***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    ***EXAMPLES*** 
    Input: Background —The prevalence and clinical significance of isolated office ( or white coat ) hypertension is controversial , and population data are limited . We studied the prevalence of this condition and its association with echocardiographic left ventricular mass in the general population of the PAMELA ( Pressione Arteriose Monitorate E Loro Associazioni ) Study . Methods and Results —The study involved a large , r and omized sample ( n=3200 ) representative of the Monza ( Milan ) population , 25 to 74 years of age . Participants in the study ( 64 % of the sample ) underwent measurements of office , home , 24-hour ambulatory blood pressure , and echocardiography . Isolated office hypertension was defined as systolic or diastolic values ≥140 mm Hg or ≥90 mm Hg , respectively . Home and ambulatory normotension were defined according to criteria previously established from the PAMELA Study , for example , < 132/83 mm Hg ( systolic/diastolic ) for home and 125/79 mm Hg for 24-hour average blood pressure . Treated hypertensive subjects were excluded from analysis that was made on a total of 1637 subjects . Depending on normotension being established on systolic or diastolic blood pressure measured at home or over 24 hours , the prevalence of isolated office hypertension ranged from 9 % to 12 % . In these subjects , left ventricular mass index was greater ( P < 0.01 ) than in subjects with normotension both in and outside the office . This was the case also for prevalence of left ventricular hypertrophy . Left ventricular mass index and hypertrophy were similarly greater in subjects found to have normal office but elevated home or ambulatory blood pressure ( ≈10 % of the population ) . Conclusions —Isolated office hypertension has a noticeable prevalence in the population and is accompanied by structural cardiac alterations , suggesting that it is not an entirely harmless phenomenon . This is the case also for the opposite condition , that is , normal office but elevated home or ambulatory blood pressure , which implies that limiting blood pressure measurements to office values may not suffice in identification of subjects at risk Abstract Objective : To assess alternatives to measuring ambulatory pressure  , whichbest predicts response to treatment and adverse outcome . Setting : Three general practice s in Engl and Design : Validation study Participants : Patients with newly diagnosed high or borderline high bloodpressure ; patients receiving treatment for hypertension but with poor control . Main outcome measures : Overall agreement with ambulatory pressure ; prediction of high ambulatory pressure ( > 135/85 mm Hg ) and treatment thresholds . Results : Readings made by doctors were much higher than ambulatory systolic pressure ( difference 18.9 mm Hg , 95 % confidence interval 16.1 to 21.7 ) , as were recentreadings made in the clinic outside research setting s ( 19.9 mm Hg,17.6 to 22.1 ) . This applied equally to treated patients with poor control ( doctor v ambulatory21.4 mm Hg , 17.3 to 25.4 ) . Doctors ' and recent clinic readings ranked systolic pressure poorly compared with ambulatory pressure and other measurements ( doctor r=0.46 ; clinic 0.47 ; repeated readings by nurse 0.60 ; repeated self measurement 0.73 ; home readings 0.75 ) and were not specific at predicting high blood pressure(doctor 26 % ; recent clinic 15 % ; nurse 72 % ; patient in surgery 81 % ; home 60 % ) , with poor likelihood ratios for a positive test ( doctor 1.2 ; clinic 1.1 ; nurse 2.1 , patient in surgery 4.7 ; home 2.2 ) . Nor were doctor or recent clinic measures specific in predicting treatment thresholds . Conclusion : The “ white coat ” effect is important in diagnosing and assessing control of hypertension in primary care and is not a research artefact . If ambulatory or home measurements are not available , repeated measurements by the nurse or patient should result in considerably less unnecessary monitoring , initiation , or changing of treatment . It is time to stop using high blood pressure readings documented by general practitioners to make treatment BACKGROUND Ambulatory blood pressure monitoring was introduced more than 40 years ago and is accepted as a clinical ly useful method to evaluate the white coat effect in patients with suspected and established hypertension . AIM To study the differences between  blood pressure readings  taken in the physician 's office in the primary healthcare setting , and ambulatory readings , and to find possible predictors . DESIGN OF STUDY Prospect i ve study . SETTING Two primary healthcare centres in Norway . METHOD The study included 221 patients , 107 of whom were on antihypertensive treatment , and 114 of whom were under investigation for possible hypertension . Differences between blood pressure readings taken in the physician 's office and ambulatory readings were calculated . Independent predictors for the white coat effect were calculated using linear regression analysis . RESULTS The difference between blood pressure readings taken in the office and ambulatory readings was 27 mmHg systolic and 11 mmHg diastolic . For the systolic readings , the following factors were independent predictors of the amount of the white coat effect : mean blood pressure , age , history of smoking , family history of cardiovascular disease , and antihypertensive treatment . For the diastolic readings , they were : mean blood pressure , history of smoking , and sex of the patient ( with this being most significant for women ) . CONCLUSION  Ambulatory blood pressure measurement is of significant value in identifying patients with white coat hypertension . It can be an important supplement for use in the diagnosis and follow-up of patients with hypertension