Diagnosis and Assessment
Subgroup Members: Mark Gelfer, MD; Lyne Cloutier, RN, PhD; Sheldon Tobe, MD, MSc (HPTE); Maxime Lamarre-Cliche, MD; Peter Bolli, MD; Guy Tremblay, MD; Donna McLean, RN, NP, PhD; Donald W. McKay, PhD; Raj Padwal, MD, MSc
Central Review Committee: Doreen M. Rabi, MD, MSc; Stella S. Daskalopoulou, MD, PhD; Kelly B. Zarnke, MD, MSc; Kaberi Dasgupta, MD, MSc; Kara Nerenberg, MD, MSc
Chair: Doreen M. Rabi, MD, MSc
Editor: Raj Padwal, MD, MSc
This information is based on the CHEP guidelines published in Daskalopoulou SS, Rabi DM, Zarnke K, for the Canadian Hypertension Education Program. The 2015 Canadian Hypertension Education Program recommendations for blood pressure measurement, diagnosis, assessment of risk, prevention, and treatment of hypertension. Can J Cardiol 2015;31:549-568.
- Health care professionals who have been specifically trained to measure BP accurately should assess BP in all adult patients at all appropriate visits to determine cardiovascular risk and monitor antihypertensive treatment (Grade D).
- Use of standardized measurement techniques and validated equipment for all methods (office blood pressure measurement (OBPM), automated office blood pressure (AOBP), home blood pressure measurement (HBPM) and ambulatory blood pressure measurement (ABPM) is recommended (Grade D; see Supplemental Table S2, Section VII. Home BP Monitoring, Section VIII. Ambulatory BP Monitoring and Table 1).
- Four approaches can be used to assess BP (see text for definitions):
- i. Office BP measurement (OBPM): Measurement using electronic (oscillometric) upper arm devices is preferred over auscultation (Grade C) (unless specified otherwise, henceforth OBPM refers to electronic (oscillometric) measurement). When using mean OBPM, an SBP ≥140 mm Hg or a DBP ≥90 mm Hg is high, and an SBP between 130-139 mm Hg and/or a DBP between 85 and 89 mm Hg is high-normal (Grade C).
- Automated Office Blood Pressure Measurement (AOBP): When using AOBP (see Supplemental Table S2, AOBP), a displayed mean SBP ≥135 mm Hg or DBP ≥85 mm Hg is high (Grade D).
- Ambulatory BP Measurement (ABPM): Using ABPM (see Recommendations in Section VIII, ABPM), patients can be diagnosed as hypertensive if the mean awake SBP is ≥135 mm Hg or the DBP is ≥85 mm Hg or if the mean 24-hour SBP is ≥130 mm Hg or the DBP is ≥80 mm Hg (Grade C).
- Home BP monitoring (HBPM): (see Recommendations in Section VII, HBPM) Patients can be diagnosed as hypertensive if the mean SBP is ≥135 mm Hg or the DBP is ≥85 mm Hg (Grade C). If the OBPM is high and the mean home BP is <135/85 mm Hg, it is advisable to either repeat home monitoring to confirm the home BP is <135/85 mm Hg or perform 24-hour ABPM to confirm that the mean 24-hour ABPM is <130/80 mm Hg and the mean awake ABPM is <135/85 mm Hg before diagnosing white coat hypertension (Grade D).
1. Health care professionals who have been specifically trained to measure BP accurately should assess BP in all adult patients at all appropriate visits to determine cardiovascular risk and monitor antihypertensive treatment (Grade D).
Direct evidence supporting the merits of BP screening is scarce; thus, this recommendation is largely based upon expert consensus and specifically, the reality that if BP screening is not performed, hypertension cases will remain undetected.
Blood pressure screening frequency and timing may vary between patients and is left to the discretion of each practitioner. Periodic health exams, visits for assessment of other cardiovascular risk factors, urgent office visits for neurological or cardiovascular related issues, medication renewal visits are examples of medical visits considered appropriate for blood pressure measurement (1). Hypertension-related complications are more common in older patients, in those with multiple cardiovascular risk factors, and in patients with pre-existing cardiovascular disease; furthermore, treatment-related absolute risk reductions are greater in high-risk subgroups (2-4). Accordingly, the frequency of screening may increase depending on the clinical situation.
