The Distinction Between a Literature Review and a Systematic Review

Abstract: The given text discusses the differences between a literature review and a systematic review. A literature review provides an overview of existing studies on a topic, describing, evaluating, and summarizing the current state of knowledge. It is a common component of research papers, theses, and grant proposals. In contrast, a systematic review takes a more analytical and scientific approach, providing a more comprehensive and robust summary of previous research. It is characterized by explicit, reproducible methods for each step of the review, including a precise review question, explicit inclusion and exclusion criteria, comprehensive search strategies, and careful screening and assessment of studies. Systematic reviews often involve meta-analysis and provide evidence-based conclusions that summarize the current state of knowledge. The key differences between the two types of reviews include scope, methodology, study selection, analysis, transparency, and objectivity. Understanding these differences allows researchers to select the most appropriate approach for their research goals and audience needs.

Introduction

Many students and researchers are confused about the differences between regular literature reviews and systematic reviews. Both types of review are used to synthesize previous research on a topic, but there are important distinctions in their methods and goals. In this post, I'll go over the key differences you need to understand.

What is a Literature Review?

A literature review provides an overview and summary of existing studies on a particular topic. The aim is to describe, evaluate, and summarize the current state of knowledge on that topic. Literature reviews are very common in research papers, theses, grant proposals, and more.

To conduct a literature review, the researcher searches for relevant articles, books, and other sources on a topic. Then they read and assess the sources to determine which are most relevant, reliable, and important to summarize. The sources are often described and analyzed to identify major themes, trends, theories, and findings in the existing literature.

The literature review writing is largely descriptive - the author summarizes each source and provides their own perspective or commentary on the topic's main ideas. The structure and scope of a literature review can vary greatly. Reviews can cover research from the past few years or several decades to show how knowledge has changed over time. There are no fixed rules on which or how many sources to include.

What is a Systematic Review?

A systematic review takes the literature review process a step further to provide a more comprehensive and robust summary of previous research. A systematic review takes an analytical, scientific approach to sourcing, appraising, and synthesizing studies on a clearly defined subject or question.

Systematic reviews specify explicit, reproducible methods for each step of the review. They start by identifying a precise review question and outline explicit inclusion or exclusion criteria for selecting studies. Comprehensive search strategies are used to find as much relevant research as possible. Multiple databases, grey literature, and other sources are systematically searched using precisely defined terms.

Studies are carefully screened and assessed for eligibility based on the pre-defined criteria. Full texts are evaluated to ensure they meet quality standards for scientific rigor and align with the research question. All steps of study selection are documented to ensure complete transparency and replicability.

Included studies are analyzed and compared in detail. Statistical methods like meta-analysis may be used to combine quantitative results. The authors work to synthesize all relevant data into evidence-based conclusions that summarize the current state of knowledge. The review methods and limitations are discussed to aid interpretation.

Key Differences:

- Scope - Literature reviews cover a broad topic area; systematic reviews address a narrowly focused research question.

- Methodology - Systematic reviews use rigorous, pre-defined, and reproducible methods for each step. Literature reviews use less formal methods.

- Study Selection - Systematic reviews apply precise eligibility criteria and document reasons for exclusion. Literature reviews may include biased selection of sources.

- Analysis - Systematic reviews often involve meta-analysis of data. Literature reviews use more qualitative and descriptive analysis.

- Transparency - Systematic reviews report full details of literature search and selection strategies. Literature reviews provide less documentation of methods.

- Objectivity - Systematic review conclusions are grounded in scientific analysis to minimize bias. Literature reviews can be more prone to author bias.

While both review types synthesize previous research, the formal methodology of a systematic review sets it apart from the traditional literature review. The systematic approach provides a higher level of evidence and confidence in the findings. But literature reviews still serve an important role in many contexts.

Recognizing the distinction permits researchers to choose the optimal method that aligns with their research objectives and cater to the requirements of their target audience. This knowledge enables researchers to discern when to undertake a thorough systematic review or a more casual literature review, depending on the demands of their project.

Conclusions

The main difference between a literature review and a systematic review is the level of formality and objectivity in their methods. A literature review provides a broad overview of existing studies on a topic, while a systematic review takes a more analytical and scientific approach, providing a more comprehensive and robust summary of previous research. Systematic reviews use explicit, reproducible methods for each step of the review, including a precise review question, explicit inclusion and exclusion criteria, comprehensive search strategies, and careful screening and assessment of studies. Systematic reviews often involve meta-analysis and provide evidence-based conclusions that summarize the current state of knowledge. The key differences between the two types of reviews include scope, methodology, study selection, analysis, transparency, and objectivity.

