title: Risk factors for false positive and for false negative test results in screening with fecal occult blood testing.
abstract: Differences in the risk of a false negative or a false positive fecal immunochemical test (FIT) across subgroups may affect optimal screening strategies. We evaluate whether subgroups are at increased risk of a false positive or a false negative FIT result, whether such variability in risk is related to differences in FIT sensitivity and specificity or to differences in prior CRC risk. Randomly selected, asymptomatic individuals were invited to undergo colonoscopy. Participants were asked to undergo one sample FIT and to complete a risk questionnaire. We identified patient characteristics associated with a false negative and false positive FIT results using logistic regression. We focused on statistically significant differences as well as on variables influencing the false positive or negative risk for which the odds ratio exceeded 1.25. Of the 1,426 screening participants, 1,112 (78%) completed FIT and the questionnaire; 101 (9.1%) had advanced neoplasia. 102 Individuals were FIT positive, 65 (64%) had a false negative FIT result and 66 (65%) a false positive FIT result. Participants at higher age and smokers had a significantly higher risk of a false negative FIT result. Males were at increased risk of a false positive result, so were smokers and regular NSAID users. FIT sensitivity was lower in females. Specificity was lower for males, smokers and regular NSAID users. FIT sensitivity was lower in women. FIT specificity was lower in males, smokers and regular NSAID users. Our results can be used for further evidence based individualization of screening strategies.
authors: Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Academical Medical Center, Amsterdam, The Netherlands; Department of research and development, NDDO Institute for Prevention and Early Diagnostic, Amsterdam, The Netherlands.
authors: Inge
authors: I
authors: Stegeman
authors: Thomas R
authors: TR
authors: de Wijkerslooth
authors: Esther M
authors: EM
authors: Stoop
authors: Monique
authors: M
authors: van Leerdam
authors: M
authors: M
authors: van Ballegooijen
authors: Roderik A
authors: RA
authors: Kraaijenhagen
authors: Paul
authors: P
authors: Fockens
authors: Ernst J
authors: EJ
authors: Kuipers
authors: Evelien
authors: E
authors: Dekker
authors: Patrick M
authors: PM
authors: Bossuyt
mesh_terms: D019411:Clinical Laboratory Techniques / Q000379:methods / Q000592:standards*; D003113:Colonoscopy / Q000379:methods; D005188:False Negative Reactions; D005189:False Positive Reactions; D005243:Feces / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods / Q000592:standards; D008875:Middle Aged; D009780:Occult Blood; D010865:Pilot Projects; D012306:Risk; D012307:Risk Factors; D012680:Sensitivity and Specificity
keywords: colorectal cancer; false negative; false positive; fecal immunochemical test; prevention; screening