Table 1

Survey methods, by country

CountryYears of surveySamplingnAge rangeResponse rate
England2006Multistage687320–7968% household response rate, 88% individual response rate in co-operating households and 66% with nurse visit (examination response rate).
Canada2007–2009Multistage348520–79Household response rate=70%
Individual response rate to the household questionnaire=88% Examination response rate=85%

USA2007–2010Multistage10 00320–79Interview response rate=79%
Examination response rate=76%
93% of those examined had ≥2 blood pressure measurements
CountryBlood pressure deviceTechnicianNo of blood pressure measuresStudy protocol used
EnglandOmron HEM 907Nurse3Mean of second and third measures taken 1 min apart after 5 min rest
CanadaBp TRU BP-300*Health measures specialists6Average of last 5 of 6 measures taken 1 min apart after a 5 min rest period
USACalibrated V-Lok cuff, Latex Inflation Bulb, Air-Flo Control Valve. Baumanometer calibrated mercury wall model.Physician3Mean of second and third measurementS taken 30 s apart after resting quietly in a sitting position for 5 min†
  • All valid blood pressure readings excluding pregnant women.

  • *Bp TRU BP-100 used during home visits for respondents who were unable or unwilling to go at the mobile clinic.

  • †US NHANES survey protocol: After resting quietly in a sitting position for 5 min, three consecutive blood pressure readings were obtained. If a blood pressure measurement was interrupted or incomplete, a fourth attempt could be made.