Optometry and Vision Science Research Guide: Practice session with Covidence and Zotero: Preschool vision screening programs in Canada, a scoping review

Zotero is an open-access, easy-to-use reference management tool that helps you collect, organize, cite, and share your research sources.

For this practice review, you will be using Zotero to manage your references and records, find and upload full-text, and in the writing and composition of your manuscript.

Zotero allows you to save references from library catalogs, research databases, and the Web; upload and organize PDFs, images, audio and video files, snapshots of web pages, and more; write annotations and attach them to citations; and create bibliographies using most major citation styles.

Designating a unique group library in Zotero for each review project helps you keep your references organized, share materials efficiently with your team, and maintain clear sets for duplicates and items moved to trash. This approach ensures each review is self-contained, supports collaboration, and makes it easier to track sources and decisions throughout your project

• To set up a shared library in Zotero, first create a new group online via the Groups tab and choose “Create a New Group.” Name your group (e.g., practice_review_yourname) and set it to closed membership so members must be invited to join. Closed or private groups allow sharing of attached files.
• After confirming your group settings, open Zotero desktop and click the sync button. Your new group library will appear on the left under Group Libraries.

You can now minimize Zotero and return to Covidence for the next steps

Zotero support

• How to set up a Group Library in Zotero (tutorial and video)
• Plugins for Zotero. Zotero
• Zotero for mobile, and the barcode scanner. Zotero

Team Settings

On the Team Settings screen, you can view your team’s progress and set rules for screening and reviewing. Data extraction currently has no team settings.

The default is “Everyone can do everything,” meaning all members can review, screen, extract data, and resolve consensus. For large or multi-site reviews, you can assign different groups to specific tasks, like screening or extraction, which helps manage workflow as data extraction can take a long time.

Click “Manage rules” to decide which team members do each step of the review. The “All studies must be screened by” option lets you specify who screens each study, helpful to ensure experienced reviewers look at every study. The “Conflicts can be resolved by” option controls who can resolve disagreements; assigned members will have this permission, otherwise anyone on the team can do it.

Covidence support

How to oversee a review and setup who does what, video and article.

Eligibility criteria 

Covidence reworked this section for a major software update in July 2023. The PICO structure is now explicit and you can use it to organize your inclusion and exclusion criteria. However, if you aren't using a PICO structure or aren't sure where to enter a term, you can always use the Other Inclusion and Exclusion field. To learn more about PICO, visit the page for Asking and Answering Clinical Questions.

For this review, we are going to be using the PCC (Population, Concept, Context) framework as oppose to the PICO (Population, Intervention, Comparison, Outcome) framework, which is traditionally used for systematic reviews. Learn more about PCC from the JBI Manual for Evidence Synthesis. 

PCC is designed to structure broader, exploratory questions where explicit interventions and outcomes may not be defined. In contrast, PICO supports focused clinical questions by specifying interventions and outcomes to facilitate targeted evidence synthesis and analysis. PCC is better suited for research questions that seek to map the extent and nature of literature, particularly outside strictly clinical areas, whereas PICO is structured for assessing effectiveness or impacts of specific interventions in clinical context.

Highlights

Covidence allows you to input certain keywords that might indicate inclusion or exclusion for reviewers. Inclusion key words or phrases will be highlighted in green, and exclusion key words or phrases will be highlighted in red. This section is incredibly useful for larger teams as all of the key words and phrases can be customized for your review. 

Let's ADD+ some highlights for our practice review:

Full-text exclusion reasons

These exclusion criteria are going to be more specific as they will be used for the full-text review. Covidence pre-populates the list of exclusion reasons with popular options, such as wrong does, paediatric population, wrong setting, wrong study design, wrong intervention etc. If you like, you can add your own exclusion reasons as well as delete those that there by default. 

Inclusion reasons are not used in full-text review; you have already indicated in the Title and Abstract screening that you are including the article for further review of the full-text, so the full-text review is just going to be a matter of excluding the article from the final data extraction.

Always SAVE before leaving the settings page!

