These findings are not meant to imply that all or even most automated machines were inaccurate but that using automated machines as a general method of assessing blood pressure is inaccurate. Unfortunately, it is impossible for physicians or patients to know which of the many automated blood pressure machines available in their community are accurate or reliable.
Conclusions
We found that automated blood pressure machines from a representative community-based sample did not meet accepted standards of accuracy and reliability of measurement. Accuracy of readings was especially uncertain for patients having larger- or smaller-than-average arm sizes. Even patients with a medium-sized arm can expect significant and unacceptable variability in blood pressure readings, even with the same machine. We agree with the recommendations of the American College of Physicians, which caution against managing patients solely using blood pressure readings obtained with self-monitoring blood pressure devices.10 Although further study in this area may be useful to strengthen this recommendation, we recommend that patients not rely on the results of in-store automated blood pressure devices. The manufacturers of these devices should also monitor the accuracy and reliability of these devices frequently and make maintenance information easily available.
Acknowledgments
Dr Roetzheim was supported through a Generalist Physician Faculty Scholars Award from the Robert Wood Johnson Foundation. Marney Goldstein is a student at the University of South Florida College of Medicine and was supported by a summer research assistantship sponsored by the Florida Academy of Family Physicians and the American Academy of Family Physicians. We also wish to thank Christopher Roever for his assistance in the collection of the data.