Background: Despite advantages of ambulatory and home blood pressure monitoring, office blood pressure measurement remains the principal method for the diagnosis and management of hypertension. There still seems to be too little evidence to date showing variation in blood pressure during a medical visit and the current recommendations are mainly based on expert's opinions. The aim of this study was to evaluate the difference between the first two blood pressure measurements performed during a preventive examination and to verify whether the second measurement could influence clinical decisions in non-hypertensive patients. Material and methods:The study included 52 consecutive patients without history of hypertension or other cardiovascular diseases. Blood pressure and heart rate (HR) were measured twice, the first reading after 5 minutes rest and the second 1 minute later. Results: Significant differences were found between the first (fBPM) and second (sBPM) blood pressure measurements, both systolic blood pressure (SBP) 142.4 mm Hg [interquartile range (IQR): 130.8-152.0] vs. 138.1 mm Hg (IQR: 125.8-149.5), p < 0.001 and diastolic blood pressure (DBP) 85.8 mm Hg (IQR: 80.0-91.5) vs. 83.9 mm Hg (IQR: 77.0-90.3), p < 0.001, and heart rate (HR) 73.1/min (IQR: 64.8-80.0) vs. 71.8/min (IQR: 64.8-77.3), p < 0.001. In 63.5% of the participants, the difference between the measurements was over 5 mm Hg for SBP values and in 23.1% of the participants for DBP values. According to fBPM, 53.8% of the patients met the criteria for the diagnosis of hypertension and according to sBPM 48.1% (NS). Conclusion:We demonstrated substantial discrepancies between blood pressure values taken during the first and the second preventive medical check-up visit performed in the workplace. Preventive examination in the workspace is associated with similar number of false-positive results when hypertension status is evaluated as compared to regular office visits.