Use this checklist to determine if a source is appropriate:
Authority: Who wrote it? What credentials does s/he have? [PhD, affiliation with university]
Source: Where was it published? How was it selected for publication? [look at submission guidelines for evidence of peer review or other editorial processes]
Currency: When was it published? Has it appeared in other forms with/out revision?
Research: Are other sources cited in a bibliography/reference list? Are foot/endnotes used?
Bias: Is there an objective viewpoint? Is the author making assertions without documentation, or with questionable documentation? [e.g., her/his own work, crackpots]
Qualitative articles on medical topics can be somewhat trickier to find than quantitative, so rather than recreate the wheel here are some great tips.
In CINAHL use the CINAHL heading "Qualitative Studies" complemented by more detailed terms, including "Phenomenological Research" and "Focus Group," etc. You can also use these terms for keyword or natural language searches.
On the lower half of initial search box of CINAHL, try selecting Qualitative- Best Balance as a Clinical Query search limit.
For MEDLINE/Pubmed
Subject terms: MeSH
PubMed uses "Qualitative Research" or "Nursing Methodology Research" as a SUBJECT term.
The narrow qualitative query looks for the words qualitative and themes in titles and abstracts of articles. A modification of this strategy is linked below. It includes the MeSH term Qualitative Research, which was added to the MeSH vocabulary in 2003. You can copy and paste this search string into the Pubmed search box along with your other keywords for your search connecting it with AND.
qualitative research [MeSH] OR qualitative[tiab] OR themes[tiab]