Mixed Method, or Multimethod Research, utilizes more than one research method to increase the reliability of the data. Although rooted in quantitative research, more researchers are beginning to utilize both quantitative and qualitative research methods in Mixed Method research.
The following article from The Encyclopedia of Research Design provides a fuller description of Mixed Methods.
Mixed method research is found under either the subject heading Qualitative Research or Quantitative Research. The best method of discerning if an article uses mixed methods is to read the article. Sometimes the article title or sub-title may indicate a mixed method was used.