The 2-day written examination consisted of between 500 (pre-1993) and 550 items of the multiple-choice, single-best answer, and matching type. Items covered the broad domain of internal medicine from traditional subspecialty tracks with the following categories: cardiovascular (13%), pulmonary (11%), endocrinology (10%), hematology/oncology (14%), renal/electrolytes (12%), infectious disease (9%), allergy (5%), gastroenterology (11%), rheumatology (8%), neurology (5%), and miscellaneous (2%). Other important cross-content areas (eg, dermatology, geriatric medicine, disease prevention, substance abuse, rehabilitation medicine) were also covered. Approximately 56% of the items were ambulatory medicine–related items, 19% were in-hospital items, 10% were critical care–related items, and 15% were items in miscellaneous categories. Percentages varied minimally from year to year but remained relatively constant during the past 10 years.