4-. I just want to add the levels of evidence from strongest to weakest
· Systemic review of experimental studies (well-designed randomized controlled trials [RCTs])
· Meta-analyses of experimental (RCT) & quasi-experimental studies
· Integrative reviews of experimental (RTC) & quasi-experimental studies
· Single experimental study (RCT)
· Single quasi-experimental study
· Meta-analysis of correlational studies
· Integrative reviews of correlational & descriptive studies
· Qualitative research meta-synthesis & meta-summaries
· Single correlational study
· Single qualitative or descriptive study
· Opinions of respected authorities based upon clinical evidence, reports of expert committees (Grove, Gray, & Burns, 2015, p. 24)
Grove, S. K., Gray, J., & Burns, N. (2015). Understanding nursing research: Building an evidence-based practice(6th ed.). Retrieved from https://bookshelf.vitalsource.com/ #/books/9781455770601/cfi/20!/4/2/18/18/8/2/4/4/8@0:0
5-Let me put my share for peer-review as you mentioned this in your post. Feedback from colleagues with similar backgrounds, expertise and knowledge can be a valuable asset. Positive peer reviews contribute to increased funding opportunities, academic advancement and a good reputation. On the other hand, peer reviewers can fall prey to bias, both positive and negative, which can affect the prospects of the research being reviewed, independent of its quality (APA, 2018).
Peer reviewers are expected to meet strict deadlines, which is a challenge when one has numerous responsibilities. Reviewers are also expected to remain impartial during the review, which can be difficult if the research being reviewed is, for example, submitted by a rival researcher. During the review process, the reviewer must knowledgeably assess the quality of the research, honestly judge the importance of the research and must preserve confidentiality. It is essential that researchers are aware of the expectations and commitments required of a peer reviewer prior to becoming one. Although participating in peer review is a way to provide professional service, those who cannot meet the requirements should seriously consider whether being a peer reviewer is right for them.
American Psychological Association (2018). Peer review. Retrieved from
6-You mention Meta-analysis in your post, I have some more information about meta-analysis. Meta-analyses are a subset of systematic review. A systematic review attempts to collate empirical evidence that fits prespecified eligibility criteria to answer a specific research question (NCBI,2018). The key characteristics of a systematic review are a clearly stated set of objectives with predefined eligibility criteria for studies; an explicit, reproducible methodology; a systematic search that attempts to identify all studies that meet the eligibility criteria; an assessment of the validity of the findings of the included studies (e.g., through the assessment of risk of bias); and a systematic presentation and synthesis of the attributes and findings from the studies used. Systematic methods are used to minimize bias, thus providing more reliable findings from which conclusions can be drawn and decisions made than traditional review methods. Systematic reviews need not contain a meta-analysis. there are times when it is not appropriate or possible; however, many systematic reviews contain meta-analyses.
National Center for Biotechnology Information (2018). Meta-analysis in medical research. Retrieved from