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Covidence

New extraction and quality assessment in Covidence

NEW! Covidence has new data extraction and quality assessments.  New reviews will default to the Data Extraction 2.0 template.  Instructions for the original extraction and assessment forms are below the instructions for the 2.0 versions in each box.

To view or edit which extraction version is enabled for your review simply go to your review’s Settings page to select your preferred data extraction template. Be sure to save any changes you make.  Note: any data completed in extraction 1.0 or 2.0 cannot be migrated over.

 

Quality Assessment

Quality Assessment 2.0

Covidence now has customizable Quality Assessment forms, as well as the Cochrane Risk of Bias.

Access your Quality Assessment (QA) template

To access your template, select Quality assessment template. Publishing a quality assessment template is optional.

The default template

The default QA template is Cochrane’s Risk of Bias (RoB). If you want to use a different tool, select I want to start from scratch in the Editor to delete the RoB domains and start with an empty template. If you don’t want to do quality assessment in your review, don’t publish your QA template and QA will not appear for the extractors of your review. 

Note: You cannot use multiple tools per review, but you can include domains from multiple tools within your quality assessment form.

Add a domain 

To add a domain, select the Add (+) button above where you want to add the domain and choose one of the following options: 

  • New domain: This creates a blank domain with three blank judgements. 
  • Duplicate this domain: Use this if your domain has the same judgements, so you just need to change the label.

Add a new judgement 

Each domain starts with three judgements. You can add a judgement in the same way as you’d add a new line in Word. Move your insertion point to the end of one of your judgements and then press ENTER on your PC keyboard or RETURN on your Mac keyboard. 

Save and Publish 

You’ll need to press Save in the upper right corner to retain any changes you’ve made to your template. If your template isn’t published yet, press Publish and reviewers will be able to start extracting their first study. To start extraction, you must publish a data extraction template, however quality assessment is optional. 

Note: If you start extracting a study, you will not be able to change the form for that study. If you're unsure about whether you'll need to make changes, pilot your form outside of Covidence first. 

To find more information on this method of extracting data in Covidence, check out the Covidence Knowledge Base.

 

Quality Assessment (Original)

Once you have completed full text screening, included articles will be moved to the Extraction portion of the review, where you can extract data from each study and rate its quality.  To assess quality, Covidence has built in the Cochrane Risk of Bias (RoB) template.  You can choose to use the Cochrane tool (which is designed for rating RCTs and cannot be used for other study types), or you can customize the questions available for Risk of Bias to create your own template. 

You must choose either the Cochrane RoB or a custom RoB.  If you choose the custom RoB, you cannot change your selection back to Cochrane.

Categories of the Cochrane Risk of Bias tool

Regardless of whether you choose the Cochrane tool or another RoB tool, make sure you are using a validated critical appraisal tool. You can find a short list of critical appraisal tools in the box below, but there are other tools available. Just remember to use a tool that is appropriate for the study design or study designs that have been included in your review.

Quality Assessment Tools

Data Extraction

Extraction 2.0

Covidence has updated their extraction features!  You can use the editor to add fields to your extraction templates, or you can create your own from scratch.

Accessing your data extraction template

To access extraction, from the Review Summary screen, select the number of studies you have to extract. 

To access your template, select Data Extraction Template, located above the included study list. 

The data extraction template has three panels: the editor in the center, the preview on the right, and any item settings or notes to extractors on the left.

 

The Editor is in the center. You can fully edit the template in the Editor

The Preview is on your right. It’s a preview of what the extraction form will look like. When you change something in the Editor, the change will be reflected in the Preview. 

The Item settings are on your left. Select an item in the Editor to change its settings, such as instructions to extractors.

Add an item 

To add an item, select the Add (+) button above where you want to add the item and choose one of the following options: 

  • Text field. Use this to extract text and numbers. When extracting, the size of the text field will increase to accommodate the amount of text that’s being entered. 
  • Single choice item. Use this when you have a defined list of options and you want the extractor to choose one. 
  • Heading or Subheading. Use these to group and separate your items.

Instructions to extractors 

Text fields and single choice items allow you to communicate item specific instructions to your extractors. For example, for a single choice item, you might want to communicate to your extractors that they should only select an option if specific criteria are met. To add instructions, select the item, and then add the text in Item settings. The text will appear in the extraction form under the item’s label.

Save and Publish 

You’ll need to press Save in the upper right corner to retain any changes you’ve made to your template. If your template isn’t published yet, press Publish and reviewers will be able to start extracting their first study. To start extraction, you must publish a data extraction template, however quality assessment is optional. 

Note: If you start extracting a study, you will not be able to change the form for that study. If you're unsure about whether you'll need to make changes, pilot your form outside of Covidence first. 

To find more information on this method of extracting data in Covidence, check out the Covidence Knowledge Base

Data Extraction (original)

When you begin data extraction, you will see a screen like the one shown below. The center pane shows the general areas of data extraction and allows for quick navigation between each.

Note that the data extraction form has been designed to follow your PICO format. This format works best with interventional study designs, but it can be used with other study designs as well. 

The first study you begin data extraction for in each review will become your "Review Template." The tables set up here will be carried over to subsequently started extractions, where they can be individually edited if needed. Only the first reviewer can edit the template; the first reviewer can be changed at any time by clicking "Manage reviewers" on the study's pane Extraction page.

Data extraction template including categories for Summary, Identification, Methods, Population, Interventions, Outcomes.

To find more information on extracting data in Covidence, check out the Covidence Knowledge Base

For general data extraction principles and instructions, check out the resources in the Data Extraction Guides box.

Consensus

Once you’ve published your data extraction template, a Begin extraction button will appear for each study. Select Begin extraction to start extracting. The study's PDF should appear on the left. PDFs need to be uploaded during full text review. On the right side is the data extraction or quality assessment form. Use the tabs to switch between them. You can change the relative width of the PDF panel and the extraction panel by clicking ad dragging the divider. 

Each text field and single choice item has a comment. Select the comment icon to enter a comment. This will be visible during consensus, but not to the other reviewer. 

To access the QA tool for a study, select the Quality Assessment tab. Quality assessment is optional. If there's no Quality Assessment tab, then the quality assessment template hasn't been published. 

Save and Send for Consensus 

Select Save periodically and when you leave the extraction screen. Once you’ve finished data extraction and quality assessment for that study, press Send for Consensus. At the moment, once you’ve sent the form to consensus, this can’t be undone

Consensus

Once two reviewers have extracted data, you will need to compare their data and come to consensus. It is consensus data which will be exported later on. You can access comparison and consensus from the summary section in the Data Extraction navigation pane.

If a reviewer has not collected certain data points, the cell will be outlined in red. Missing data will be greyed out.

Study identification table with columns for consensus decision and each reviewer, and rows for each domain such as sponsorship source, country, setting, comment, author's name, institution, email, address, and more.,

Assigning reviewers

A review is automatically assigned to the reviewer that selects Save or Send to consensus first within the study.