Qualitative: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5813303/pdf/14.pdf Understanding the Meaning of Food in People With Type 2 Diabetes Living in Northern Appalachia

Quantitative: https://pubmed.ncbi.nlm.nih.gov/21986350/ Comparative effectiveness of patient education methods for type 2 diabetes: a randomized controlled trial

review both the methods and the limitations stated by the authors to identify where there may be plausible threats to internal validity. The test of plausibility is more than just being possible. There needs to be some real expectation of likelihood. For quantitative research, the possible threats to study reliability include:

• subject fatigue,
• subject motivation,
• subject learning,
• subject ability,
• tester skill,
• different testers, and
• test environment.

For qualitative research, the possible threats to study validity include:

• rival explanations
• negative cases
• triangulation
• design checks
• participant reactions to analysis
• intellectual rigor

See examples below:

Threats to Reliability; : Subject Fatigue: Not applicable, because participants were not tested. Subject Motivation: Not applicable, because participants were not required to do anything. . Subject Learning: Not applicable, because participants were not required to learn anything, or do anything. -- Subject Ability: Not applicable, because participants were not required to do anything. . Tester Skill: The researchers did not administer any tests to the participants, so tester (administrator) skill would not be a threat to this study. - Different Testers: The researchers did not administer any tests to the participants, so any differences between testers {administrators} would not be a threat to this study. - Test Environment: Not applicable, because participants were not being tested. Threats to Validity: Rival Explanations: There was no discussion of rival explanations, so this is a plausible threat to the validity of this study. . Negative Cases: There were only 8 cases in the sample and the authors did use specic quotes to illustrate the various responses received within the themes. The themes were very broad, leaving room for a very wide range of responses within the theme, including what might be considered to be a negative case. For example, for the theme regarding the things women did to relieve the PPD symptoms, alcohol abuse was included, which would certainly be the negative of a healthy coping response. Consequently, the themes allowed room for negative cases. which make this particular threat not likely to be plausible. - Triangulation: There were no alternative data collection methods used to validate the selfreports of the participants. Consequently, this is a plausible threat to the validity of this study. . Design Checks: There are denitely other design checks that should be accomplished, but there is no evidence that they were implemented. Furthermore, there is no discussion of aws in the data collection techniques. On the other hand, the authors were clear to point out that this research is only representative of the persons interviewed and should not be interpreted as representative of the larger population. Nevertheless. good research techniques should always be used and aws discussed, neither of which were done here, so this can certainly be considered a plausible threat to validity. -. Participant Reactions to Analysis: There is no evidence that the researchers shared their analysis with the participants. so this is a plausible threat to validity. One of the hallmarks of CBPR is the involvement of the priority community in all aspects of the research. The researchers described said that this research was CBPR, but by the way the methods and analysis are described, there is no evidence that the priority community was involved in anything other than as gate- keepers in facilitating getting the interviews. - Intellectual Rigor: The only thing that the researchers reported in terms of rigor was the reex journaling prior to and during data collection. This is one of the tools in the qualitative research toolbox for rigor, by itself, it is not sufcient to say that appropriate intellectual rigor was used for this study. Consequently, the lack of intellectual rigor. based upon this article, is lacking and is a plausible threat to the validity of this study