Codes and Frequencies
For sample adults whose biological father ever had colorectal cancer (BFCLRCAN), BFACLRCAN reports whether the respondent's biological father was under 50 years of age when first diagnosed with colorectal cancer.
In 2015, due to low frequencies among family members, cancers of the colon and rectum were removed from the NHIS public use file to maintain respondent confidentiality. To maintain continuity of data analyses using these cancers the "colorectal cancer" variable was created. Researchers may choose to recode the component cancers variables (BFACLCAN and BFARTCAN in 2000, 2005 and 2010 to mimic the "colorectal cancer" variables in 2015.
BFACLRCAN is one of a series of related variables in the "Family History" section of the Cancer Modules. 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).
- 2015: Sample adults whose biological father ever had colorectal cancer.
- 2015 : SAMPWEIGHT