Accurate assessment of blood pressure is necessary for proper diagnosis, precise cardiovascular risk assessment, to gauge the necessity for intervention, and to monitor treatment effect. Accurate blood pressure measurement requires standardized measurement techniques, calibrated equipment and valid interpretation of readings (1,5-8) The importance of accurate measurement cannot be overstated – it is important to avoid both false positive and false negative results. A recent Canadian cluster randomized controlled trial demonstrated that a comprehensive cardiovascular risk assessment and education program implemented in community pharmacies reduced cardiovascular mortality compared to no intervention (9). BP assessment was an important component of the risk assessment performed in this trial.
2. Use of standardized measurement techniques and validated equipment for all methods (office blood pressure measurement (OBPM), automated office blood pressure (AOBP), home blood pressure measurement (HBPM) and ambulatory blood pressure measurement (ABPM) is recommended (Grade D; see Supplemental Table S2, Section VII. Home BP Monitoring, Section VIII. Ambulatory BP Monitoring and Table 1).
Studies have repeatedly demonstrated that blood pressure is not carefully assessed in clinical practice, especially when measured manually using an auscultatory technique (10-15) Summaries of standardized techniques for ambulatory blood pressure measurement (ABPM; Table 1), home blood pressure measurement (HBPM; Section VII), automated office (AOBP; Table S2) and manual office (MOBP; Table S2) have been provided.
Deviations from standardized blood pressure measurement techniques can introduce inaccuracy and lead to misclassification of cardiovascular risk (5-7,11,12,14-20). For example, measuring blood pressure with the arm positioned below the level of the heart can lead to blood pressure overestimation of 7-10/8-11 mm Hg, compared with positioning the arm correctly at the level of the atria (21-25). Leg crossing during blood pressure measurements may increase values by 8-10/4-5 mm Hg (26-30). Examples of other patient-related factors that affect the accuracy of blood pressure measurement include talking during the procedure (+17/+13 mm Hg) and acute exposure to cold (+11/+8 mm Hg). Additional provider-related errors include failure to support the arm (+2/+2 mm Hg), using an inappropriate cuff size (+8/+8 mm Hg if the cuff is too small) (31-33), and terminal digit preference (rounding up or down to the nearest 0 or 5) (6).
3. Four approaches can be used to assess BP (see text for definitions):
i. Office BP measurement (OBPM): Measurement using electronic (oscillometric) upper arm devices is preferred over auscultation (Grade C) (unless specified otherwise, henceforth OBPM refers to electronic (oscillometric) measurement). When using mean OBPM, an SBP ≥140 mm Hg or a DBP ≥90 mm Hg is high, and an SBP between 130-139 mm Hg and/or a DBP between 85 and 89 mm Hg is high-normal (Grade C).
Over the past century, auscultation has been the predominant blood pressure measurement method. If auscultatory blood pressure is performed properly (i.e., using standardized methodology), it correlates well with ambulatory measurements and can predict target organ changes (34-36). However, ‘real world’ routine office auscultatory measurement, when performed by both in nurses and physicians, is consistently inaccurate because standardized methodology is simply not followed (5,13-15,18,20,37-39). The BP obtained in routine clinical practice is on average 9/6 mm Hg higher than standardized measurements (40,41). Unfortunately repeated educational programs to improve blood pressure measurement do not produce sustainable improvements in technique (14,42-47). The widespread removal of mercury from clinics and hospitals has created an additional source of error, as replacement anaeroid devices commonly used for auscultation are inaccurate unless regularly calibrated (which is not often done).
For these reasons, the Task Force strongly encourages the use of validated electronic digital oscillometric devices. These devices are pre-programmed to take either single measurements or an automated series of measurements with averaging of the results. Electronic oscillometric devices minimize or eliminate many auscultation-induced errors, including those related to provider hearing deficits, terminal digit preference (rounding the reading to 0 or 5) and rapid deflation (48,49). Many devices for both clinical and public use have been found to be accurate and reproducible when compared to research-quality OBP (www.dableducational.com).
It is important to note that, although OBPM is often used for initially assessing BP in a given individual, the diagnosis should be confirmed by performing out-of-office measurement (if possible). Further details are provided in the recommendations that follow.
Atrial fibrillation poses unique challenges in terms of blood pressure measurement because it leads to random fluctuations in stroke volume and pulse pressure, which affects the accuracy of both auscultation and oscillometric measurement (5,50). For these reasons, performing multiple measurements to obtain consistent results is important in patients with atrial fibrillation. Notably, newer oscillometric devices have produced more accurate readings in patients with atrial fibrillation (51-53).
ii. Automated Office Blood Pressure Measurement (AOBP): When using AOBP (see Supplemental Table S2, AOBP), a displayed mean SBP ≥135 mm Hg or DBP ≥85 mm Hg is high (Grade D).
