Table 3.
Types of evidence available in meta-research studies (n = 100) evaluating the PRISMA Statement or extensions
| Type of evidence available | Frequency of studies |
|---|---|
| SR adherence to the PRISMA Statement or extensions | |
| Data on SR adherence to the PRISMA Statement [38–94] | 57 |
| Data on SR adherence to a particular item of the PRISMA Statement (e.g. searching item, risk of bias assessment item) [95–99] | 5 |
| Data on SR abstract adherence to the PRISMA-Abstracts extension [74, 100, 101] | 3 |
| Data on network meta-analysis adherence to the PRISMA-Network Meta-Analysis extension [102] | 1 |
| Data on rapid review adherence to the PRISMA Statement [103] | 1 |
| Data on SR adherence to draft versions of the PRISMA-Child and PRISMA-Protocols Child extensions [104] | 1 |
| Data on SR adherence to reporting standards derived from the PRISMA Statement [8, 105, 106] | 3 |
| Data on SR abstract adherence to items derived from the PRISMA Statement [107, 108] | 2 |
| Data on individual participant data meta-analysis adherence to items derived from the PRISMA Statement [109] | 1 |
| Characteristics associated with SR adherence to the PRISMA Statement | |
| Association between journal endorsement of the PRISMA Statement and SR adherence to PRISMA [38, 39, 46, 71, 77, 81, 84, 94] | 8 |
| Association between factors other than journal endorsement (e.g. type of journal, word count, year of publication) and SR adherence to PRISMA [38, 43, 44, 46–51, 54, 57–62, 64, 66, 68, 70, 71, 73–75, 77, 78, 80, 82–86, 88–90, 92, 94] | 37 |
| Mention of the PRISMA Statement or extensions in journal instructions | |
| Frequency of journals referring to the PRISMA Statement or extensions in the instructions to authors [46, 71, 77, 81, 84, 110–122] | 18 |
| Frequency of journals referring to the PRISMA Statement or extensions in the instructions to peer reviewers [112, 123] | 2 |
| Other | |
| Frequency of SR authors who reported using the PRISMA Statement to guide reporting [8, 71, 114, 115, 124] | 5 |
| Frequency of editors who are aware of the PRISMA Statement [111] | 1 |
| Frequency of inappropriate citation of the PRISMA Statement by authors [125] | 1 |
| Association between adherence to the PRISMA Statement and citation of SRs [126] | 1 |
| Authors’ perceived barriers and facilitators to use of the PRISMA-Equity extension [127] | 1 |
| Authors’ views on what items are most important to report in SRs [128–130] | 3 |
| Systematic reviews of meta-research studies evaluating some component of the PRISMA Statement or extensions [35–37, 131] | 4 |