USM's Academic Integrity Policy is one reason, but not the only one.
We cite in order to:
If the CITE feature in CINAHL gives you a URL like this one
https://doi-org.wv-o-ursus-proxy01.ursus.maine.edu/10.1186/s13018-021-02256-1
Then your DOI should look like this
https://doi.org/10.1186/s13018-021-02256-1
Add it to the end of your APA reference. This sample APA reference should look like this
Espejo-Reina, A., Carrascal-Morillo, M. T., & Delgado-Martínez, A. D. (2021).
Comparison of two different ways to apply a circular plaster cast for distal radius fractures: Biomechanical study. Journal of Orthopaedic Surgery & Research, 16(1), 1–6. https://doi.org/10.1186/s13018-021-02256-1