Codes and Frequencies
For sample adults whose biological father ever had cancer of any kind (BFHCAN), BFOCCAN reports whether the respondent's biological father ever had a kind of cancer not asked about in the survey question. Please see the Survey Text Tab for the survey question associated with this variable, which specifies the types of cancer included in the survey.
BFOCCAN is one of a series of related variables in the "Family History" section of the 2000 and later Cancer Modules. The same types of cancer were asked about in all years; however, beginning in 2015, certain types of cancer are suppressed because of low frequencies of those types of cancer among family members.
Suppressed cancer types in the 2015 data are not included in "other" cancer types. Family history variables related to cancers of the bladder, blood, bone, brain, gallbladder, liver, pancreas, and soft tissue (muscle or fat) are asked about in the survey, but are not included in the 2015 data.
Additionally, cancers of the esophagus, larynx-windpipe, mouth/tongue/lip, and throat-pharynx are not available separately, but are combined in a set of variables about head and neck cancer. Similarly, cancers of the colon and rectum are not available separately, but are combined in a set of variables about colorectal cancer.
In all 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 and later Manuals provide a similar rationale, stating that the collection of these data "will allow analysts a greater understanding of how family history relates to cancer."
The Manuals for all years define "biological" relatives as people related by blood. Thus, a respondent's biological father is a father related to the respondent by blood (i.e., not a stepfather, adoptive father, foster father, or father-in-law).
BFOCCAN is fully comparable between 2005 and later years.
BFOCCAN is largely comparable between 2000 and 2005 and later years, though there may be some difference in the meaning of "refused," "not ascertained," and "don't know" as used in 2000 compared to the meanings of those terms in 2005 and later years.
The Survey Descriptions for all years caution that while "all sample adults were to be asked the questions in the Cancer Control Module, some persons did not complete the supplement." 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; 2015: Sample adults aged 18 and older whose biological father ever diagnosed with cancer.
- 2000, 2005, 2010, 2015
- 2000, 2005, 2010, 2015 : SAMPWEIGHT