Table of Contents

Component Description

The NHANES 2013-14 preventive aspirin use questionnaire (RXQASA_H) provides data on low-dose aspirin taken to prevent heart attacks, strokes, and cancer. It is a continuous NHANES data collection specifically designed to estimate the prevalence of low-dose, over the counter preventive aspirin use in the United States. Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in the U.S. and taking low dose aspirin is demonstrated to be beneficial for the secondary prevention of CVD (AHA, 2009; USPSTF, 2009). Increasing aspirin use among those persons who are at high risk for CVD is a key U.S. Public Health objective (Frieden & Berwick, 2011).

RXQASA_H data collection topics include:

  • Whether a doctor recommended low dose aspirin for preventive use.
  • Adherence to this medical advice; and whether aspirin was stopped due to side effects.
  • Whether the low-dose aspirin was taken on one’s own initiative.
  • The schedule and frequency of aspirin use.
  • The specific aspirin dose taken.

The RXQASA_H data collection format was designed to provide both current and lifetime prevalence estimates of preventive aspirin use: overall use; doctor recommended use; and self-initiated use. When combined with other 2013-14 NHANES data, the prevalence of low-dose aspirin use for both primary and secondary prevention can be estimated, as well as the prevalence of aspirin use in key U.S. population subgroups: those with coronary artery disease, angina, heart attack, stroke, and diabetes. Also, preventive aspirin use prevalence can be monitored across the major demographic subgroups, such as age, gender, and race/ethnicity. Person-level population-based estimates of the distributions of aspirin doses taken and of scheduled frequency of use are also supported.

Eligible Sample

All survey participants 40 years of age and older were eligible.

Interview Setting and Mode of Administration

The preventive aspirin use questions were asked, in the home, by trained interviewers using the Computer-Assisted Personal Interview (CAPI) system. They were administrated as part of Dietary Supplements and Prescription Medication (DSQ) section of the Sample Person (SP) Questionnaire, which collects information on dietary supplements, nonprescription antacids and prescription medication. The Interviewer Procedure Manuals and Survey Questionnaires can be found on the NHANES website https://wwwn.cdc.gov/nchs/data/nhanes/2013-2014/questionnaires/dsq_h.pdf.

Quality Assurance & Quality Control

The CAPI system is programmed with built-in consistency checks to reduce data entry errors. CAPI also uses online help screens to assist interviewers in defining key terms used in the questionnaire.

Data Processing and Editing

Frequency counts were checked, “skip” patterns were verified, and the reasonableness of question responses was reviewed. Edits were made to some variables to ensure the completeness, consistency, and analytic usefulness of the data.

The Preventive Aspirin Use questionnaire captured data on the actual dose of aspirin taken by the participant (RXD530). While most survey participants were taking 81mg aspirin, the data for this variable was not grouped or edited, so as to provide data analysts with the actual doses of aspirin reported by the survey participants. These aspirin doses ranged from 20mg to 500mg.

Analytic Notes

The 2013-14 preventive aspirin use data file (RXQASA_H) is similar to the 2011-12 publicly release data file. It is formatted as person-level data, where each participant has only one record. The low-dose aspirin reported in this data file is usually available over-the-counter without prescription. However, some state laws might require prescriptions for such over-the-counter medications. Also, sometimes physicians might write prescriptions for preventive aspirin. The RXQASA_H data for the most part represents the non-prescription over-the-counter aspirin use; however, the few instances where prescription aspirin was used for preventive purposes are also included in this data file.

Other prior NHANES data collections on over-the-counter and prescription aspirin use dose information was not captured so it is not possible to distinguish low-dose preventive aspirin use from analgesic aspirin use. The context of these previous aspirin use data collections was to assess the role of aspirin therapy in arthritis and musculoskeletal pain: NHANES I (1971-75), NHANES II (1976-80), NHANES 2009-10; and to perform surveys focused on general analgesic use prevalence: NHANES III (1988-94) and NHANES 1999-2004.

