely different types of work, with different objectives and methodologies.

Meta-analysis is a method of statistical analysis, which is the quantitative integration and evaluation of the results of different but similar studies. The main purpose of meta-analysis is to integrate data from different, independent studies, group them together, and determine a general trend.

In a systematic review, the researcher tries to find an answer to a specific question, which is the main purpose of the study. In doing so, he or she uses precise, pre-planned methods of selecting, evaluating, and analyzing scholarly articles. Meta-analysis can be one method for quantitatively synthesizing the results of individual scientific papers on an issue of interest and obtaining a summary assessment.

Systematic Review in Health Care

Systematic reviews of health-related scientific articles are an important source of reliable information. This research method provides verified evidence for each specific problem with accurate and standardized methods for selecting and evaluating papers related to various health interventions.

Who uses systematic reviews of medical articles and for what purpose:

  • health care decision-makers – to learn about the benefits and possible implications of new drugs and procedures in the licensure process;
  • clinicians – to incorporate the results of their own research into daily practice;
  • patients – to make informed decisions about treatment for themselves or loved ones;
  • medical professional communities – when developing clinical practice guidelines.

The main advantage of a systematic review is that it gives the most unambiguous answer to the posed clinical question. At the same time, the methods used in the review process minimize the possibility of systematic error.

Objectives and Principles of Systematic Literature Review

In health care, a systematic literature review is usually initiated by a panel of experts. Such a review is necessary for two instances:

  1. When one wants to find out whether a particular drug or procedure is effective for a particular medical problem, experts review the results of a particular drug or treatment protocol for different populations to accomplish this task.
  2. When one wants to find out if there is any way to solve a particular medical problem for a particular patient group. This task is accomplished by reviewing all currently available methods for solving the designated problem.

Principles of conducting a systematic review:

  • formulation of the goal – unambiguous;
  • choice of methodology – standardized and reproducible;
  • selection of studies that meet the criteria for acceptability – as much as possible.

Also, mandatory procedures are the evaluation of the reliability of the studies included in the review and the systematization of the results obtained.

Stages of writing a systematic review

Today, such work can be entrusted to consulting companies that specialize in health care. Typically, this process involves several steps:

  1. Formulating the question, which will be the purpose of the study.
  2. Forming a team of staff who will work on the review.
  3. Developing a research protocol, which should include details such as:
    • the purpose of the project;
    • the methods and processes to be used;
    • the eligibility criteria for selecting research articles;
    • what method will be used to extract data from scientific papers;
    • how the validity of the results will be analyzed.
  1. A literature search that is relevant to the research topic.
  2. Screening and evaluating studies that meet the eligibility criteria.
  3. Data extraction and analysis.
  4. Interpretation of results.

Modern technology makes it possible to present rather lengthy and detailed systematic reviews in a more concise and visual form. They can also be regularly updated to reflect new, more current research.