The PRISMA 2020 Statement differentiates between records, reports and studies. It is important to understand the difference and to use the correct terminology consistently throughout a systematic review.
In the PRISMA 2020 Statement (Page, 2021) these terms are defined as:
Record—The title or abstract (or both) of a report indexed in a database or website (such as a title or abstract for an article indexed in Medline). Records that refer to the same report (such as the same journal article) are “duplicates”; however, records that refer to reports that are merely similar (such as a similar abstract submitted to two different conferences) should be considered unique.
Report—A document (paper or electronic) supplying information about a particular study. It could be a journal article, preprint, conference abstract, study register entry, clinical study report, dissertation, unpublished manuscript, government report, or any other document providing relevant information
Study—An investigation, such as a clinical trial, that includes a defined group of participants and one or more interventions and outcomes. A “study” might have multiple reports. For example, reports could include the protocol, statistical analysis plan, baseline characteristics, results for the primary outcome, results for harms, results for secondary outcomes, and results for additional mediator and moderator analyses
Records, reports and studies are highlighted in the sample PRISMA 2020 flow diagram below. Authors often don't realise that these are different things.
A record is a bibliographic DESCRIPTION of a report, which you might find through searching databases, registers or other sources. You could think of it as a catalogue entry, or a citation.
PRISMA 2020 defines it as:
Record—The title or abstract (or both) of a report indexed in a database or website (such as a title or abstract for an article indexed in Medline). Records that refer to the same report (such as the same journal article) are “duplicates”; however, records that refer to reports that are merely similar (such as a similar abstract submitted to two different conferences) should be considered unique. (Page, 2021)
In Ovid Medline a record looks like this:
Duplicate records are routinely removed before screening begins.
When you search multiple databases you will often find a number of records that describe the same report. Although they may have slight variations in layout, it will be clear that they refer to the same:
These are examples of duplicate records in Endnote:
These are examples of duplicate records in Covidence:
The following records in EndNote are NOT duplicates, as the journals are different.
A report is the FULL TEXT document.
PRISMA 2020 defines it as:
Report—A document (paper or electronic) supplying information about a particular study. It could be a journal article, preprint, conference abstract, study register entry, clinical study report, dissertation, unpublished manuscript, government report, or any other document providing relevant information (Page, 2021)
This is the front page of a report. In this case it is a full text journal article. 
PRISMA 2020 defines a study as:
Study—An investigation, such as a clinical trial, that includes a defined group of participants and one or more interventions and outcomes. A “study” might have multiple reports. For example, reports could include the protocol, statistical analysis plan, baseline characteristics, results for the primary outcome, results for harms, results for secondary outcomes, and results for additional mediator and moderator analyses (Page, 2021)
Studies can be qualitative, or quantitative, or both, but it can be easiest to understand in the context of an RCT. A group of researchers often produce many reports describing one study, and these need to be reviewed together as part of a systematic review.
If you are screening reports in Covidence, it provides an option to merge multiple reports into the one study, and this will be reflected in the PRISMA flow chart.
Page M J, Moher D, Bossuyt P M, Boutron I, Hoffmann T C, Mulrow C D et al. PRISMA 2020 explanation and elaboration: updated guidance and exemplars for reporting systematic reviews BMJ 2021; 372 :n160 doi:10.1136/bmj.n160