Certain fully automated BP measuring devices intended for clinic use are capable of taking repeated BP measurements when a patient is alone in the examining room (54,55). Using repeat measure devices in this manner has been referred to as automated office BP (AOBP) measurement. AOBP is a specific type of OBPM designed to overcome some of the limitations of OBPM. Multiple (3-6, depending on the device) pre-programmed measurements, usually spaced one minute apart over 4-7 minutes, are taken while the patient is alone in a quiet room. Recommendations for measurement standardization related to patient position and proper cuff size also apply to AOBP.
AOBP provides a more standardized assessment of blood pressure compared to routine manual office measurement and is more reproducible than manual office measurement. Because the patient is left alone, error introduced by conversing with the patient during the measurement process is eliminated (56,57). Importantly, compared to manual office measurements, AOBP has repeatedly been demonstrated to correlate more closely with daytime ABPM (41,58-62). Furthermore, use of AOBP reduces office-induced blood pressure increases (i.e., white coat effect) and is associated with a lower prevalence of masked hypertension (58,61). On the basis of the above evidence the CHEP Recommendations Task Force endorsed the use of AOBP for office blood pressure measurement in 2011 (63).
Several studies (40,60,61) have shown that mean AOBP readings are comparable to daytime ambulatory BP readings, therefore a mean AOBP of SBP ≥135 mm Hg or DBP ≥85 mm Hg is considered high.
There are no studies that directly relate AOBP readings to the occurrence of cardiovascular events. Three cross-sectional studies demonstrating high correlations between AOBP levels and surrogate measures of end-organ damage (left ventricular mass index, urinary albumin excretion, and carotid intima-medial thickness) have been published (64-66). Further research is required to determine whether AOBP measurements can predict target organ damage and cardiovascular events better than manual office readings. For this reason, high AOBP readings should be confirmed using out-of-office measurement before making a diagnosis of hypertension.
Several AOBP devices have been independently validated for clinical accuracy including the BpTRU automatic BP monitor (BpTRU Medical Devices, Canada – the most commonly used device in Canada), the BPM-100 electronic oscillometric office BP monitor, the Omron office digital BP HEM-907 monitor (Omron Canada Inc, Canada), and the Microlife WatchBP Office professional device (Microlife AG Swiss Corporation, Switzerland) (60,67-69).
iii. Ambulatory BP Measurement (ABPM): Using ABPM (see Recommendations in Section VIII, ABPM), patients can be diagnosed as hypertensive if the mean awake SBP is ≥135 mm Hg or the DBP is ≥85 mm Hg or if the mean 24-hour SBP is ≥130 mm Hg or the DBP is ≥80 mm Hg (Grade C).
These widely accepted 24-hour ambulatory blood pressure thresholds have been derived from prognostic studies examining cardiovascular morbidity and mortality endpoints (70-75).
iv. Home BP monitoring (HBPM): (see Recommendations in Section VII, HBPM) Patients can be diagnosed as hypertensive if the mean SBP is ≥135 mm Hg or the DBP is ≥85 mm Hg (Grade C). If the OBPM is high and the mean home BP is <135/85 mm Hg, it is advisable to either repeat home monitoring to confirm the home BP is <135/85 mm Hg or perform 24-hour ABPM to confirm that the mean 24-hour ABPM is <130/80 mm Hg and the mean awake ABPM is <135/85 mm Hg before diagnosing white coat hypertension (Grade D).
The threshold above which home/self BP values should be considered elevated is 135/85 mm Hg. This is supported by prognostic studies showing an increased risk of cardiovascular events above or near this threshold (76-84).
The need to further assess patients when a home BP measurement is less than 135/85 mm Hg (and white coat effect is suspected) is based on the Treatment of Hypertension Based on Home or Office Blood Pressure (THOP) trial, where home/self BP monitoring was specific (89%) but not sensitive (68%) in its ability to detect white coat hypertension (85-87). Other studies also support this recommendation. In particular, this recommendation applies when the home BP is borderline normal. Further assessment can be done by either repeating home BP or performing ABPM.
|Table 1. Standardized protocol for ambulatory BP monitoring (Grade D)|
|BP, blood pressure; SBP, systolic blood pressure.|
- Lindsay P, Conner Gorber S, Joffres M, et al. Recommendations on screening for high blood pressure in Canadian adults. Can Fam Physician 2013;59:927-33.
