Table of Contents

Component Description

Accurate measurement of blood pressure (BP) is a major public health concern; it is essential for hypertension screening, as well as for disease management. Hypertension is a powerful, consistent and independent risk factor for cardiovascular disease and renal disease.

Eligible Sample

Heart rate is measured on all children 0-7 years of age; radial pulse is measured on examinees 8 years and older; and blood pressure (BP) is measured on all examinees 8 years and older.

Exclusion criteria: presence of the following on both arms: rashes, gauze dressings, casts, edema, paralysis, tubes, open sores or wounds, withered arms, a-v shunts, or if blood has been drawn from arm within the last week.

Protocol and Procedure

After resting quietly in a sitting position for 5 minutes and determining the maximum inflation level (MIL), three consecutive blood pressure readings are obtained. If a blood pressure measurement is interrupted or incomplete, a fourth attempt may be made. All BP determinations (systolic and diastolic) are taken in the Mobile Examination Center (MEC).

Quality Assurance & Quality Control

The BP examiners are certified for blood pressure measurement through a training program from Shared Care Research and Education Consulting. Certification is achieved when physician examiners meet all requirements of the training program. The initial training includes:

  • didactic instruction about BP measurement and propensity for error;
  • practice listening to systolic and diastolic BP sounds using a standardized audio-video tape presentation;
  • audio-video tape test;
  • written exam;
  • examiner and gold standard instructor simultaneously listening to BP of a minimum of 20 volunteers of all ages through a Y- stethoscope to compare measures; and
  • observation of protocol technique using a checklist.

Certification requires a score of 100 per cent on the audio-video tape test. Correct answers on the audio-video tape test require the examiner’s answers and the standardized test answers to be within +/- 2mm mercury (Hg) on 92 per cent of 24 measures (12 systolic, 12 diastolic), and within +/- 4mm Hg on 100 percent of 24 measures (12 systolic, 12 diastolic). For more information on quality assurance and control, see Ostchega et al. (Ostchega, 2003).

For more details on the QA/QC process for this component, please refer to the Physician Section of the MEC Operations Manual. 

Data Processing and Editing

The following specifications were programmed in the computer system used to capture the blood pressure data:

  • systolic blood pressure and maximum inflation level cannot be greater than 300 mmHg;
  • systolic and diastolic blood pressure and maximum inflation level can be even numbers only;
  • systolic blood pressure must be greater than diastolic blood pressure;
  • if there is no systolic blood pressure, there can be no diastolic blood pressure;
  • diastolic blood pressure can be zero

Analytic Notes

Please refer to the Analytic Guidelines for further details on the use of sample weights and other analytic issues. The Analytic Guidelines are available on the NHANES website.

References

Codebook and Frequencies

SEQN - Respondent sequence number

Variable Name:
SEQN
SAS Label:
Respondent sequence number
English Text:
Respondent sequence number.
Target:
Both males and females 0 YEARS - 150 YEARS

PEASCST1 - Blood Pressure Status

Variable Name:
PEASCST1
SAS Label:
Blood Pressure Status
English Text:
Blood Pressure Status
Target:
Both males and females 0 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Complete 9512 9512
2 Partial 101 9613
3 Not done 337 9950
. Missing 0 9950

PEASCTM1 - Blood Pressure Time in Seconds

Variable Name:
PEASCTM1
SAS Label:
Blood Pressure Time in Seconds
English Text:
Blood Pressure Time in Seconds
Target:
Both males and females 0 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
2 to 2679 Range of Values 9641 9641
. Missing 309 9950

PEASCCT1 - Blood Pressure Comment

Variable Name:
PEASCCT1
SAS Label:
Blood Pressure Comment
English Text:
Blood Pressure Comment
Target:
Both males and females 0 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Safety exclusion 4 4
2 SP refusal 104 108
3 No time 2 110
4 Physical limitation 34 144
5 Communication problem 5 149
7 SP ill/emergency 10 159
14 Interrupted 2 161
56 Came late/left early 142 303
84 SP with child 3 306
99 Other, specify 132 438
. Missing 9512 9950

BPXCHR - 60 sec HR (30 sec HR * 2)

Variable Name:
BPXCHR
SAS Label:
60 sec HR (30 sec HR * 2)
English Text:
60 sec HR (30 sec HR * 2)
Target:
Both males and females 0 YEARS - 7 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 288 Range of Values 2168 2168
. Missing 7782 9950

BPQ150A - Had food in the past 30 minutes?

