Journal of General Internal Medicine

, Volume 20, Issue 7, pp 647–649

Brief report: How well do clinic-based blood pressure measurements agree with the mercury standard?

Authors

  • Jennifer W. Kim
    • Duke University School of Medicine
  • Hayden B. Bosworth
    • Department of Medicine, Division of General Internal MedicineDuke University Medical Center
    • Center for Health Services Research in Primary Care, Durham Veterans Affairs Medical Center
  • Corrine I. Voils
    • Center for Health Services Research in Primary Care, Durham Veterans Affairs Medical Center
  • Maren Olsen
    • Center for Health Services Research in Primary Care, Durham Veterans Affairs Medical Center
    • Department of Biostatistics and InformaticsDuke University Medical Center
  • Tara Dudley
    • Department of Biostatistics and InformaticsDuke University Medical Center
  • Matthew Gribbin
    • Department of BiostatisticsUniversity of North Carolina
  • Martha Adams
    • Department of Medicine, Division of General Internal MedicineDuke University Medical Center
    • Department of Medicine, Division of General Internal MedicineDuke University Medical Center
    • Center for Health Services Research in Primary Care, Durham Veterans Affairs Medical Center
Original Article

DOI: 10.1007/s11606-005-0112-6

Cite this article as:
Kim, J.W., Bosworth, H.B., Voils, C.I. et al. J GEN INTERN MED (2005) 20: 647. doi:10.1007/s11606-005-0112-6

Abstract

BACKGROUND: Obtaining accurate blood pressure (BP) readings is a challenge faced by health professionals. Clinical trials implement strict protocols, whereas clinical practices and studies that assess quality of care utilize a less rigorous protocol for BP measurement.

OBJECTIVE: To examine agreement between real-time clinic-based assessment of BP and the standard mercury assessment of BP.

DESIGN: Prospective reliability study.

PATIENTS: One hundred patients with an International Classification of Diseases—9th edition code for hypertension were enrolled.

MEASURES: Two BP measurements were obtained with the Hawksley random-zero mercury sphygmomanometer and averaged. The clinic-based BP was extracted from the computerized medical records.

RESULTS: Agreement between the mercury and clinic-based systolic blood pressure (SBP) was good, intraclass correlation coefficient (ICC)=0.91 (95% confidence interval (CI): 0.83 to 0.94); the agreement for the mercury and clinic-based diastolic blood pressure (DBP) was satisfactory, ICC=0.77 (95% CI: 0.62 to 0.86). Overall, clinic-based readings overestimated the mercury readings, with a mean overestimation of 8.3 mmHg for SBP and 7.1 mmHg for DBP. Based on the clinic-based measure, 21% of patients were misdiagnosed with uncontrolled hypertension.

CONCLUSIONS: Health professionals should be aware of this potential difference when utilizing clinic-based BP values for making treatment decisions and/or assessing quality of care.

Key words

blood pressure measurement assessmentclinic methodmercury device

Copyright information

© Society of General Internal Medicine 2005