The analysis of NHANES 2013–14 aspirin use questionnaire data must be conducted using the appropriate survey design variables, sample weights, and the basic demographic variables. Interview weights should only be used if questionnaire data are analyzed by themselves. However if RXQASA_H data are merged with the MEC examination data or laboratory data, the MEC examination weights should be used for analyses. If RXQASA_H data are merged with laboratory sub-sample data, sub-sample weights should be used for analyses.

Please refer to the NHANES Analytic Guidelines and the on-line NHANES Tutorial for further details on the use of sample weights and other analytic issues.

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 40 YEARS - 150 YEARS

RXQ510 - Dr told to take daily low-dose aspirin?

Variable Name:
RXQ510
SAS Label:
Dr told to take daily low-dose aspirin?
English Text:
Doctors and other health care providers sometimes recommend that {you take/SP takes) a low-dose aspirin each day to prevent heart attacks, strokes, or cancer. {Have you/Has SP} ever been told to do this?
English Instructions:
INTERVIEWER INSTRUCTION: IF THE RESPONDENT VOLUNTEERS THEY HAVE BEEN TOLD TO TAKE AN ASPIRIN EVERY OTHER DAY OR 'REGULARLY' FOR THESE REASONS, CODE "YES".
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 1284 1284
2 No 2524 3808 RXQ520
7 Refused 3 3811 RXQ520
9 Don't know 4 3815 RXQ520
. Missing 0 3815

RXQ515 - Followed advice, took low-dose aspirin?

Variable Name:
RXQ515
SAS Label:
Followed advice, took low-dose aspirin?
English Text:
{Are you/Is SP} now following this advice?
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 946 946 RXQ525G
2 No 229 1175 End of Section
3 Sometimes 60 1235 RXQ525G
4 Stopped aspirin use due to side effects 49 1284 End of Section
. Missing 2531 3815

RXQ520 - Taking low-dose aspirin on your own?

Variable Name:
RXQ520
SAS Label:
Taking low-dose aspirin on your own?
English Text:
On {your/SP's} own, {are you/is SP} now taking a low-dose aspirin each day to prevent heart attacks, strokes, or cancer?
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 133 133
2 No 2392 2525 End of Section
7 Refused 3 2528 End of Section
9 Don't know 3 2531 End of Section
. Missing 1284 3815

RXQ525G - Schedule/frequency of aspirin use

Variable Name:
RXQ525G
SAS Label:
Schedule/frequency of aspirin use
English Text:
How often {do you/does SP} take an aspirin? (ASA taken daily, on alternate days, or another schedule?)
English Instructions:
CAPI INSTRUCTION: Soft edit: if > 2 per day.
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 One every day 969 969 RXD530
2 One every other day 67 1036 RXD530
3 Another schedule 96 1132
7 Refused 0 1132 RXD530
9 Don't know 1 1133 RXD530
. Missing 2682 3815

RXQ525Q - Another ASA schedule: number of doses

Variable Name:
RXQ525Q
SAS Label:
Another ASA schedule: number of doses
English Text:
How often {do you/does SP} take an aspirin? (Number of ASA doses taken per day or per week).
English Instructions:
ENTER NUMBER CAPI INSTRUCTION: Soft edit: if > 2 per day.
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 to 999 Range of Values 96 96
. Missing 3719 3815

RXQ525U - Another ASA schedule: frequency of doses

Variable Name:
RXQ525U
SAS Label:
Another ASA schedule: frequency of doses
English Text:
How often {do you/does SP} take an aspirin? (ASA doses taken on daily or weekly basis?)
English Instructions:
ENTER UNIT CAPI INSTRUCTION: Soft edit: if >2 per day.
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Per day 12 12
2 Per week 83 95
. Missing 3720 3815

RXD530 - Aspirin dose in milligrams (mg)

Variable Name:
RXD530
SAS Label:
Aspirin dose in milligrams (mg)
English Text:
What is the size or dose that {you take/SP takes}?
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
20 to 500 Range of Values 1121 1121
77777 Refused 0 1121
99999 Don't know 12 1133
. Missing 2682 3815