- Prospective Studies Collaboration. Age-specific relevance of usual blood pressure to vascular mortality: a meta-analysis of individual data for one million adults in 61 prospective studies. Lancet 2002;360:1903-13.
- Blood Pressure Lowering Treatment Trialists Collaboration. Blood pressure-lowering treatment based on cardiovascular risk: a meta-analysis of individual patient data. Lancet 2014;384:591-8.
- Kannel WB, Neaton JD, Wentworth D, et al. Overall and coronary heart disease mortality rates in relation to major risk factors in 325,348 men screened for the MRFIT. Multiple Risk Factor Intervention Trial. Am Heart J 1986;112:825-6.
- McKay DW, Campbell NR, Parab LS, Chockalingam A, Fodor JG. Clinical assessment of blood pressure. J Hum Hypertens 1990;4:639-45.
- McAlister FA, Straus SA. Measurement of blood pressure: an evidence based review. BMJ 2001;322:908-11.
- Pickering TG, Hall JE, Appel LJ, et al. Recommendations for Blood Pressure Measurement in Humans and Experimental Animals: Part 1: Blood Pressure Measurement in Humans: A Statement for Professionals From the Subcommittee of Professional and Public Education of the American Heart Association Council on High Blood Pressure Research. Circulation 2005;111:697-716.
- Rouse A, Marshall T. The extent and implications of sphygmomanometer calibration error in primary care. J Hum Hypertens 2001;15:587-91.
- Kaczorowski J, Chambers LW, Dolovich L, et al. Improving cardiovascular health at population level: 39 community cluster randomised trial of Cardiovascular Health Awareness 13 Program (CHAP). BMJ 2011;342:d442.
- Campbell NR, Myers MG, McKay DW. Is usual measurement of blood pressure meaningful? Blood Press Monit 1999;4:71-76.
- Campbell NRC, Culleton BW, McKay DW. Misclassification of blood pressure by usual measurement in ambulatory physician practices. Am J Hypertens 2005;18:1522-1527.
- Jones DW, Appel LJ, Sheps SG, Rocella EJ, Lenfant C. Measuring blood pressure accurately: New and persistant challenges. JAMA 2003;289:1027-30.
- Armstrong RS. Nurses’ knowledge of error in blood pressure measurement technique. Int J Nurs Pract 2002;8:118-26.
- Kemp F, Foster C, McKinlay S. How effective is training for blood pressure measurement? Prof Nurse 1994;9:521-4.
- Gillespie A, Curzio J. Blood pressure measurement: assessing staff knowledge. Nurs Stand 1998;12:35-7.
- Campbell NRC, McKay DW, Chockalingam A, Fodor JG. Errors in assessment of blood pressure: Patient Factors. Can J Public Health 1994;85:S12-S17.
- Campbell NRC, McKay DW, Chockalingam A, Fodor JG. Errors in assessment of blood pressure : Sphygmomanometers and blood pressure cuffs. Can J Public Health 1994;85:S22-S25.
- Dreveniiorn E, Hakansson A, & Petersson K. Blood pressure measurement – an observational study of 21 public health nurses. J Clin Nurs 2001;10:189-194.
- Feher M, Harris-St John K, & Lant A. Blood pressure measurement by junior hospital doctors – a gap in medical education? Health Trends 1992;24:59-61.
- Gleichmann SI, Gleichmann UM, Mannebach HJ, Mellwig K-P, Philippi H-H. Educating nurses in blood pressure measurement and hypertension control. J Hypertens 1989;7(S3):S99-S102.
- Netea RT, Lenders JW, Smits P, Thien T. Arm position is important for blood pressure measurement. J Hum Hypertens 1999;13:105-9.
- Netea RT, Bijlstra PJ, Lenders JW, Smits P, Thien T. Influence of the arm position on intra-arterial blood pressure measurement. J Hum Hypertens 1998;12:157-60.
- Hemingway TJ, Guss DA, Abdelnur D. Arm position and blood pressure measurement. Ann Intern Med 2004;140:74-5.
- Waal-Manning HJ, Paulin JM. Effects of arm position and support on blood pressure readings. J Clin Hypertens 1987;3:624-30.