Variable Name:
BPQ150A
SAS Label:
Had food in the past 30 minutes?
English Text:
Have you had any of the following in the past 30 minutes?: Food
English Instructions:
Check each that applies
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 2167 2167
2 No 5288 7455
. Missing 2495 9950

BPQ150B - Had alcohol in the past 30 minutes?

Variable Name:
BPQ150B
SAS Label:
Had alcohol in the past 30 minutes?
English Text:
Have you had any of the following in the past 30 minutes?: Alcohol
English Instructions:
Check each that applies
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 4 4
2 No 7451 7455
. Missing 2495 9950

BPQ150C - Had coffee in the past 30 minutes?

Variable Name:
BPQ150C
SAS Label:
Had coffee in the past 30 minutes?
English Text:
Have you had any of the following in the past 30 minutes?: Coffee
English Instructions:
Check each that applies
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 27 27
2 No 7428 7455
. Missing 2495 9950

BPQ150D - Had cigarettes in the past 30 minutes?

Variable Name:
BPQ150D
SAS Label:
Had cigarettes in the past 30 minutes?
English Text:
Have you had any of the following in the past 30 minutes?: Cigarettes
English Instructions:
Check each that applies
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 90 90
2 No 7365 7455
. Missing 2495 9950

BPAARM - Arm selected:

Variable Name:
BPAARM
SAS Label:
Arm selected:
English Text:
Arm selected:
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Right 7356 7356
2 Left 37 7393
8 Could not obtain 62 7455
. Missing 2495 9950

BPACSZ - Coded cuff size

Variable Name:
BPACSZ
SAS Label:
Coded cuff size
English Text:
Cuff size (cm) (width X length)
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Infant (6X12) 1 1
2 Child (9X17) 457 458
3 Adult (12X22) 2793 3251
4 Large (15X32) 3291 6542
5 Thigh (18X35) 846 7388
. Missing 2562 9950

BPXPLS - 60 sec. pulse (30 sec. pulse * 2):

Variable Name:
BPXPLS
SAS Label:
60 sec. pulse (30 sec. pulse * 2):
English Text:
60 sec. pulse (30 sec. pulse * 2):
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
40 to 220 Range of Values 7441 7441
. Missing 2509 9950

BPXDB - # of dropped beats in 30 seconds

Variable Name:
BPXDB
SAS Label:
# of dropped beats in 30 seconds
English Text:
# of dropped beats in 30 seconds
Target:
Both males and females 12 YEARS - 49 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 to 18 Range of Values 55 55
. Missing 9895 9950

BPXPULS - Pulse regular or irregular?

Variable Name:
BPXPULS
SAS Label:
Pulse regular or irregular?
English Text:
Pulse regular or irregular?
Target:
Both males and females 0 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Regular 9230 9230
2 Irregular 208 9438
. Missing 512 9950

BPXPTY - Pulse type:

Variable Name:
BPXPTY
SAS Label:
Pulse type:
English Text:
Pulse type:
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Radial 7444 7444
2 Brachial 5 7449
8 Could not obtain 0 7449
. Missing 2501 9950

BPXML1 - MIL: maximum inflation levels (mm Hg)

Variable Name:
BPXML1
SAS Label:
MIL: maximum inflation levels (mm Hg)
English Text:
MIL: maximum inflation levels (mm Hg)
Target:
Both males and females 8 YEARS - 150 YEARS
Hard Edits:
70.0000 to 300.0000
Code or Value Value Description Count Cumulative Skip to Item
110 to 290 Range of Values 7377 7377
888 Could not obtain 0 7377
. Missing 2573 9950

