Systematic Search for Health

Screening your search results

Screening is the process of determining which papers are included in your review. Learn more about those next processes in the Systematic and systematic-like review toolkit which covers the whole review.

There are two screening stages, ‘Title and Abstract Screening’ and ‘Full Text Screening’. Each screening stage is typically undertaken by two independent reviewers to minimise bias.

Screening process

Step 1: Refer to your inclusion and exclusion criteria

These criteria are developed when writing your protocol and should be established at that time as not to introduce bias. Find out about review protocols and inclusion/exclusion criteria in the Systematic and systematic-like review toolkit.

Inclusion criteria: Characteristics the study must have to be eligible to be included in the review.

Exclusion criteria: Characteristics that would exclude a study from inclusion in the review.

If you are using a tool e.g. Covidence to screen, set these criteria before importing your results into the screening tool

Step 2: Title and abstract screening

Reviewers will independently screen all articles by title and abstract to remove obviously irrelevant material. At this stage you may not need to provide justification for your exclusions:

1. Screen the titles and abstracts of your results against your inclusion and exclusion criteria.
2. Articles that do not meet the inclusion criteria do not move to the next screening stage.
3. Articles that meet inclusion criteria or those with unclear eligibility proceed to the second stage of screening, which involves a full-text review.
   • Often a third reviewer is used to resolve conflicts between other reviewers. This is often the person who is the foremost expert in the subject.

Step 3: Full text screening

Articles which were not excluded in the title and abstract screening stage undergo a full text review. Reviewers examine each article in detail to assess eligibility for inclusion in final review. 

1. Source the full text of all articles.
2. Review the full text and record reasoning for inclusion or exclusion.
   • If reviewers' inclusion and exclusion decisions conflict, use a third reviewer to resolve the decision. 

NOTE: When you are ready to source the full text (PDF) of records which make it to the full text screening stage in Covidence, you can export a list of these articles into a new EndNote Library. Then use a combination of EndNote’s “Find Full Text” feature and manual searching to source and attach the full text to these EndNote records. You can the upload these PDFs in bulk and Covidence will recognise and attach the documents to their corresponding record. See the Covidence guide for instructions.

PRISMA flow diagram

The PRISMA flow diagram is a tool which visually demonstrates your decisions through the screening process. The flow diagram is designed to make the selection process more transparent, clearly reporting the number of records in the search results, each screening stage, and data extraction. 

You can download your own copy of the PRISMA Flow diagram from the PRISMA statement website. We have developed a completed Example of the PRISMA Flow diagram so that you can see how it might be filled in.

Full documentation available in PRISMA 2020 Explanation and Elaboration paper, and PRISMA statement website.

*Consider, if feasible to do so, reporting the number of records identified from each database or register searched (rather than the total number across all databases/registers).
**If automation tools were used, indicate how many records were excluded by a human and how many were excluded by automation tools.

Covidence - a screening tool

Various applications are available to assist your team with the screening process. Deakin University provides all staff and students with access to screening tool Covidence. You can learn how to sign up as a Deakin University user and learn more about the tool on our Covidence page.

Continuing your review

From this point you will continue going through the steps to appraise the studies, extract the data, write the analysis and publish the study. For support for these steps, refer to the Systematic and systematic-like review toolkit or speak to your research team, colleagues and supervisors.