Component Description
The ACASI section on sexual behavior (SXQ) provides information on lifetime and current sexual behavior for both men and women. Major items in this section include age at first sexual intercourse, number of sexual partners, sexual orientation, circumcision status (men) and history of sexually transmitted diseases.
Eligible Sample
Survey participants aged 14-69 years were eligible. Several questions in this section are age and gender specific. Mentally impaired individuals, or participants who were unable to understand English or Spanish, were not asked these questions. Only data from participants aged 20-69 years are included in this release. Special use data files for participants 14-19 years are available through the NCHS Research Data Center.
Interview Setting and Mode of Administration
The sexual behavior questionnaire was administered to survey participants 14-69 years old, during the physical examination at the examination center, in a private room, using the Audio Computer Assisted Self Interview (ACASI) system. The ACASI was conducted in either English or Spanish. The ACASI enables respondents to hear questions through earphones as well as read questions on the computer screen. Respondents move at their own speed and touch the screen to indicate their response. No proxy respondents or translators were used in situations when the respondents could not self-report.
Quality Assurance & Quality Control
For details on the QA/QC process for this component, please refer to the MEC Interview Manual on the NHANES website.
Data Processing and Editing
Responses to SXD031 (age at first sexual intercourse) that were 9 years or less were grouped and coded as “9 years or younger.”
Responses to SXD171 (# of female partners) that were 2000 or more partners were grouped and coded as “2000 or more” partners.
Analytic Notes
Compared to past NHANES cycles, the prevalence has gone up for respondents answering “No” to ever having sex, including respondents who were pregnant at exam, gave a history of pregnancy or self-reported being married, divorced, widowed, separated, or living with a partner. Analysts are advised to recode SXQ021 based on pregnancy status, ever been pregnant and marital status. Data will be missing for most of the variables in the sexual behavior section for these respondents, since an answer of “No” to SXQ021 skips the respondent out of the questionnaire, with an exception of one other question for females and two other questions for males.
Although this issue is more pronounced in the 2005-2006 and 2007-2008 data releases, this was also an issue in previous releases. If analysts are planning to combine data with previous cycles, they may want to consider the same type of recode for SXQ020.
Questions were slightly modified in the second year of collection. Questions originally specified three types of sex; vaginal, anal and oral. This proved to be confusing for respondents, particularly males who may have thought they had to have had all three types of sex in order to answer yes. These qualifiers were removed so that questions asked about “sex” but did not specify which types.
Analyst should keep in mind that the NHANES policy is that if a person wasn't asked a question it should be missing. If is up to the analyst to recode to zero if that is what they want to do. For example, if a respondent reported that they had zero lifetime sex partners, they wouldn't be asked the number of sex partners in the past 12 months. Since the respondent does not receive the question about partners in the past 12 months, the data will be coded as missing for this variable. Analyst may want to recode this to “0”.
Users are cautioned about the use of SXQ292 and SXQ294 in analyses, especially in analyses that classify respondents by their responses to these questions to describe or compare subgroup characteristics. The sample size for the non-heterosexual subgroups is limited and do not meet the minimum sample size requirements for statistical reliability as noted in the NHANES analytic guidelines1. Even after combining multiple years of data, which is often recommended to estimate rarer conditions within a subgroup, the non-heterosexual subgroups do not meet the minimum sample size. Additionally, there is a high rate of not selecting a specific answer to the questions. That is, selecting ‘don’t know’, ‘refused’, ‘not sure’ or ‘something else’ as a response. This issue has been examined at length at the NCHS Questionnaire Design Research Laboratory (QDRL) recently. Individuals select these answers for a variety of reasons that are well summarized in the report Design, Development and Testing of the NHIS Sexual Identity Question2, specifically in Table 2. For example, respondents from the LGBT community select “something else’ when they use a different sexual identity label than those presented in the response options. However, those who aren’t part of the LGBT community select this answer because they are not familiar with what the response options mean.
Exam sample weights should be used for analyses. Please refer to the Analytic Guidelines for further details on the use of sample weights and other analytic issues on the NHANES website. The Analytic Guidelines are available on the NHANES website.