Appendix 1.

AMSTAR checklist for critical appraisal of systematic reviews.²⁸ Boxes are checked for the one systematic review that was included in this scoping review.

1. Did the research questions and inclusion criteria for the review include the components of PICO?
For Yes:	Optional (recommended)
Population	Timeframe for follow up	Yes No
Intervention
Comparator group
Outcome
2. Did the report of the review contain an explicit statement that the review methods were established prior to the conduct of the review and did the report justify any significant deviations from the protocol?
For Partial Yes: The authors state that they had a written protocol or guide that included ALL the following:	For Yes: As for partial yes, plus the protocol should be registered and should also have specified:
review question(s)	a meta-analysis/synthesis plan, if appropriate, and	Yes Partial Yes No
a search strategy	a plan for investigating causes of heterogeneity
inclusion/exclusion criteria	a plan for investigating causes of heterogeneity
a risk of bias assessment
3. Did the review authors explain their selection of the study designs for inclusion in the review?
For Yes, the review should satisfy ONE of the following:
Explanation for including only RCTs		Yes No
OR Explanation for including only NRSI
OR Explanation for including both RCTs and NRSI
4. Did the review authors use a comprehensive literature search strategy?
For Partial Yes (all the following):	For Yes, should also have (all the following):
searched at least 2 databases (relevant to research question)	searched the reference lists / bibliographies of included studies	Yes Partial Yes No
provided key word and/or search strategy	searched trial/study registries
justified publication restrictions (eg language)	included/consulted content experts in the field
	where relevant, searched for grey literature
	conducted search within 24 months of completion of the review
5. Did the review authors perform study selection in duplicate?
For Yes, either ONE of the following:
at least two reviewers independently agreed on selection of eligible studies and achieved consensus on which studies to include		Yes No
OR two reviewers selected a sample of eligible studies and achieved good agreement (at least 80%), with the remainder selected by one reviewer.
6. Did the review authors perform data extraction in duplicate?
For Yes, either ONE of the following:
at least two reviewers achieved consensus on which data to extract from included studies		Yes No
OR two reviewers extracted data from a sample of eligible studies and achieved good agreement (at least 80%), with the remainder extracted by one reviewer.
7. Did the review authors provide a list of excluded studies and justify the exclusions?
For Partial Yes:	For Yes, must also have:
provided a list of all potentially relevant studies that were read in full-text form but excluded from the review	Justified the exclusion from the review of each potentially relevant study	Yes Partial Yes No
8. Did the review authors describe the included studies in adequate detail?
For Partial Yes (ALL the following):	For Yes, should also have ALL the following:
described populations	described population in detail	Yes Partial Yes No
described interventions	described intervention in detail (including doses where relevant)
described comparators	described comparator in detail (including doses where relevant)
described outcomes	described study's setting
described research designs	timeframe for follow-up
9. Did the review authors use a satisfactory technique for assessing the risk of bias (RoB) in individual studies that were included in the review?
RCTs
For Partial Yes, must have assessed RoB from	For Yes, must also have assessed RoB from:
unconcealed allocation, and	allocation sequence that was not truly random, and	Yes Partial Yes No Includes only NRSI
lack of blinding of patients and assessors when assessing outcomes (unnecessary for objective outcomes such as all-cause mortality)	selection of the reported result from among multiple measurements or analyses of a specified outcome
NRSI
For Partial Yes, must have assessed RoB:	For Yes, must also have assessed RoB:
from confounding, and	methods used to ascertain exposures and outcomes, and	Yes Partial Yes No Includes only RCTs
from selection bias	selection of the reported result from among multiple measurements or analyses of a specified outcome
10. Did the review authors report on the sources of funding for the studies included in the review?
For Yes
Must have reported on the sources of funding for individual studies included in the review. Note: Reporting that the reviewers looked for this information but it was not reported by study authors also qualifies		Yes No
11. If meta-analysis was performed did the review authors use appropriate methods for statistical combination of results?
RCTs
For Yes:
The authors justified combining the data in a meta-analysis		Yes No No meta-analysis conducted
AND they used an appropriate weighted technique to combine study results and adjusted for heterogeneity if present.
AND investigated the causes of any heterogeneity
For NRSI
For Yes:
The authors justified combining the data in a meta-analysis		Yes No No meta-analysis conducted
AND they used an appropriate weighted technique to combine study results, adjusting for heterogeneity if present
AND they statistically combined effect estimates from NRSI that were adjusted for confounding, rather than combining raw data, or justified combining raw data when adjusted effect estimates were not available
AND they reported separate summary estimates for RCTs and NRSI separately when both were included in the review
12. If meta-analysis was performed, did the review authors assess the potential impact of RoB in individual studies on the results of the meta-analysis or other evidence synthesis?
For Yes:
included only low risk of bias RCTs		Yes No No meta-analysis conducted
OR, if the pooled estimate was based on RCTs and/or NRSI at variable RoB, the authors performed analyses to investigate possible impact of RoB on summary estimates of effect.
13. Did the review authors account for RoB in individual studies when interpreting/ discussing the results of the review?
For Yes:
included only low risk of bias RCTs		Yes No
OR, if RCTs with moderate or high RoB, or NRSI were included the review provided a discussion of the likely impact of RoB on the results
14. Did the review authors provide a satisfactory explanation for, and discussion of, any heterogeneity observed in the results of the review?
For Yes:
There was no significant heterogeneity in the results		Yes No
OR if heterogeneity was present the authors performed an investigation of sources of any heterogeneity in the results and discussed the impact of this on the results of the review
15. If they performed quantitative synthesis did the review authors carry out an adequate investigation of publication bias (small study bias) and discuss its likely impact on the results of the review?
For Yes:
performed graphical or statistical tests for publication bias and discussed the likelihood and magnitude of impact of publication bias		Yes No No meta-analysis conducted
16. Did the review authors report any potential sources of conflict of interest, including any funding they received for conducting the review?
For Yes:
The authors reported no competing interests OR		Yes No
The authors described their funding sources and how they managed potential conflicts of interest