Table 1 The database criteria for the diagnosis of IBD, UC, CD and IBDU

IBD

All patients had to have at least one hospitalization, or four physician claims, within a two year period for a diagnosis of IBD.

  • IBD patients were then classified as UC, CD or IBDU as follows.

  • Each medical contact for the Physician Billing claims database was scored as + 1 (UC) or -1 (CD).

  • Each medical contact for the Discharge Abstract database was scored as +2 (UC) or -2 (CD).

  • A cumulative score was calculated for each patient.

UC

Patients with a cumulative score greater than +2.

CD

Patients with a cumulative score less than -2.

IBDU

Patients with a cumulative score equal to, or between, -2 and +2.