Individualized Comparative Effectiveness of Models Optimizing Patient Safety and Resident Education (iCOMPARE)

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Accession Number

Study Type
Clinical Trial

Collection Type
Open BioLINCC Study See bottom of this webpage for request information

Study Period
July 2015 – December 2016

NHLBI Division

Dataset(s) Last Updated
May 20, 2020


Commercial Use Data Restrictions No

Data Restrictions Based On Area Of Research No


The iCOMPARE trial aimed to compare all-cause mortality of patients cared for by trainees, the education that trainees receive, and the sleep patterns of trainees between internal-medicine residency programs with either standard duty hours or flexible duty hours.


For decades, there has been debate about the effects of the long duty hours of resident physicians. In 2003, the Accreditation Council for Graduate Medical Education (ACGME) established resident duty-hour policies that limited resident workweeks to 80 hours and shifts to 30 hours. Further restrictions that limited shifts to 16 hours for first-year residents (interns) were implemented in 2011.

After the 2011 ACGME policies were implemented, program directors reported a reduced quality of training and professional maturation, increased frequency of handoffs of care, and decreased continuity, without improved patient safety or quality of care.

The iCOMPARE trial compared internal-medicine residency programs with either standard duty hours, as adopted by the ACGME in 2011, or flexible duty hours to address questions concerning the safety of patients who are cared for by the trainees (both interns and residents), the education that trainees receive, and the trainees’ sleep patterns and well-being.


The iCOMPARE trial was comprised of 63 internal medicine residency programs, 32 programs with flexible duty hours and 31 programs with standard duty hours.

Patient Safety:

Patients who were 65.5 years of age or older and who were admitted with one of 17 qualifying medical conditions to a participating hospital during the pretrial year (July 1, 2014, to June 30, 2015) or the trial year (July 1, 2015, to June 30, 2016) were selected. Only patients who were in Medicare fee-for-service for a period of at least 6 months before the index admission and at least 30 days after the index admission were included.

If a patient had multiple qualifying admissions, the first qualifying admission during each of the pretrial and trial years was included. A total of 244,180 patients were included with a total of 264,585 admissions.

Resident Education:

The data from trainees that completed the ACGME annual resident survey, the investigator end-of-year survey, and/or investigator end-of-shift surveys were included. Response rates to the three surveys varied.

The data from faculty that completed the ACGME faculty survey and/or the investigator survey of program directors were included. In the investigator survey, a data-acquisition error limited secondary analyses to 19 flexible and 18 standard programs for year 2015.

Time and Motion Substudy:

A total of 80 interns (first-year residents) who provided consent were observed to determine the amount of time interns spend on direct patient care and education. 44 interns were in flexible programs and 36 interns were in standard programs. Interns in flexible programs were observed for a total of 1072 hours over 96 shifts and interns in standard programs were observed for a total of 1101 hours over 98 shifts.

Sleep and Alertness Substudy:

Data from a total of 398 interns who provided consent were available for analysis of sleepiness. 205 interns were in flexible programs and 193 interns were in standard programs.


iCOMPARE was a cluster-randomized noninferiority trial. Programs selected had at least one affiliated hospital in both the upper half of resident-to-bed ratios and the upper three quartiles of patient volumes for the 17 prespecified medical conditions. A total of 63 programs underwent randomization in a 1:1 ratio to a group with standard duty-hour rules (following the 2011 ACGME duty-hour regulations with its 16-hour limit on intern shift length) or to a group with flexible duty hours, which allowed directors to extend work-hour limits beyond the 16-hour limit.

Patient Safety:

The qualifying medical conditions were chosen for their common treatment on internal-medicine services and their elevated mortality. The qualifying medical conditions were: septicemia, congestive heart failure, stroke, acute myocardial infarction, coronary atherosclerosis, gastrointestinal bleeding, cardiac arrhythmia, renal failure, pneumonia, chronic obstructive pulmonary disease/asthma/bronchitis, pulmonary embolism, acute respiratory disorder, cellulitis, syncope, chest pain, intestinal infection, and acute pancreatitis. All outcomes were ascertained from Medicare claims to ensure uniform measurement across participating hospitals.

The primary outcome for each program was the change in unadjusted 30-day mortality from the pretrial year to the trial year.