- Webster J, Newnham D, Petrie JC and Lovell HG. Influence of arm position on measurement of blood pressure. BMJ 1984;288:1574-1575.
- Peters GL, Binder SK, Campbell NR. The effect of crossing legs on blood pressure: a randomized single-blind cross-over study. Blood Press Monit 1999;4:97-101.
- Foster-Fitzpatrick L, Ortiz A, Sibilano H, Marcantonio R, Braun LT. The effects of crossed leg on blood pressure measurement. Nurs Res 1999;48:105-8.
- Keele-Smith R, Price-Daniel C. Effects of crossing legs on blood pressure measurement. Clin Nurs Res 2001;10:202-13.
- Pinar R, Pinar R, Ataalkin S, Watson R. Effects of crossed leg on blood pressure in hypertensive patients. J Clin Nurs 2010;19:1284-8.
- Adiyaman A, Tosun N, Elving LD, Deinum J, Lenders JW, Thien T. The effect of crossing legs on blood pressure. Blood Press Monit 2007;12:189-193.
- Sprafka JM, Strickland D, Gómez-Marín O, Prineas RJ. The effect of cuff size on blood pressure measurement in adults. Epidemiology 1991;2:214-7.
- Iyriboz Y, Hearon CM, Edwards K. Agreement between large and small cuffs in sphygmomanometry: a quantitative assessment. J Clin Monit 1994;10:127-33.
- Geddes LA, Whistler SJ. The error in indirect blood pressure measurement with the incorrect size of cuff. Am Heart J 1978;96:4-8.
- Lamarre-Cliche M, Cheong NNG, Larochelle P. Comparative assessment of four blood pressure measurement methods in hypertensives. Can J Cardiol 2011;27:455-60.
- Fagard R, Staessen J, Thijs L, Amery A. Multiple standardized clinic blood pressure may predict left ventricular mass as well as ambulatory monitoring. Am J Hypertens 1995;8:533-40.
- Woodiwiss AJ, Molebatsi N, Maseko MJ, Libhaber E, Libhaber C, Majane OH, et al. Nurse-recorded auscultatory blood pressure at a single visit predicts target organ changes as well as ambulatory blood pressure. J Hypertens 2009;27:287-97.
- Villegas I, Arias IC, Botero A, Escobar A. Evaluation of the technique used by health-care workers for taking blood pressure. Hypertension 1995;26:1204-6.
- McKay DW, Raju MK, Campbell NRC. Assessment of blood pressure measuring techniques. Med Educ 1992;26:208-12.
- Veiga EV, Nogueira MS, Carnio EC, Marques S, Lavrador MAS, Alves de Moraes S, et al. Assessment of the techniques of blood pressure measurement. Arq bras de cardiol 2003;80:89-93.
- Myers MG, Valdivieso M, Kiss A. Consistent relationship between automated office blood pressure recorded in different settings. Blood Press Monit 2009;14:108-11.
- Myers MG, Kaczorowski J, Dawes M, Godwin M. Automated office blood pressure measurement in primary care. Canadian Family Physician 2014;60:127-32.
- Rabbia F, Testa E, Rabbia S, Praticò S, Colasanto C, Montersino F, et al. Effectiveness of blood pressure educational and evaluation program for the improvement of measurement accuracy among nurses. J Ital Soc Hypertens 2013;20:77-80.
- Allaire BT, Trogdon JG, Egan BM, Lackland DT, Masters D. Measuring the impact of a continuing medical education program on patient blood pressure. J Clin Hypertens 2011;13:517-22.
- Bottenberg MM, Bryant GA, Haack SL, North AM. Assessing pharmacy students’ ability to accurately measure blood pressure using a blood pressure simulator arm. Am J Pharm Educ 2013;77:98.
- Dickson BK, Hajjar I. Blood pressure measurement education and evaluation program improves measurement accuracy in community-basec nurses: a pilot study. J Am Acad Nurs Pract 2007;19:93-102.
- Gordon CJ, Frotjold A, Fethney J, Green J, Hardy J, Maw M, et al. The effectiveness of simulation-based blood pressure training in preregistration nursing students. J Soc Stim Health 2013;8:335-40.
- Mujtaba SH, Ashraf T, Anjum Q. Improving general practitioners’ knowledge regarding blood pressure measurement in selected cities of Pakistan through workshop. Asia Pacif J Pub Health 2013;25:84-91.
