Fecal immunochemical test (FIT) versus colonoscopy: Does knowing that a positive FIT requires a follow-up colonoscopy affect initial decision making in the US?

Although many people prefer fecal immunochemical test (FIT) over colonoscopy due to its noninvasive nature, it is unclear whether FIT would still be preferred for colorectal cancer (CRC) screening if they were explicitly informed that + FIT requires follow-up colonoscopy. To address this gap, we administered two conjoint analysis surveys-one that explained the need for a follow-up colonoscopy after + FIT while the other did not-to a US nationwide sample of Americans and then assessed whether there were differences in colonoscopy/FIT preferences between cohorts. We recruited adults ≥ 40yo who had not undergone CRC screening via an online survey research firm. We deployed two surveys that used conjoint analysis to assess decision making surrounding CRC screening tests: Survey 1 (4/2-4/15/2021)-did not inform participants that they need a colonoscopy following a + FIT; Survey 2 (4/29-6/2/2021)-informed respondents of the potential need. Using the conjoint analysis data, we determined the proportion of those who preferred FIT or colonoscopy and then used logistic regression to assess for differences in colonoscopy/FIT preferences between the cohorts. Overall, 501 and 1,000 individuals completed Survey 1 (without description of need for colonoscopy after + FIT) and Survey 2 (with description), respectively. There was no difference in test preference between cohorts after adjusting for covariates in the logistic regression (adjusted p = 0.09): Survey 1 (without description)-colonoscopy 28.5%, FIT 71.5%; Survey 2 (with description)-colonoscopy 26.7%, FIT 73.3%. Thus, knowledge that a + FIT requires a follow-up colonoscopy does not alter people's strong preference for non-invasive stool testing with FIT.