How accurate is your home blood pressure monitor? Or that automatic cuff you slide your arm into at the local pharmacy?A new study finds the results can vary widely when it comes to office versus out-of-office measurements.Researchers compared blood pressure readings for 40,000 adults who participated in 65 published investigations.They compared ‘research office readings’ taken under controlled conditions to numbers recorded using:· Routine office or clinic visits· Automated blood pressure devices· Home BP devices· And ambulatory monitors, which are worn for 24 hours. The results showed blood pressure values from out-of-office methods were lower than those recorded in office settings. And they sometimes failed to meet existing out-of-office guidelines or benchmarks.The differences were more pronounced in participants with hypertension.On the other hand, routine office blood pressure tended to read slightly higher than research office BP.The “white coat effect” which causes patient anxiety may be to blame for the overestimation, according to the researchers.The authors say these findings highlight the need for clearer and more consistent blood pressure targets, no matter how your blood pressure is measured.Source: Annals of Internal MedicineAuthor Affiliations: Tung University College of Medicine, Taipei Veterans General Hospital, MacKay Medical College, Taipei Medical University, National Taiwan UniversityAnnals..Sign up for our weekly HealthDay newsletter