- Myers MG, Godwin M, Dawes M, Kiss A, Tobe SW, Kaczorowski J. Measurement of blood pressure in the office: recognizing the problem and proposing the solution. Hypertension 2010;55:195-200.
- Stergiou GS, Parati G, Asmar R, O’Brien E. Requirements for professional office blood pressure monitors. J Hypertens 2012;30:537-42.
- Ochiai H, Mitake A, Miyata T, Ishigami T, Ashino K, Sumita S, et al. Assessment of auscultatory blood pressure measurements versus intra-arterial pressure in patients with atrial fibrillation. J Cardiol 1997;29:331-6.
- Kollias A, Stergiou GS. Automated measurement of office, home and ambulatory blood pressure in atrial fibrillation. Clin Exper Pharm & Physiol 2014;41:9-15.
- Stergiou GS, Kollias A, Karpettas N. Does atrial fibrillation affect the automated oscillometric blood pressure measurement? Hypertension 2013;62:e37.
- Stergiou GS, Kollias A, Destounis A, Tzamouranis D. Automated blood pressure measurement in atrial fibrillation: a systematic review and meta-analysis. J Hypertens 2012;30:2074-82.
- Myers MG. Automated blood pressure measurement in routine clinical practice. Blood Press Monit 2006;11:59-62.
- Myers MG, Godwin M. Automated measurement of blood pressure in routine clinical practice. J Clin Hypertens 2007;9:267-70.
- Myers MG. Replacing manual sphygmomanometers with automated blood pressure measurement in routine clinical practice. Clin Exp Physiol Pharmacol 2014;41:46-53.
- Myers MG. Eliminating the human factor in office blood pressure measurement. J Clin Hypertens 2014;16:83-6.
- Myers MG, Valdivieso M, Kiss A. Use of automated office blood pressure measurement to reduce the white coat response. J Hypertens 2009;27:280-6.
- Godwin M, Birtwhistle R, Delva D, Lam M, Casson I, MacDonald S, et al. Manual and automated office measurements in relation to awake ambulatory blood pressure monitoring. Fam Pract 2011;28:110-7.
- Beckett L, Godwin M. The BpTRU automatic blood pressure monitor compared to 24 hour ambulatory blood pressure monitoring in the assessment of blood pressure in patients with hypertension. BMC Cardiovasc Disord 2005;5:18.
- Myers MG. A proposed algorithm for diagnosing hypertension using automated office blood pressure measurement. J Hypertens 2010;28:703-708.
- Myers MG, Godwin M, Dawes M, Kiss A, Tobe SW, Kaczorowski J. Conventional versus automated measurement of blood pressure in the office (CAMBO) trial. Fam Pract 2012;29(4):376-82.
- Rabi DM, Daskalopoulou SS, Padwal RS, Khan NA, Grover SA, Hackam DG, et al. The 2011 Canadian Hypertension Education Program recommendations for the management of hypertension: blood pressure measurement, diagnosis, assessment of risk, and therapy. Can J Cardiol 2011;27:415-33.e1-2.
- Andreadis EA, Agaliotis GD, Angelopoulos ET, Tsakanikas AP, Chaveles IA, Mousoulis GP. Automated office blood pressure and 24-h ambulatory measurements are equally associated with left ventricular mass index. Am J Hypertens 2011;24:661-6.
- Campbell NRC, McKay DW, Conradson H, Lonn E, Title LM, Anderson T. Automated oscillometric blood pressure versus auscultatory blood pressure as a predictor of carotid intima-medial thickness in male firefighters. J Hum Hypertens 2007;21:588-90.
- Andreadis EA, Agaliotis GD, Angelopoulos ET, Tsakanikas AP, Kolyvas GN, Mousoulis GP. Automated office blood pressure is associated with urine albumin excretion in hypertensive subjects. Am J Hypertens 2012;25:969-73.
- Wright JM, Mattu GS, Perry Jr TL, et al. Validation of a new algorithm for the BPM-100 electronic oscillometric office blood pressure monitor. Blood Press Monit 2001;6:161-5.
- White WB, Anwar YA. Evaluation of the overall efficacy of the Omron office digital blood pressure HEM-907 monitor in adults. Blood Press Monit 2001;6:107-10.
- Stergiou GS, Tzamouranis D, Protogerou A, Nasothimiou E, Kapralos C. Validation of the Microlife Watch BP office professional device for office blood pressure measurement according to the international protocol. Blood Press Monit 2008;13:299-303.