Covidence Support

Creating and managing eligibility criteria, article and video

Study Tags

In Covidence, Study Tags are an effective way to identify and organize important studies, such as references that provide excellent background for your introduction or discussion, even if they don’t meet inclusion criteria for your results. Custom tags help you quickly add notes, track the status of articles, or flag items for specific use by the review team.

Some tags, such as “Ongoing Study” and “Awaiting Classification,” are built into Covidence by default—these cannot be deleted, as they are automatically counted in your PRISMA chart for tracking review flow. Custom tags (e.g., “pending review,” “full-text on order,” “Background/context information,” or “Covidence support”) can be added and filtered to manage your references efficiently.

To create or manage tags, go to the ‘Study tags’ page in Covidence settings where you can add new tags or delete custom tags. Tags are visible to all reviewers and are included when exporting lists of references to Excel/CSV, making it easier to collaborate and track study status throughout your project.

Covidence support

How to create and manage study tags, article.

Review settings

The Review Settings screen lets you change your review’s name and type (like scoping, umbrella, or narrative review). You can update details such as your search strategy, which is helpful for team projects.

By default, Covidence requires two reviewers to screen each study to minimize bias. However, with Extraction 2.0, you can change this to just one reviewer, which can be useful for solo projects. Extraction 1.0 (mainly used for classic systematic reviews of interventional studies and Cochrane reviews) requires two reviewers.

It’s best practice to have at least two reviewers for structured reviews, including scoping and literature reviews. This is essential for minimizing bias and you should ideally be working on a review with a team.

For our practice review let's add our search strategy details:

• Date of Last Search
• Strategy: 

((((vision[Title/Abstract] OR eye[Title/Abstract]) AND (screen*[Title/Abstract] OR exam*[Title/Abstract])) AND (pre?school*[Title/Abstract] OR kindergarten[Title/Abstract] OR toddler*[Title/Abstract] OR p?ediatric[Title/Abstract])) AND (Canada[Title/Abstract] OR Alberta[Title/Abstract] OR Ontario[Title/Abstract] OR Quebec[Title/Abstract])) OR ((("Vision Screening"[Mesh]) AND "Child, Preschool"[Mesh]) AND "Canada"[Mesh])

• Now for the purposes of working through the references of our Practice Review, let's change all of the Reviewers Required to 1.
• Ensure that extraction 2 is selected and SAVE.

Covidence support

How to configure settings, article and video

Learn more about using Covidence for a Cochrane Review, article and video

Database: Pubmed (National Library of Medicine)

Search strategy (example):

((((vision[Title/Abstract] OR eye[Title/Abstract]) AND (screen*[Title/Abstract] OR exam*[Title/Abstract])) AND (pre?school*[Title/Abstract] OR kindergarten[Title/Abstract] OR toddler*[Title/Abstract] OR p?ediatric[Title/Abstract])) AND (Canada[Title/Abstract] OR Alberta[Title/Abstract] OR Ontario[Title/Abstract] OR Quebec[Title/Abstract])) OR ((("Vision Screening"[Mesh]) AND "Child, Preschool"[Mesh]) AND "Canada"[Mesh])

This search is as example of balancing indexing lanaguage (MeSH) with natural language. The scope for this term is deliberately narrow and this example is for practice only.

Database: Scopus (Elsevier)

Search strategy (example):

( TITLE-ABS-KEY ( vision OR eye W/2 ( screen* OR exam* OR test* ) ) AND TITLE-ABS-KEY ( pre?school* OR kindergarten OR toddler* OR p?ediatric ) AND TITLE-ABS-KEY ( canada OR ontario OR alberta OR quebec ) )

A "Maybe" vote is treated the same way as a "Yes" vote, meaning that it will move that citation forward in your review. 

If in dual reviewer mode, you can filter those citations that you have cast one "Maybe" vote on by using the filter function at the top of your 'Awaiting other reviewer' list. If in dual reviewer mode and a citation receives two "Yes"/"Maybe"votes it will move forward in your review and you'll be able to see those votes cast by clicking on "History" underneath each citation.

