Offering Annual Fecal Occult Blood Tests at Annual Flu Shot Clinics Increases Colorectal Cancer Screening Rates

PURPOSE We wanted to determine whether providing home fecal occult blood test (FOBT) kits to eligible patients during influenza inoculation (flu shot) clinics can contribute to higher colorectal cancer screening (CRCS) rates. METHODS The study was time randomized. On 8 dates of an annual flu shot clinic at the San Francisco General Hospital, patients were offered flu shots as usual (control group) and on 9 other dates, patients were offered both flu shots and FOBT kits (intervention group). RESULTS The study included 514 patients aged 50 to 79 years, with 246 in the control group and 268 in the intervention group. At the conclusion of flu season, FOBT screening rates increased by 4.4 percentage points from 52.9% at baseline to 57.3% (P = .07) in the control group, and increased by 29.8 percentage points from 54.5% to 84.3% (P < .001) in the intervention group, with the change among intervention participants 25.4 percentage points greater than among control participants (P value for change difference < .001). Among patients initially due for CRCS, 20.7% in the control group and 68.0% in the intervention group were up-to-date at the conclusion of the study (P < .001). In multivariate analyses, the odds ratio for becoming up-to-date with screening in the intervention group (vs the control group) was 11.3 (95% CI, 5.8-22.0). CONCLUSIONS Offering FOBT kits during flu shot clinics dramatically increased the CRCS rate for flu shot clinic attendees. Pairing home FOBT kits with annual flu shots may be a useful strategy to improve CRCS rates in other primary care or public health settings.