- Verdecchia P, Reboldi G, Porcellati, et al. Risk of cardiovascular disease in relation to achieved office and ambulatory blood pressure control in treated hypertensive subjects. J Am Coll Cardiol 2002;39:878-85.
- Ohkubo T, Imai Y, Tsuji I. Prediction of mortality by ambulatory blood pressure monitoring versus screening blood pressure measurements: a pilot study in Ohasama. J Hypertens 1997;15:357-64.
- Verdecchia P, Porcellati C, Schillaci G, Borgioni C, Ciucci A, Battistelli M, et al. Ambulatory blood pressure. An independent predictor of prognosis in essential hypertension. Hypertension 1994;24:793-801.
- O’Brien E, Parati G, Stergiou G, Asmar R, Beilin L, Bilo G, Clément D, de la Sierra A, de Leeuw P, Dolan E, Fagard R, Graves J, Head G, Imai Y, Kario K, Lurbe E, Mallion JM, Mancia G, Mengden T, Myers M, Ogedegbe G, Ohkubo T, Omboni S, Palatini P, Redon J, Ruilope LL, Shennan A, Staessen JA, vanMontfrans G, Verdecchia P, Waeber B, Wang J, Zanchetti A, Zhang Y. European Society of Hypertension position paper on ambulatory blood pressure monitoring. J Hypertens 2013;31:1731-1768.
- Ohkubo T, Imai Y, Tsuji I, etal. Reference values for 24-hour ambulatory blood pressure monitoring based on a prognostic criterion: the Ohasama Study. Hypertension 1998;32:255-9.
- Hansen TW, Kikuya M, Thijs L, et al. Prognostic superiority of daytime ambulatory over conventional blood pressure in four populations: a meta-analysis of 7,030 individuals. J Hypertens 2007;25:1554-64.
- Bobrie G, Chatellier G, Genès N, Clerson P, Vaur L, Vaisse B, et al. Cardiovascular prognosis of “Masked Hypertension” detected by blood pressure self-measurement in elderly treated hypertensive patients. JAMA 2004;291:1342-9.
- Asayama K, Ohkubo T, Kikuya M, et al. Prediction of stroke by self-measurement of blood pressure at home versus casual screening blood pressure measurement in relation to the Joint National Committee 7 classification: The Ohasama study. Stroke 2004;35:2356-61.
- Ohkubo T, Asayama K, Kikuya M, et al; Ohasama Study. How many times should blood pressure be measured at home for better prediction of stroke risk? Ten-year follow-up results from the Ohasama study. J Hypertens 2004;22:1099-104.
- Tsuji I, lmai Y, Nagai K, et al. Proposal of reference values for home blood pressure measurement: prognostic criteria based on a prospective observation of the general population in Ohasama, Japan. Am J Hypertens 1997;10:409-18.
- Thijs L, Staessen JA, Celis H, et al. Reference values for self-recorded blood pressure: a meta-analysis of summary data. Arch Intern Med 1998;158:481-8.
- Ohkubo T, Imai Y, Tsuji I, et al. Home blood pressure measurement has a stronger predictive power for mortality than does screening blood pressure measurement: a population- based observation in Ohasama, Japan. J Hypertens 1998;16:971-5.
- Sakuma M, Imai Y, Tsuji I, et al. Predictive value of home blood pressure measurement in relation to stroke morbidity: a population-based pilot study in Ohasama, Japan. Hypertens Res 1997;20:167-74.
- de Gaudemaris R, Chau NP, Mallion J-M. Home blood pressure: variability, comparison with office readings and proposal for reference values. J Hypertens 1994;12:831-8.
- Imai Y, Satoh H, Nagai K. Characteristics of a community-based distribution of home blood pressure in Ohasama in northern Japan. J Hypertens 1993;11:1441-9.
- Hond ED, Celis H, Fagard R, et al; THOP investigators. Self- measured versus ambulatory blood pressure in the diagnosis of hypertension. J Hypertens 2003;21:717-22.
- Warren RE, Marshall T, Padfield PL, Chrubasik S. Variability of office, 24-hour ambulatory, and self-monitored blood pressure measurements. Br J Gen Pract 2010;60:675-80.
- Coll de Tuero G, Llibre JB, Poncelas AR, Saumell CR, Saez M, Boreu QF, et al. Isolated clinical hypertension diagnosis: self-home BP, ambulatory BP monitoring, or both simultaneously? Blood Press Monit 2011;16:11-5.