The NHANES program suspended field operations in March 2020 due to the coronavirus disease 2019 (COVID-19) pandemic. As a result, data collection for the NHANES 2019-2020 cycle was not completed and the collected data are not nationally representative. Therefore, data collected from 2019 to March 2020 were combined with data from the NHANES 2017-2018 cycle to form a nationally representative sample of NHANES 2017-March 2020 pre-pandemic data. These data are available to the public. Please refer to the Analytic Notes section for more details on the use of the data.
The dermatology questionnaire (variable name prefix DEQ) section provides personal interview data on sun exposure and sun protective behavior.
All participants aged 20-59 years in the NHANES 2017-March 2020 pre-pandemic sample were eligible.
The DEQ was asked, in the home, by trained interviewers using the Computer-Assisted Personal Interview (CAPI) system.
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. The NHANES 2017-2018 and 2019-2020 questionnaires are available on the NHANES website.
Frequency counts were verified during the preparation of the file.
The COVID-19 pandemic required suspension of NHANES 2019-2020 field operations in March 2020 after data were collected in 18 of the 30 survey locations in the 2019-2020 sample. Because the collected data from 18 locations were not nationally representative, these data were combined with data from the previous cycle (2017-2018) to create a 2017-March 2020 pre-pandemic data file. The resulting sample weights in the demographic file should be used to calculate estimates from the combined cycles. These sample weights are not appropriate for independent analyses of the 2019-2020 data and will not yield nationally representative results for either the 2017-2018 data alone or the 2019-March 2020 data alone. Please refer to the NHANES website for additional information for the NHANES 2017-March 2020 pre-pandemic data, and for the previous 2017-2018 public use data file with specific weights for that 2-year cycle.
Responses to questions on time spent outside on work or school days (DEQ120) and on days not at work or at school (DEQ125) were collected in either hours or minutes. For data release purposes, all responses were converted to minutes. If participants indicated that they did not spend any time outdoors, then their values for these questions were set to zero. The corresponding description in the codebook is “no time spent outdoors”. Values of 1-14 minutes were grouped into one category. The code “3333” was set for participants who reported “does not work or go to school” to DEQ120 or “at work or at school 9 to 5 seven days a week” to DEQ125. These variables were then renamed DED120 and DED125 for release, respectively.
Responses to question DEQ038Q, “How many times in the past year have you had a sunburn?” with values of 20 or more were combined into one category and labeled “20”.
Analysts should be aware that some questions may have very few responses. Even with two years of data collection, there may not be sufficient sample size for such variables to be analytically useful. In these cases, it may be necessary to combine more than two years of data to conduct analysis.
Although dermatology data were collected as part of the household questionnaire, if they are merged with the MEC exam data, exam sample weights should be used for the 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.
| Code or Value | Value Description | Count | Cumulative | Skip to Item |
|---|---|---|---|---|
| 1 | Always | 503 | 503 | |
| 2 | Most of the time | 1531 | 2034 | |
| 3 | Sometimes | 2509 | 4543 | |
| 4 | Rarely, or | 907 | 5450 | |
| 5 | Never? | 331 | 5781 | |
| 6 | Don't go out in the sun | 24 | 5805 | DED120 |
| 77 | Refused | 0 | 5805 | |
| 99 | Don't know | 3 | 5808 | |
| . | Missing | 2 | 5810 |
| Code or Value | Value Description | Count | Cumulative | Skip to Item |
|---|---|---|---|---|
| 1 | Always | 312 | 312 | |
| 2 | Most of the time | 501 | 813 | |
| 3 | Sometimes | 1603 | 2416 | |
| 4 | Rarely, or | 1446 | 3862 | |
| 5 | Never? | 1919 | 5781 | |
| 7 | Refused | 0 | 5781 | |
| 9 | Don't know | 3 | 5784 | |
| . | Missing | 26 | 5810 |
| Code or Value | Value Description | Count | Cumulative | Skip to Item |
|---|---|---|---|---|
| 1 | Always | 481 | 481 | |
| 2 | Most of the time | 701 | 1182 | |
| 3 | Sometimes | 1194 | 2376 | |
| 4 | Rarely, or | 1061 | 3437 | |
| 5 | Never? | 2347 | 5784 | |
| 7 | Refused | 0 | 5784 | |
| 9 | Don't know | 0 | 5784 | |
| . | Missing | 26 | 5810 |
| Code or Value | Value Description | Count | Cumulative | Skip to Item |
|---|---|---|---|---|
| 15 to 480 | Range of Values | 3946 | 3946 | |
| 0 | No time spent outdoors | 1107 | 5053 | |
| 14 | 1-14 minutes | 183 | 5236 | |
| 3333 | Does not work or go to school | 552 | 5788 | |
| 7777 | Refused | 1 | 5789 | |
| 9999 | Don't Know | 15 | 5804 | |
| . | Missing | 6 | 5810 |
| Code or Value | Value Description | Count | Cumulative | Skip to Item |
|---|---|---|---|---|
| 15 to 480 | Range of Values | 5005 | 5005 | |
| 0 | No time spent outdoors | 672 | 5677 | |
| 14 | 1-14 minutes | 87 | 5764 | |
| 3333 | At work or at school 9 to 5 seven days a week | 10 | 5774 | |
| 7777 | Refused | 3 | 5777 | |
| 9999 | Don't Know | 27 | 5804 | |
| . | Missing | 6 | 5810 |