Mobile health technologies are advancing rapidly as smartphone use increases. Patients with inflammatory bowel disease (IBD) might be managed remotely through smartphone applications, but no tools are yet available. We tested the ability of an IBD monitoring tool, which can be used with mobile technologies, to assess disease activity in patients with Crohn’s disease (CD) or ulcerative colitis (UC).

We performed a prospective observational study to develop and validate a mobile health index for CD and UC, which monitors IBD disease activity using patient-reported outcomes. We collected data from disease-specific questionnaires completed by 110 patients with CD and 109 with UC who visited the University of California, Los Angeles, Center for IBD from May 2013 through January 2014. Patient-reported outcomes were compared with clinical disease activity index scores to identify factors associated with disease activity. Index scores were validated in 301 patients with CD and 265 with UC who visited 3 tertiary IBD referral centers (in California or Europe) from April 2014 through March 2015.

We assessed activity of CD based on liquid stool frequency, abdominal pain, patient well-being, and patient-assessed disease control, and activity of UC based on stool frequency, abdominal pain, rectal bleeding, and patient-assessed disease control. The indices identified clinical disease activity with area under the receiver operating characteristic curve values of 0.90 in patients with CD and 0.91 in patients with UC. They identified endoscopic activity with area under the receiver operating characteristic values of 0.63 in patients with CD and 0.82 in patients with UC. Both scoring systems responded to changes in disease activity (P < .003). The intraclass correlation coefficient for test-retest reliability was 0.94 for CD and for UC.

We developed and validated a scoring system to monitor disease activity in patients with CD and UC that can be used with mobile technologies. The indices identified clinical disease activity with area under the receiver operating characteristic curve values of 0.9 or higher in patients with CD or UC, and endoscopic activity in patients with UC but not CD.