Article Text

Performance of popular pulse oximeters compared with simultaneous arterial oxygen saturation or clinical-grade pulse oximetry: a cross-sectional validation study in intensive care patients
  1. Ralf E Harskamp1,
  2. Luuk Bekker2,
  3. Jelle C L Himmelreich1,
  4. Lukas De Clercq1,
  5. Evert P M Karregat1,
  6. Mengalvio E Sleeswijk2 and
  7. Wim A M Lucassen1
  1. 1Department of General Practice, Amsterdam UMC Locatie AMC, Amsterdam, North Holland, The Netherlands
  2. 2Flevoziekenhuis, Almere, Flevoland, The Netherlands
  1. Correspondence to Ralf E Harskamp; r.e.harskamp{at}


Objectives To evaluate the performance of direct-to-consumer pulse oximeters under clinical conditions, with arterial blood gas measurement (SaO2) as reference standard.

Design Cross-sectional, validation study.

Setting Intensive care.

Participants Adult patients requiring SaO2-monitoring.

Interventions The studied oximeters are top-selling in Europe/USA (AFAC FS10D, AGPTEK FS10C, ANAPULSE ANP 100, Cocobear, Contec CMS50D1, HYLOGY MD-H37, Mommed YM101, PRCMISEMED F4PRO, PULOX PO-200 and Zacurate Pro Series 500 DL). Directly after collection of a SaO2 blood sample, we obtained pulse oximeter readings (SpO2). SpO2-readings were performed in rotating order, blinded for SaO2 and completed <10 min after blood sample collection.

Outcome measures Bias (SpO2–SaO2) mean, root mean square difference (ARMS), mean absolute error (MAE) and accuracy in identifying hypoxaemia (SaO2 ≤90%). As a clinical index test, we included a hospital-grade SpO2-monitor (Philips).

Results In 35 consecutive patients, we obtained 2258 SpO2-readings and 234 SaO2-samples. Mean bias ranged from −0.6 to −4.8. None of the pulse oximeters met ARMS ≤3%, the requirement set by International Organisation for Standardisation (ISO)-standards and required for Food and Drug Administration (FDA) 501(k)-clearance. The MAE ranged from 2.3 to 5.1, and five out of ten pulse oximeters met the requirement of ≤3%. For hypoxaemia, negative predictive values were 98%–99%. Positive predictive values ranged from 11% to 30%. Highest accuracy (95% CI) was found for Contec CMS50D1; 91% (86–94) and Zacurate Pro Series 500 DL; 90% (85–94). The hospital-grade SpO2-monitor had an ARMS of 3.0% and MAE of 1.9, and an accuracy of 95% (91%–97%).

Conclusion Top-selling, direct-to-consumer pulse oximeters can accurately rule out hypoxaemia, but do not meet ISO-standards required for FDA-clearance

  • COVID-19
  • respiratory measurement

Data availability statement

Data are available upon reasonable request. All data relevant to the study are included in the article or uploaded as supplementary information.

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See:

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Data availability statement

Data are available upon reasonable request. All data relevant to the study are included in the article or uploaded as supplementary information.

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  • REH and LB are joint first authors.

  • Contributors RH and LB designed the study protocol. LB was involved in the recruitment of patients for participation in data collection, supervised by MES. LB performed the statistical analysis and interpreted all data with statistical guidance from JCLH, LDC, EPMK, WL and RH. RH and LB drafted the manuscript and all authors contributed to its revision. All authors read and approved the final manuscript.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.