Open AccessManual or Automated Sphygmomanometer? A Historical Cohort to Quantify Measurement Bias in Blood Pressure Recording
Author(s) -
Nargesi Arash A.,
Ghazizadeh Zaniar,
Larry Mehrdad,
Morteza Afsaneh,
Heidari Firuzeh,
Asgarani Firuzeh,
Esteghamati Alireza,
Mohammad Kazem,
Nakhjavani Manouchehr
Publication year - 2014
Publication title -
the journal of clinical hypertension
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.909
H-Index - 67
eISSN - 1751-7176
pISSN - 1524-6175
DOI - 10.1111/jch.12400
Subject(s) - sphygmomanometer , medicine , confidence interval , blood pressure , cardiology , diastole , limits of agreement , nuclear medicine
The authors aimed to quantify end‐digit and threshold biases in blood pressure ( BP ) measurement with manual and digital sphygmomanometers. In a 3‐year follow‐up, end‐digit and threshold biases were investigated and a new index, called the deviation index, was used to quantify measurement bias. The distribution of systolic and diastolic BP s became close to normal after implementation of digital sphygmomanometers. The appearance of zero end digits decreased from 97% to 30% ( P <.0001). The deviation index decreased from 97% to 20% ( P <.0001). Mean systolic and diastolic BP s increased immediately after implementation of automated sphygmomanometers (124.22±0.83 vs 132.90±0.78 and 74.38±0.50 vs 80.43±0.51, respectively; P <.0001 for both) but showed a linear decreasing trend during follow‐up (systolic −3.59 mm Hg per year; 95% confidence interval, −5.57 to −1.61 [ P <.0001]; diastolic: −2.52 mm Hg per year; 95% confidence interval, −3.78 to −1.26 [ P <.0001]). Threshold bias decreased from 12.94% to 6.68% ( P <.0001). Replacing manual sphygmomanometers with digital devices decreased end‐digit and threshold biases in BP measurement. The deviation index can be used to quantify the magnitude of measurement bias.