in general practice Patients receiving drug therapy for hypertension in the tertiary care setting frequently exhibit higher office readings compared to ambulatory blood pressure values ( white coat effect ) . In this study , the prevalence of a white coat effect was determined in an unselected population of 147 hypertensive patients receiving treatment from their family physicians in the community . The proportion of patients with a white coat effect ( defined as office - ambulatory blood pressure > or = 20/10 mm Hg ) was significantly ( P < .001 ) higher when based upon the family physician 's routine blood pressure readings ( 91/147 ) , compared to special readings taken by the family physician for the study ( 54/147 ) or readings taken by a research nurse ( 30/147 ) . There was a higher correlation ( P < .05 ) between the ambulatory systolic blood pressure and the  nurse 's readings  ( r = 0.62 ) or special physician 's readings ( r = 0.55 ) v the routine physician 's readings ( r = 0.34 ) . Left ventricular mass index as measured by echocardiography correlated ( P < .01 ) with the special physician ( r = 0.27 ) , nurse ( r = 0.23 ) , and ambulatory systolic blood pressure readings ( r = 0.24 ) , but not with the routine physician 's readings ( r = 0.06 ) . A white coat effect is frequently present in treated hypertensive patients when blood pressure is recorded by family physicians in routine clinical practice Background Guidelines recommend that blood pressure ( BP ) should be lowered in hypertensive patients to prevent cardiovascular accidents . Management of antihypertensive treatment by general practitioners is usually based on office measurements , which may not allow an assessment of BP control over 24 h , which requires ambulatory BP monitoring ( ABPM ) to be implemented . This is rarely done in general practice , and limited information is available on the consistency between the evaluations of the response to treatment provided by office measurement and by ABPM in this setting . Aim To assess concordance between office BP measurements and ABPM-based estimates of hypertension control in a general practice setting . Design of study Prospect i ve , comparative between techniques . Setting General practice . Methods Seventy-eight general practice s , representative of all Italian regions , participated in this study by recruiting sequential hypertensive adults on stabilized treatment , who were subdivided into even groups with office BP , respectively , controlled or noncontrolled by treatment . In each individual , ABPM was applied by the general practitioner after appropriate training , and 24-h ABP values were defined as controlled or not according to current guidelines . Concordance between office and ABPM evaluation of BP control was assessed with κ statistics . Positive and negative predictive values of office measurement  versus ABPM were estimated . Results Between July 2005 and November 2006 , 190 general practitioners recruited 2059 hypertensive patients based on office BP measurements ; in 1728 patients , a 24-h ABPM  was performed , yielding 1524 recordings considered as valid for further analysis . The agreement between the assessment of BP control by office measurement and by ABPM was poor ( κ = 0.120 ) , with office measurements showing a satisfactory positive predictive value ( 0.842 ) and a poor negative predictive value ( 0.278 ) ; the situation was worse in patients with three or more among the following features : male sex , age of at least 65 years , alcohol consumption , diabetes , and obesity ( negative predictive value = 0.149 ) . Conclusion In general practice , the agreement between assessment of BP control by treatment provided by office and ambulatory BP measurements is better in patients of ‘ uncontrolled ’ office BP than in ‘ controlled ’ office BP patients . This emphasizes the need for the larger use of out-of-office BP monitoring in a general practice setting , in particular , in patients considered as ‘ controlled ’ during consultation Ambulatory blood pressure monitoring ( ABPM ) is being increasingly used in general practice . There is at present little published evidence regarding the clinical utility of ABPM in the care of patients with established hypertension in this setting . We examined this issue by undertaking ABPM in a group of patients with established hypertension . 40 patients ( aged 33–60 years ) currently being treated for hypertension were r and omly selected from a general practice list and underwent a single 24-hour ABPM study .  ABPM  values were compared with clinic blood pressure ( CBP ) values obtained on the day of monitoring together with previous readings taken by the general practitioner ( GP ) . In the case of mean arterial pressure , 24-hour , awake and asleep ABPM values were found to underestimate CBP values by 14 mmHg ( 95 % confidence interval 11–16 mmHg ) , 9 mmHg ( 95 % Cl 6–12 mmHg ) and 24 mmHg ( 95 % Cl 21–27 mmHg ) , respectively . When used to classify blood pressure control , ABPM values produced equivalent results to CBP except by the criterion of BP load , for which 24-hour ABPM showed a higher rate of unsatisfactory control . 5 patients classified by CBP to have satisfactory BP control according to current international guidelines were found to have unsatisfactory BP control by ABPM . This study demonstrates the potential value of ABPM in patients with essential hypertension in a general practice setting . ABPM provided information over and above that obtained by CBP in a substantial proportion of patients 
    Output:
    
Conclusion Likelihood ratios show that isolated BP measurement in the office does not confirm or rule out the presence of poor BP control .
Likelihood of underestimating or overestimating BP control is high when relying on in-office BP measurement alone