This topic refers to the diastolic and systolic measures of blood pressure, which were measured by the interviewers during the interview.
Information was obtained for persons aged 18 years and over, who agreed to have their measurements taken, in the 2014-15 NHS. Data was imputed (for further information see Imputation section) for those who did not have their measurements taken. This differs to the 2011-13 AHS where information was obtained for all persons aged 5 years and over who agreed to have their measurements taken.
Information about blood pressure was published in the National Health Survey: First Results, 2014-15 based on a sample of 14,564 people aged 18 years and over.
Blood pressure measurements were taken towards the end of the survey and were voluntary. Respondents were invited to sit down and extend and relax their left arm, with their palm facing upwards. Interviewers were given a choice of three different sized cuffs to select from depending on respondent size. All measurements were taken on the left arm, unless there was a prohibitive reason such as an injury. Interviewers undertook two blood pressure readings using an automated blood pressure monitor in which systolic and diastolic pressures were displayed. If there was a significant difference (greater than 10 mmHg) between the readings, for either the diastolic or systolic readings, the CAI instrument would prompt for a third reading.
The follow blood pressure ranges were used to categorise blood pressure for persons aged 18 years and over.
Blood pressure ranges
|Normal - high
|From 120/80 to <140/90
|From 140/90 to <160/110
|From 160/100 to <180/110
Note: if either the systolic or diastolic reading was placed in a higher blood pressure level category, then the respondent was placed in that higher category.
The derived systolic and diastolic data items involve a combination of up to two readings. Unless there was only one reading, the first reading was generally not used. The majority of participating respondents had two readings taken, and in these cases the second reading was used for the measures of systolic and diastolic pressure. When a third reading was required to be taken, the second and third readings were averaged unless the third reading differed by 20 mmHg or more. If all readings had a variation of 20 mmHg or greater the derived measurement items were recorded as invalid readings.
The questionnaire, data items and related output categories for this topic are available in pdf/Excel spreadsheet format from the Downloads page of this product.
Points to be considered in interpreting data for this topic include the following:
- Non-response rates for physical measurements were higher in 2014-15 than in the 2011-13 AHS. In 2014-15, 24.3% of respondents aged 18 years and over did not have their blood pressure measured. For these people, blood pressure was imputed. Blood pressure data presented in the 2014-15 NHS includes both measured and imputed data.
- An investigation was undertaken to determine whether the characteristics of the people who were measured differed from those who were not measured. This investigation looked at variables such as smoking status, self-assessed health, employment status, marital status, country of birth, self perceived body mass, level of exercise and whether or not has high cholesterol (as a long-term health condition) and found no differences. While there were some differences in age, sex and part of state, these were taken account of in the weighting process. As a result of this investigation, results for all physical measurement data (BMI, waist circumference and blood pressure) from 2014-15 are of suitable quality and are directly comparable to 2011-13 and earlier years.
Comparability with 2011-12