Understanding Oxidation Reactions in Chemistry

Oxidation reactions are an incredibly important reaction type in chemistry. They involve the transfer of electrons between substances, leading to changes in oxidation states of atoms. Understanding oxidation-reduction reactions is key for chemistry students.

In an oxidation reaction, a molecule, atom or ion loses electrons. This is known as oxidation. The oxidizing agent causes oxidation by taking electrons from another substance. Some common oxidizing agents include oxygen, halogens, sulphuric acid and permanganate ions. 

Let's look at the reaction between magnesium metal and oxygen gas as an example:

2Mg(s) + O2(g) → 2MgO(s)

In this reaction, magnesium metal is oxidized by oxygen gas. The magnesium atoms give up two electrons each to oxygen molecules. This causes the magnesium to increase in oxidation state from 0 to +2. Meanwhile, the oxygen gains electrons and is reduced.

Oxidation reactions result in a loss of electrons and an increase in oxidation state. Other signs of oxidation include:

- Gain of oxygen  

- Loss of hydrogen

- Gain of electronegativity

- Loss of electrons in bond rearrangement

Being able to identify oxidized and reduced species in a reaction is critical. Some tips include:

- Metals tend to get oxidized and nonmetals reduced

- Atoms that gain oxygen are oxidized

- Atoms that lose oxygen are reduced

- Atoms that gain electrons are reduced 

Common oxidizing agents to recognize include halogens, concentrated acids, oxygen, sulfur and permanganate compounds. Reducing agents provide electrons and include metals, hydrides and other electron-rich substances.

Oxidation reactions power many important chemical processes we rely on. From combustion engines to hand warmers, batteries and more, these reactions are at the heart of chemistry. Gaining a solid understanding of electron transfers in oxidation will serve any aspiring chemist well in grasping chemical reactivity.

10 Great Alternatives to PowerPoint for Making Presentations for Science

PowerPoint has long been the standard program for creating presentations in business and education. However, in recent years many new and innovative presentation tools have emerged as alternatives to the Microsoft staple. 

In this blog post, I'll highlight 10 solid PowerPoint alternatives worth checking out. Whether you're looking for new features, better design capabilities, more collaboration options or just a change of pace from PowerPoint, these presentation makers have got you covered.

1. Google Slides

As part of Google Workspace, Google Slides is a popular free option for basic presentation needs. It's easy to use, allows for real-time collaboration with others and integrates seamlessly with other Google services. The templates and design options are more limited compared to PowerPoint but it's a great simple alternative.

2. Canva

Canva offers an immense library of templates, photos, illustrations and design assets for creating sharp presentations quickly, even without prior design experience. It's also free to use with the option to upgrade for more functionality. The drag and drop editor couldn't be easier. 

3. Prezi

Prezi's zoomable canvas sets it apart from traditional slide-based tools. The nonlinear approach allows for more dynamic and interactive presentations. Though there's more of a learning curve and less structure than simple slides.

4. Keynote

Apple's sleek presentation software comes loaded on Macs and iOS devices. Built-in animations, themes and integration with other Apple apps make it an excellent alternative for Mac users. The learning curve is minimal for those with PowerPoint experience.

5. Zoho Show

For those seeking a free, web-based alternative, Zoho Show is a solid choice. With 200+ templates, collaboration capabilities, built-in image editor and ability to work offline, it offers an impressive free option.

6. Visme

Visme focuses more on creating infographics, diagrams, maps and other visual content to be used in presentations. It provides tons of data visualization options lacking in PowerPoint and is easy for anyone to create pro-level visuals.  

7. Slides

Slides from Google is a pared-down, web-based tool meant for quickly creating simple slide decks. The formats and options are limited but if you need to make a fast presentation without the bells and whistles, Slides is handy.

8. Sway

Microsoft's own PowerPoint alternative, Sway, is centered around storytelling and creating reports/newsletters more than standard presentations. The varied, customizable layouts and seamless integration with other Microsoft apps make it worth a look.

9. LibreOffice Impress 

Impress is a free, open source presentation tool with the basics covered for text documents, spreadsheets, presentations and more. It lacks some of the fancy features of paid options but gets the job done.

10. FlowVella

With its magazine-style format, FlowVella focuses on creating swipeable presentations for mobile devices. The conversational, storytelling format makes it easy to turn presentations into interactive experiences.

While PowerPoint still holds strong, these alternatives demonstrate the wide array of options now available for impactful and unique presentations. Taking the time to explore what each has to offer can open up new possibilities for how you present. So next time you need to make a presentation, don't default to PowerPoint without first considering if another tool may be a better fit.