Resting blood pressure and heart rate measurement in the Canadian Health Measures Survey, cycle 1.
BACKGROUND
Directly measured blood pressure (BP) data have not been collected in Canada since the Canadian Heart Health Surveys, conducted between 1985 and 1992. Because hypertension is often asymptomatic, a large proportion of those with the condition are unaware of it.


METHODS
These analyses use BP and heart rate (HR) data from cycle 1 of the 2007-2009 Canadian Health Measures Survey (CHMS) for respondents aged 6 to 79 years. Methods and quality assurance and control procedures are explained. Logistical and feasibility issues that arose during data collection are discussed. The reasons for repeating a series of measures are given. Between- and within- series variations and inter-tester variability are assessed.


RESULTS
The BP and HR of almost all respondents who attended the examination centre were measured. Only one series of measurements was taken for 88% of respondents. The series was repeated for around 5% with variability in their BP or HR measurements. About 3% had HR or BP values above the screening cut-offs for the fitness tests. Almost 35% of respondents with HR or BP values above the screening cut-offs after their first series had values below the cut-points after the second series; a further 3% had values below after the third series. Within a series of six measurements, BP decreased until about the fourth measure, after which it remained stable. Mean BP and HR values indicated no inter-tester variability.


CONCLUSIONS
The protocol for measuring BP and HR by oscillometry in the CHMS appears to have produced reliable estimates. No benefit to repeating the series of six measurements a third time for screening purposes is evident. Four measurements may be sufficient to provide reliable BP and HR data. Oscillometry appears to eliminate inter-tester variability.
Bryan
Shirley
S
Physical Health Measures Division, Statistics Canada, Ottawa, Ontario K1A 0T6. Shirley.Bryan@statcan.gc.ca
Saint-Pierre Larose
Mathieu
M
Campbell
Norm
N
Clarke
Janine
J
Tremblay
Mark S
MS
D000293:Adolescent; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000295:instrumentation / Q000592:standards*; D002170:Canada; D002648:Child; D016001:Confidence Intervals; D003971:Diastole; D005240:Feasibility Studies; D005260:Female; D006306:Health Surveys; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009991:Oscillometry / Q000592:standards; D015203:Reproducibility of Results; D012146:Rest / Q000502:physiology*; D011795:Surveys and Questionnaires; D013599:Systole; D055815:Young Adult