BDNESCAN is a two-digit count variable.
00: Not in Universe
21: Top code of 21 or more
98: Unknown-Not Ascertained
99: Unknown-Don't Know
For sample adults with at least one biological daughter (BDNUM) who ever had esophagus cancer (BDESCAN), BDNESCAN reports the number of biological daughters who had ever been told they had esophagus cancer. Only respondents with at least one biological daughter (BDNUM) who ever had cancer of any kind (BDNHCAN) were asked follow-up questions about what kind(s) of cancer their daughter(s) had, and about the number of biological daughters they had with the specified type(s) of cancer (such as esophagus cancer).
Beginning in 2015, details about esophagus cancer (and several other cancer types) were suppressed because of low frequencies of these types of cancer among family members. Cancers of the esophagus, larynx-windpipe, mouth/tongue/lip, and throat-pharynx are not available separately on the NHIS public use files to protect confidentiality; incidence of these cancer types among biological daughters are all combined in BDNHNCAN, which reports the number of biological daughters ever diagnosed with head and neck cancer.
BDNESCAN is one of a series of related variables in the "Family History" section of the 2000, 2005, and 2010 Cancer Modules. In all three years, this section begins with the general comment:
According to the 2000 and 2005 Field Representative's Manuals, the purpose of this and other family cancer history questions is to "determine the prevalence of cancer in families in the population" to "allow a greater understanding of how data obtained from genetics clinics can be applied to the general population." The 2010 Manual provides a similar rationale, stating that the collection of this data "will allow analysts a greater understanding of how family history relates to cancer."
The Manuals for all three years define "biological" relatives as people related by blood. Thus, a respondent's biological daughter is a daughter related to the respondent by blood (i.e., not a stepdaughter, adopted daughter, foster daughter, or daughter-in-law).
BDNESCAN is fully comparable between 2005 and 2010.
BDNESCAN is largely comparable between 2000 and 2005/2010. In 2000, persons who answered less than 50 percent of the questions in the supplement had a value of "not ascertained" automatically inserted in the appropriate fields of the Cancer Control Module file, whereas in 2005 and later years, persons who answered none of the questions in the supplement had a value of "not ascertained" automatically inserted in the appropriate fields of the Cancer Control Module file.
- 2000; 2005; 2010: Sample adults age 18+ whose daughter(s) ever had esophageal cancer.
- 2000, 2005, 2010
- 2000, 2005, 2010 : SAMPWEIGHT