Abstract Objective: Blood pressure measurement (BPM) is one of the most often performed procedures in clinical practice but especially office BPM is prone to errors. Automated office BPM (AOBPM) is highly standardised and compares well to ambulatory BPM but is time and space consuming since the patient is placed alone during the procedure. With this analysis we compared the accuracy of different calculation methods to evaluate if an abbreviation of the AOBP protocol is possible. Design and method: In our retrospective single centre study, we used all AOBPM (AOBPM protocol of the SPRINT study), collected over 14 months. Three sequential BPM (after 5 minutes of rest, spaced 2 minutes) were automatically recorded with the patient alone in a quiet room resulting in three systolic (S1S2S3) and diastolic (D1D2D3) values. We compared the result of the first BPM (S1/D1) and the mean of the first two BPM (S1S2/D1D2) with the mean of all three BPM (S1S2S3/D1D2D3) which was regarded as goldstandard for AOBPM. Results: We analysed 413 AOBP sets from 210 patients with a median age of 52 years (IQR 38–66). Median mmHg (IQR) for S1, S1S2 and S1S2S3 were 128.0 (117.0–142.0), 127.5 (117.0–140.0), 127.7 (116.8–139.2) and for D1, D1D2 and D1D2D3 80.0 (75.0–86.5), 80.0 (75.5–86.5), 80.3 (75.7–86.5), respectively. A Wilcoxon signed rank test determined that there was a statistically significant median increase of systolic blood pressure (BP) applying S1 compared to S1S2S3 (0.3mmHg, z = 2.315, p = 0.021) but not for S1S2 vs S1S2S3. For diastolic BP there was a no statistically significant difference for D1 vs. D1D2D3 but for D1D2 vs. D1D2D3 (0.2mmHg, z = 2.05, p = 0.040). Regarding agreement absolute difference was within 2 mmHg in 85.5% of the AOBPM comparing S1S2 vs. S1S1S3 and 93.2% for D1D2 vs D1D2D3, respectively (for all comparisons see table). Bland-Altman plots for all comparisons are shown in the figure. Conclusions: Based on our results differences between S1S2 vs S1S2S3 and D1D2 vs D1D2D3 are minimal and within acceptable limits of agreement. Therefore the automated procedure may be shorted to 2 measurements.
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