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

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.

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Authors and Affiliations

  1. Duke University School of Medicine, Durham, NC, USA
    Jennifer W. Kim BA
  2. Department of Medicine, Division of General Internal Medicine, Duke University Medical Center, Durham, NC, USA
    Hayden B. Bosworth PhD, Martha Adams MD & Eugene Z. Oddone MD, MHSC
  3. Center for Health Services Research in Primary Care, Durham Veterans Affairs Medical Center, Durham, NC, USA
    Hayden B. Bosworth PhD, Corrine I. Voils PhD, Maren Olsen PhD & Eugene Z. Oddone MD, MHSC
  4. Department of Biostatistics and Informatics, Duke University Medical Center, Durham, NC, USA
    Maren Olsen PhD & Tara Dudley MStat
  5. Department of Biostatistics, University of North Carolina, Chapel Hill, NC, USA
    Matthew Gribbin MS

Authors

  1. Jennifer W. Kim BA
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  2. Hayden B. Bosworth PhD
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  3. Corrine I. Voils PhD
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  4. Maren Olsen PhD
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  5. Tara Dudley MStat
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  6. Matthew Gribbin MS
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  7. Martha Adams MD
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  8. Eugene Z. Oddone MD, MHSC
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Corresponding author

Correspondence to Eugene Z. Oddone MD, MHSC.

Additional information

The authors have no conflicts of interest to report.

This study was supported by the Eugene A. Stead Medical Student Research Scholarship to the first author, and an NHLBI Grant R01 HL070713 to the second author.

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Kim, J.W., Bosworth, H.B., Voils, C.I. et al. Brief report: How well do clinic-based blood pressure measurements agree with the mercury standard?.J GEN INTERN MED 20, 647–649 (2005). https://doi.org/10.1007/s11606-005-0112-6

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