A smartphone-based fecal immunochemical test (FIT) was found to be a reliable and accessible tool for colorectal cancer (CRC) screening, according to the results of a new population-based study published in Clinical Gastroenterology and Hepatology. The mobile app–enabled FIT achieved diagnostic performance comparable to laboratory-based FITs while significantly improving patient convenience and participation.
"In this first study to evaluate the utilization and performance of a digital smartphone-based test for early detection of CRC at home, more than one-half of the participants made use of the test, with higher rates among male participants and the most important target group under age 60 years," reported Michael Hoffmeister, PhD, of the German Cancer Research Center in Heidelberg, and colleagues.
The researchers enrolled 654 patients who were scheduled for screening colonoscopy across gastroenterology practices in southern Germany between 2021 and 2023. Participants were offered both a smartphone-based FIT (SmarTest FIT) and a laboratory-based FIT (FOB Gold). Fifty-five percent of participants used the smartphone-based FIT, while 98% used the laboratory FIT. Of those who used the smartphone test, 76% had valid results. Overall, 89% of participants found the smartphone-based FIT a useful alternative to the standard test.
Of the 361 participants using the smartphone-based FIT, 24% (87 people) had a failed test—meaning they began the process but did not submit a result. Among those with failed tests, 32% did not own a smartphone, and 51% encountered issues during testing—most often believing they had completed it (34%).
The sensitivity for detecting advanced neoplasms was 28% for the smartphone-based FIT vs 34% for the laboratory FIT, with identical specificity at 92%. Receiver operating characteristic analysis showed nearly equivalent—though not statistically significant—diagnostic accuracy, which suggested that the smartphone-based approach performs on par with standard FITs under real-world conditions.
The smartphone-based FIT uses a rapid immunochemical test cassette that is analyzed through a smartphone app and quantifies hemoglobin concentration in stool via color intensity. Users collect a stool sample, apply it to the cassette, and scan the test after 15 minutes using their phone’s camera, reported Hoffmeister and colleagues.
A feasibility questionnaire revealed overwhelmingly positive patient feedback. Of the participants, 92% agreed the app offered clear guidance, 94% found stool handling manageable, 89% felt test duration was appropriate, and 78% supported immediate result display within the app. Common barriers among nonusers included technical issues (47%), such as app or smartphone compatibility, and general skepticism toward digital testing (44%).
The findings point to a new tool for enhancing participation in CRC screening programs—particularly among younger, tech-savvy patients under 60 years who demonstrated higher adoption rates. Although colonoscopy remains the diagnostic gold standard, smartphone-based FITs could bridge gaps in accessibility by enabling at-home testing and digital result transmission. A positive test result, however, must still be followed by colonoscopy and physician consultation, the authors emphasized.
Integrating digital self-tests could help increase participation rates in colorectal cancer screening overall, provided quality controls are maintained. Further research may focus on long-term adherence, impact on CRC detection rates, and cost-effectiveness within organized screening programs.
The researchers disclosed no conflicts of interest.
Source: Clinical Gastroenterology and Hepatology
