Discussion
We here present the first randomized study comparing 24 h ABPM with hourly measurements to 24 h ABPM using the currently recommended frequencies of 2–3 measurements per hour in a patient-population covering a broad range of BP levels. We found a good agreement between HF-ABPM and LF-ABPM for both SBP and DBP values. In addition, LF-ABPM was rated slightly less painful during cuff inflation. Our data support that one measurement every hour is sufficient to achieve correct values for BP as well as for BP variability.