BSTOLNO is a 2-digit-numeric variable.
0: Not in universe
98: Unknown-not ascertained
99: Unknown-don't know
For sample adults over age 40 who ever had an office blood stool test and reported the time since their most recent blood stool in a number and time period format (e.g., 30 days), BSTOLNO reports the number of units (e.g., 30) since the most recent office blood stool test.
In 2015, the wording of the question asking whether respondents had ever had a blood stool test during an office visit (BSTOEV) changed slightly to more inclusive language. Prior to 2015, respondents were asked whether they ever had "a blood stool test" in which a doctor or other health care professional collected a stool sample during an office visit. Beginning in 2015, the language was expanded to "a blood stool or FIT test".
- 2000; 2005; 2010; 2015: Sample adults age 40+ who ever had office blood stool test and answered in number and time period format.
- 2000, 2005, 2010, 2015
- 2000, 2005, 2010, 2015 : SAMPWEIGHT