Resident Education:

Trainee satisfaction was measured using three surveys: the ACGME annual resident survey, an investigator end-of-year survey, and an investigator end-of-shift survey. ACGME researchers performed and provided analyses of responses to their 2015 and 2016 annual resident surveys. Potential responses were “never,” “rarely,” “sometimes,” “often,” and “very often.” ACGME dichotomized the 5-level response to each component question into “compliant” or “noncompliant”. Investigators administered an end-of-year survey to all trainees in May 2015 in 55 programs (which served as a baseline survey before the start of the trial) and in May 2016 in 62 programs (end-of-trial survey). The 5-level response for each question was dichotomized into a “positive” or “negative” response. The survey ended with the Maslach Burnout Inventory–Human Services Survey, a 22-item scale assessing emotional exhaustion, depersonalization, and perception of personal accomplishment. Investigators administered end-of-shift surveys to all trainees in 60 programs every 2 weeks from September 2015 through April 2016. The surveys reflected trainees’ perceptions of their experience with education, ownership, work intensity, and continuity.

Faculty satisfaction was measured using two surveys: the ACGME faculty survey and an investigator survey of program directors. Using the same process as for ACGME resident surveys, the ACGME provided analyses of responses to their 2015 and 2016 annual faculty surveys. The questions on the investigator survey of program directors were dichotomized in the same manner as the investigator end-of-year survey given to trainees.

The primary outcome for trainee satisfaction with education was their perception of an appropriate balance between clinical demands and education. The primary outcome for faculty satisfaction with education was whether trainees’ workload exceeded their capacity.

Sleep and Alertness Substudy:

12 programs participated in the Sleep and Alertness substudy, 6 in the standard duty group and 6 in the flexible duty group. Coordinators scheduled interns for a single 14-day measurement period, commencing on a Monday, during which the intern underwent continuous sleep–wake measurement by means of actigraphy and completed a brief survey followed by a 3-minute Psychomotor Vigilance Test (PVT-B) on a trial-issued smartphone every morning. Actigraphy data were classified in 1-minute epochs as wake, sleep, or unknown. Each day between 6 a.m. and 9 a.m., interns were asked to complete a brief survey on the smartphone that included a question on the shift that the intern was working, a sleep log (in which they recorded sleep periods during the past 24 hours), a score for sleep quality (on a 5-point scale, from 1 [bad] to 5 [good]), a question on the experience of periods of excessive sleepiness during the past 24 hours (with instructions to check all that apply: none, 12 a.m. to 6 a.m., 6 a.m. to 12 p.m., 12 p.m. to 6 p.m., and 6 p.m. to 12 a.m.), and the score on the Karolinska Sleepiness Scale (on a 9-point scale, from 1 [extremely alert] to 9 [extremely sleepy, fighting sleep]). PVT-B data were inspected and classified as generated in a manner that was adherent with instructions, probably nonadherent, or nonadherent as judged by sleep experts who were not aware of the trial-group assignments.

The primary outcome for the sleep and alertness substudy was sleep duration and morning sleepiness and alertness.

Time and Motion Substudy:

From March through May 2016, time–motion observations were conducted at three flexible and three standard programs located in the mid-Atlantic region. The observations were performed by 23 trained observers. Activity was recorded in milliseconds with the use of custom-built tablet-based software, with choices of direct patient care, education, indirect patient care, handoffs, rounds, or miscellaneous; more than one category could be selected if different types of activities occurred simultaneously. The mean length of observed shifts was 11.2 hours in both flexible and standard programs.

The primary outcome of the time and motion substudy was time spent on direct patient care and education by the trainees.


Patient Safety:

Allowing program directors flexibility in adjusting duty-hour schedules for trainees did not adversely affect 30-day mortality.

Silber JH, Bellini LM, Shea JA, et al. Patient Safety Outcomes under Flexible and Standard Resident Duty-Hour Rules. N Engl J Med. 2019;380(10):905–914. doi:10.1056/NEJMoa1810642

Resident Education:

Interns in flexible programs were less satisfied with their educational experience than were their peers in standard programs, but program directors were more satisfied.

Desai SV, Asch DA, Bellini LM, et al. Education Outcomes in a Duty-Hour Flexibility Trial in Internal Medicine. N Engl J Med. 2018;378(16):1494–1508. doi:10.1056/NEJMoa1800965

Time and Motion Substudy:

There was no significant difference in the proportion of time that medical interns spent on direct patient care and education between programs with standard duty-hour policies and programs with more flexible policies.

Desai SV, Asch DA, Bellini LM, et al. Education Outcomes in a Duty-Hour Flexibility Trial in Internal Medicine. N Engl J Med. 2018;378(16):1494–1508. doi:10.1056/NEJMoa1800965

Sleep and Alertness Substudy:

This trial showed no more chronic sleep loss or sleepiness across trial days among interns in flexible programs than among those in standard programs.

Basner M, Asch DA, Shea JA, et al. Sleep and Alertness in a Duty-Hour Flexibility Trial in Internal Medicine. N Engl J Med. 2019;380(10):915–923. doi:10.1056/NEJMoa1810641

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