I am interest in the care of diabetic patients. As diabetes is on the rise it is important that nurses have the knowledge and skills to care for those who live with diabetes and its treatments.  My clinical issue of interest specifically, it to address whether patients being treated with metformin are at risk for vitamin B12 deficiency.  Metformin is frequently prescribed to diabetic patients.  Vitamin B12 is important to the health of the nervous system and nerve cells (Mayo Foundation for Medical Education and Research, 2021). My PICO question will be developed around the idea of prescribing a vitamin B12 supplement to diabetic patients on metformin.
Using database resources to search key words such as, metformin, vitamin B12 deficiency, and diabetes, I was able to retrieve lots of information.  According to McGonigle & Mastrian (2018), for best patient care healthcare workers must be able to retrieve evidence-based information to achieve best practices. 
The first data base I used was CINAHL & Medline Combined search and the Boolean/phrase used was metformin and vitamin B12, this search resulted in 238 articles.  Next, I used the filters to limit results by limiting information to peer-reviewed, full-text resources published between 2017-2021.  This resulted in 92 resources. With filters still activated I also used the Boolean, diabetes and vitamin B12 and metformin, this further reduced findings to 64 results. 
The second database I used was PubMed.  I used the same Boolean words, diabetes and vitamin B12 and metformin which resulted in 313 articles.  One thing I really enjoyed about PubMed filters is that you can check mark the randomized control trial.  After, I filtered the PubMed database to the randomized control trial information, I had 5 results. 
Strategies one may use to increase the rigor and effectiveness of a database search is to search for evidence by level of evidence, for example, the best evidence design is a systematic review that includes a randomized control trial (McGonigle & Mastrian, 2018). An example of a lower-level evidence would be a descriptive study (i.e., a qualitative study).  Another strategy to increase effectiveness of a database search in MEDLINE database is to use the subject set box and select systematic reviews (Walden University, 2020).