FIT indication was determined based on resident or attending physician notes. The history of present illness, physical exam, and assessment and plan section of notes were reviewed by the lead author for a specific statement of indication for FIT or for evidence of clinical presentation for which FIT could reasonably be ordered. Indications were iteratively reviewed and collapsed into 6 different categories: anemia, iron deficiency with or without anemia, overt GIB, suspected GIB/miscellaneous, non-bloody diarrhea, and no indication identified. Overt GIB was defined as reported or witnessed hematemesis, coffee-ground emesis, hematochezia, bright red blood per rectum, or melena irrespective of time frame (current or remote) or chronicity (acute, subacute, or chronic). In cases where signs of overt bleed were not witnessed by medical professionals, determination of conditions such as melena or coffee-ground emesis were made based on health care providers’ assessment of patient history as documented in his or her notes. Suspected GIB/miscellaneous was defined with the following parameters: any new drop in hemoglobin, abdominal pain, anorectal pain, non-bloody vomiting, hemoptysis, isolated rising blood urea nitrogen, or patient noticing blood on self, clothing, or in the commode without an identified source. Patients who were anemic and found to have iron deficiency on recent lab studies (within 6 months) were reflexively categorized into iron deficiency with or without anemia as opposed to the “anemia” category, which was comprised of any anemia without recent iron studies or non-iron deficient anemia. FIT result was determined by test result entry in Epic, with results either reading positive or negative.
Diagnostic follow-up, for our purposes, was defined as receipt of an invasive procedure or surgery, including esophagogastroduodenoscopy (EGD), colonoscopy, flexible sigmoidoscopy, diagnostic and/or therapeutic abdominal surgical intervention, or any combination of these. Results of diagnostic follow-up were coded as normal or abnormal. A normal result was determined if all procedures performed were listed as normal or as “no pathological findings” on the operative or endoscopic report. Any reported pathologic findings on the operative/endoscopic report were coded as abnormal.
Statistical Analysis
Proportions were used to describe demographic characteristics of patients who received a FIT in acute hospital settings. Bivariable tables and Chi-square tests were used to compare indications and outcomes for FIT-positive and FIT-negative patients. The association between receipt of an invasive diagnostic follow-up (outcome) and the results of an inpatient FIT (predictor) was assessed using multivariable log-binomial regression to calculate risk ratios (RRs) and corresponding 95% confidence intervals. Log-binomial regression was used over logistic regression given that adjusted odds ratios generated by logistic regression often overestimate the association between the risk factor and the outcome when the outcome is common,23 as in the case of diagnostic follow-up. The model was adjusted for variables selected a priori, specifically, age, gender, and FIT indication. Chi-square analysis was used to compare the proportion of abnormal findings on diagnostic follow-up by FIT result (negative vs positive).
Results
During the 8-month study period, there were 2718 FITs ordered and completed in the acute care setting, compared to 44,662 FITs ordered and completed in the outpatient setting (5.7% performed during acute care).
Among the 400 charts reviewed, 7 were excluded from the analysis because they were duplicates from the same patient, and 11 were excluded due to insufficient information in the patient’s medical record, resulting in 382 patients included in the analysis. Patient demographic characteristics are described in Table 1. Patients were predominantly Hispanic/Latino or Black/African American (51.0% and 32.5%, respectively), a majority had insurance through the county health system (50.5%), and most were male (58.1%). The average age of those receiving FIT was 52 years (standard deviation, 14.8 years), with 40.8% being under the age of 50. For a majority of patients, FIT was ordered in the ED by emergency medicine providers (79.8%). The remaining FITs were ordered by providers in 12 different inpatient departments. Of the FITs ordered, 35.1% were positive.