If the second vote is a "No" then that citation will move to your 'Resolve conflicts' list. Here you won't be able to see those "Maybe" votes unless they were cast by you, as seeing your co-reviewer's previous votes can lend itself to biasing the adjudicating vote. 

You won't be able to generate your list of citations that received a "Maybe" vote during title and abstract screening. All voting is blinded meaning that if you are in dual reviewer mode, your co-reviewer won't be able to see which citations you voted "maybe" on until they have cast their vote, and if this vote is also a "Yes" or a "Maybe".  

During the full-text review stage in Covidence, you can streamline access to articles and maintain thorough review documentation by integrating with Zotero. Here’s how the process works:

• Export studies missing full text from Covidence as an EndNote XML or RIS file. This can be done via the “Bulk upload PDFs” option in the full-text review section, ensuring that you have a precise list of which articles still require full-text retrieval.
• Import this file into Zotero using the desktop app. Once imported, use Zotero’s “Find Available PDFs” feature to automatically locate and attach as many full-text PDFs as possible. You can also manually attach files and use Zotero add-ons to check for retractions before proceeding.
• After attaching PDFs to the correct references, select all records with PDFs and export them from Zotero as an EndNote XML file, making sure to include both “Export Notes” and “Export Files” so that PDFs are packaged with the citation data.
• Back in Covidence, use the bulk upload tool to import the updated XML from Zotero. Covidence will automatically match PDFs to their corresponding records in the review and make the documents available to all team members for assessment.

This workflow lets you take advantage of Zotero’s full-text retrieval and reference management, ensures you are using the most accurate records, and provides a reliable way to track full-text acquisition and keep your review materials organized

The data extraction template is pre-populated with common data options for interventional, randomized controlled trials which is designed for a systematic review. However, we are going top publish a customised template to account for our scoping review protocol. Every data extraction template can be fully customised to meet the needs of your team. 

This is also where you can publish instructions for reviewers, so that everyone is on the same page. You must publish the template in order to utilize your extraction fields. 

Sample data extraction template, for set up in Covidence:

Covidence support

• How to create, publish and edit a data extraction template, video and article.
• How to export data to excel using extraction 2.0, video and article
• What does extraction 2.0 data look like when exported to Excel? video and article
• How to use multi-select checkboxes, article

The Quality Assessment template, and why we're not using this for our scoping review

Covidence’s quality assessment template is designed to capture risk of bias (ROB) directly within your review workflow. When you reach the quality assessment stage, Covidence offers a built-in template based on the Cochrane Risk of Bias (RoB) tool, which is widely recognized for evaluating randomized controlled trials. 

Risk of bias assessments are not typically performed in scoping reviews because the purpose of a scoping review is to provide an overview of the breadth of available evidence, without critically appraising or judging the quality or validity of individual studies. Scoping reviews aim to map the literature broadly, including studies regardless of methodological rigor or risk of bias.

In contrast, risk of bias assessment is a key component of systematic reviews, where the goal is to synthesize high-quality evidence and make clinical or policy recommendations. Systematic reviews must evaluate the internal validity of each included study to identify potential sources of bias that could affect the results and conclusions; this step is essential to ensure transparency and reliability in the final recommendations

Covidence support

How to start a quality assessment, video and articles

PRISMA chart

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flowchart is an evidence-based minimum set of items for reporting in systematic reviews and meta-analyses. PRISMA statements are often required with protocol manuscript submissions in the health sciences. Covidence will automatically generate a PRISMA statement for each review.

You can access your review’s PRISMA flowchart at any time from your Review Summary page. When you import references, they will immediately be displayed in your PRISMA flowchart. As you progress through your review, each stage of the PRISMA will continuously update to reflect your completed work. The PRISMA statement should be included in the Methods section of your manuscript.

Covidence support

• How to export and interpret PRISMA, video and article.

Zotero can be used to insert in-text citations directly into your document while you write. By using the Zotero plugin for Word, Google Docs, or LibreOffice, you can quickly add citations from your Zotero library in any major citation style. Zotero automatically builds your bibliography as you go, ensuring in-text citations and the reference list stay perfectly matched and formatted