ABSTRACT
The process of appraising each individual piece of evidence that will be included in a literature review should be systematic and rigorous. Using an appropriate critical appraisal tool can assist in ensuring that each piece of evidence is evaluated consistently, and that no important issues are omitted. Qualitative, quantitative and mixed methods research have many similarities, but also important differences, which must be taken into account when appraising studies. Non-research evidence should be appraised using criteria appropriate to the type of evidence in question. Probability (or random) sampling is often considered the best method of sampling in quantitative research, as it has the greatest likelihood of achieving generalizability. The conclusions and recommendations from a study should address the research question, hypothesis or aim. The credibility of the study also rests on whether the presented findings are a faithful representation of the participants' views.
