title: Fecal Immunochemical Test (FIT) for Colon Cancer Screening: Variable Performance with Ambient Temperature.
abstract: Fecal immunochemical tests (FITs) are widely used in colorectal cancer (CRC) screening, but hemoglobin degradation, due to exposure of the collected sample to high temperatures, could reduce test sensitivity. We examined the relation of ambient temperature exposure with FIT positivity rate and sensitivity.
  
  
  
  This was a retrospective cohort study of patients 50 to 75 years in Kaiser Permanente Northern California's CRC screening program, which began mailing FIT kits annually to screen-eligible members in 2007. Primary outcomes were FIT positivity rate and sensitivity to detect CRC. Predictors were month, season, and daily ambient temperatures of test result dates based on US National Oceanic and Atmospheric Administration data.
  
  
  
  Patients (n = 472,542) completed 1,141,162 FITs. Weekly test positivity rate ranged from 2.6% to 8.0% (median, 4.4%) and varied significantly by month (June/July vs December/January rate ratio [RR] = 0.79, 95% confidence interval [CI], 0.76 to 0.83) and season. FIT sensitivity was lower in June/July (74.5%; 95% CI, 72.5 to 76.6) than January/December (78.9%; 95% CI, 77.0 to 80.7).
  
  
  
  FITs completed during high ambient temperatures had lower positivity rates and lower sensitivity. Changing kit design, specimen transportation practices, or avoiding periods of high ambient temperatures may help optimize FIT performance, but may also increase testing complexity and reduce patient adherence, requiring careful study.
authors.affiliation: From the University of Pennsylvania (CAD); Division of Research, Kaiser Permanente, Oakland, CA (CDJ, DAC, TRL); American Cancer Society, Atlanta, GA (SAF); Research and Evaluation, Kaiser Permanente, Pasadena, CA (VPQ, JES); Memorial Sloan Kettering Cancer Center, New York, NY (AGZ).
authors.forename: Chyke A
authors.initials: CA
authors.lastname: Doubeni
authors.affiliation: From the University of Pennsylvania (CAD); Division of Research, Kaiser Permanente, Oakland, CA (CDJ, DAC, TRL); American Cancer Society, Atlanta, GA (SAF); Research and Evaluation, Kaiser Permanente, Pasadena, CA (VPQ, JES); Memorial Sloan Kettering Cancer Center, New York, NY (AGZ).
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Jensen
authors.affiliation: From the University of Pennsylvania (CAD); Division of Research, Kaiser Permanente, Oakland, CA (CDJ, DAC, TRL); American Cancer Society, Atlanta, GA (SAF); Research and Evaluation, Kaiser Permanente, Pasadena, CA (VPQ, JES); Memorial Sloan Kettering Cancer Center, New York, NY (AGZ).
authors.forename: Stacey A
authors.initials: SA
authors.lastname: Fedewa
authors.affiliation: From the University of Pennsylvania (CAD); Division of Research, Kaiser Permanente, Oakland, CA (CDJ, DAC, TRL); American Cancer Society, Atlanta, GA (SAF); Research and Evaluation, Kaiser Permanente, Pasadena, CA (VPQ, JES); Memorial Sloan Kettering Cancer Center, New York, NY (AGZ).
authors.forename: Virginia P
authors.initials: VP
authors.lastname: Quinn
authors.affiliation: From the University of Pennsylvania (CAD); Division of Research, Kaiser Permanente, Oakland, CA (CDJ, DAC, TRL); American Cancer Society, Atlanta, GA (SAF); Research and Evaluation, Kaiser Permanente, Pasadena, CA (VPQ, JES); Memorial Sloan Kettering Cancer Center, New York, NY (AGZ).
authors.forename: Ann G
authors.initials: AG
authors.lastname: Zauber
authors.affiliation: From the University of Pennsylvania (CAD); Division of Research, Kaiser Permanente, Oakland, CA (CDJ, DAC, TRL); American Cancer Society, Atlanta, GA (SAF); Research and Evaluation, Kaiser Permanente, Pasadena, CA (VPQ, JES); Memorial Sloan Kettering Cancer Center, New York, NY (AGZ).
authors.forename: Joanne E
authors.initials: JE
authors.lastname: Schottinger
authors.affiliation: From the University of Pennsylvania (CAD); Division of Research, Kaiser Permanente, Oakland, CA (CDJ, DAC, TRL); American Cancer Society, Atlanta, GA (SAF); Research and Evaluation, Kaiser Permanente, Pasadena, CA (VPQ, JES); Memorial Sloan Kettering Cancer Center, New York, NY (AGZ).
authors.forename: Douglas A
authors.initials: DA
authors.lastname: Corley
authors.affiliation: From the University of Pennsylvania (CAD); Division of Research, Kaiser Permanente, Oakland, CA (CDJ, DAC, TRL); American Cancer Society, Atlanta, GA (SAF); Research and Evaluation, Kaiser Permanente, Pasadena, CA (VPQ, JES); Memorial Sloan Kettering Cancer Center, New York, NY (AGZ).
authors.forename: Theodore R
authors.initials: TR
authors.lastname: Levin
mesh_terms: D000368:Aged; D002140:California; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D055088:Early Detection of Cancer / Q000379:methods*; D005189:False Positive Reactions; D005260:Female; D006454:Hemoglobins / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D007159:Immunologic Tests; D008297:Male; D008875:Middle Aged; D009780:Occult Blood; D010349:Patient Compliance; D011177:Postal Service; D012189:Retrospective Studies; D012621:Seasons; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000295:instrumentation / Q000379:methods*; D013696:Temperature
chemical_list: D006454:Hemoglobins
keywords: California; Cohort Studies; Colorectal Neoplasms; Early Detection of Cancer; Hemoglobins; Mass Screening; Patient Compliance; Postal Service; Retrospective Studies; Seasons; Temperature; Transportation