This 2022 report of ICU cases included 3,069 participants, in which 13% were POC. This study not only showed that pulse oximeter readings are inaccurate, but that the discrepancy resulted in markedly different decisions in care. (https://jamanetwork.com/journals/jamainternalmedicine/article-abstract/2794196
The New England Journal of Medicine administered studies in 2014-2015, as well as the first half of 2020. “Thus, in two large cohorts, Black patients had nearly three times the frequency of occult hypoxemia that was not detected by pulse oximetry as White patients.” https://www.nejm.org/doi/full/10.1056/NEJMc2029240
A study done at VA facilities from 2013-2019 gave a total of 30,039 reading pairs (pulse ox and arterial blood gas) to be evaluated, found similar discrepancies seen in other studies. The results shared are extremely detailed. They bring up some excellent points about moving forward, And the page also has a few lovely charts that make the data easier to read. https://www.bmj.com/content/378/bmj-2021-069775
This 2005 paper in the Anesthesiology Journal studied 21 subjects (52% with dark skin). They found that three common Pulse Oximeters overestimated arterial oxygen saturation during hypoxia in dark-skinned individuals, especially as saturation levels fell dangerously low. https://pubs.asahq.org/anesthesiology/article/102/4/715/7364/Effects-of-Skin-Pigmentation-on-Pulse-Oximeter
This 2018 study in the Journal of Healthcare Engineering found that certain sensor designs showed a large error in dark-skinned subjects, and that the error could be reduced with the proper selection of sensor type. https://www.hindawi.com/journals/jhe/2018/3521738/
Welch Allen published this brochure highlighting efficacy of 3 major brands from a study done in of 36 subjects. They explain several of the factors that can effect readings, and in my understanding it seems to mention that manufacturers tend to focus on solving only one of those factors. https://www.welchallyn.com/content/dam/welchallyn/documents/Distributors/Henry_Schein/MC12025_ImportanceofProfessionalPulseOximetry.pdf
Fair Pulse Ox 