BPXSY1 - Systolic: Blood pres (1st rdg) mm Hg

Variable Name:
BPXSY1
SAS Label:
Systolic: Blood pres (1st rdg) mm Hg
English Text:
Systolic: Blood pressure (first reading) mm Hg
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
74 to 270 Range of Values 6668 6668
. Missing 3282 9950

BPXDI1 - Diastolic: Blood pres (1st rdg) mm Hg

Variable Name:
BPXDI1
SAS Label:
Diastolic: Blood pres (1st rdg) mm Hg
English Text:
Diastolic: Blood pressure (first reading) mm Hg
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 124 Range of Values 6668 6668
. Missing 3282 9950

BPAEN1 - Enhancement used first reading

Variable Name:
BPAEN1
SAS Label:
Enhancement used first reading
English Text:
Enhancement used first reading
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 0 0
2 No 7388 7388
8 Could not obtain 0 7388
. Missing 2562 9950

BPXSY2 - Systolic: Blood pres (2nd rdg) mm Hg

Variable Name:
BPXSY2
SAS Label:
Systolic: Blood pres (2nd rdg) mm Hg
English Text:
Systolic: Blood pressure (second reading) mm Hg
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
72 to 232 Range of Values 6265 6265
. Missing 3685 9950

BPXDI2 - Diastolic: Blood pres (2nd rdg) mm Hg

Variable Name:
BPXDI2
SAS Label:
Diastolic: Blood pres (2nd rdg) mm Hg
English Text:
Diastolic: Blood pressure (second reading) mm Hg
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 124 Range of Values 6265 6265
. Missing 3685 9950

BPAEN2 - Enhancement used second reading

Variable Name:
BPAEN2
SAS Label:
Enhancement used second reading
English Text:
Enhancement used second reading
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 138 138
2 No 7246 7384
8 Could not obtain 0 7384
. Missing 2566 9950

BPXSY3 - Systolic: Blood pres (3rd rdg) mm Hg

Variable Name:
BPXSY3
SAS Label:
Systolic: Blood pres (3rd rdg) mm Hg
English Text:
Systolic: Blood pressure (third reading) mm Hg
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
78 to 234 Range of Values 6091 6091
. Missing 3859 9950

BPXDI3 - Diastolic: Blood pres (3rd rdg) mm Hg

Variable Name:
BPXDI3
SAS Label:
Diastolic: Blood pres (3rd rdg) mm Hg
English Text:
Diastolic: Blood pressure (third reading) mm Hg
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 122 Range of Values 6091 6091
. Missing 3859 9950

BPAEN3 - Enhancement used third reading

Variable Name:
BPAEN3
SAS Label:
Enhancement used third reading
English Text:
Enhancement used third reading
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 137 137
2 No 7247 7384
8 Could not obtain 0 7384
. Missing 2566 9950

BPXSY4 - Systolic: Blood pres (4th rdg) mm Hg

Variable Name:
BPXSY4
SAS Label:
Systolic: Blood pres (4th rdg) mm Hg
English Text:
Systolic: Blood pressure (fourth reading if necessary) mm Hg
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
76 to 222 Range of Values 1179 1179
. Missing 8771 9950

BPXDI4 - Diastolic: Blood pres (4th rdg) mm Hg

Variable Name:
BPXDI4
SAS Label:
Diastolic: Blood pres (4th rdg) mm Hg
English Text:
Diastolic: Blood pressure (fourth reading if necessary) mm Hg
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 124 Range of Values 1179 1179
. Missing 8771 9950

BPAEN4 - Enhancement used fourth reading

Variable Name:
BPAEN4
SAS Label:
Enhancement used fourth reading
English Text:
Enhancement used fourth reading
Target:
Both males and females 8 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 112 112
2 No 2086 2198
8 Could not obtain 0 2198
. Missing 7752 9950