ABIM has the most fully specified pathway. It cuts categorical IM to 24 months, with at least 20 months of direct patient care, and requires at least 36 months of mentored research at 80% effort. The IM exam comes in summer of PGY-4 for subspecialty-track trainees and summer of PGY-5 for IM-only trainees. Subspecialty clinical minimums are unchanged, so total length depends on the fellowship: 6 years for a 12-month-clinical subspecialty and 7 years for cardiology.

The penalty for leaving is real. A trainee who switches to a clinical career must make up all the clinical time of the standard route. ABIM's example is a cardiology trainee who then needs 6 total years, 5 of them clinical. ABIM lays out what basic-scientist and clinical-investigator training should include (degree coursework if the trainee does not already have one, mentor qualifications, environment), but it does not require a PhD for entry. The December 2025 ABIM Policies and Procedures PDF matches the web page.

The ABP runs two complementary routes. The IRP lets an MD/PhD spend up to 11 research months inside residency. It does not shorten time to the general pediatrics exam: the trainee still needs a fourth year with at least 6 clinical months, normally fellowship year 1, so the IRP functions as early protected research time. The ARP saves a year of residency by moving into fellowship after 2 years, but it fixes fellowship at 4 years and excludes the trainee from subspecialty fast-tracking.

Fast-tracking is a separate PhD-linked option: a fellow with a relevant PhD or sustained research record can have up to 1 year of fellowship and the scholarly activity requirement waived. It is available only after 3 core years. Program websites and the Council of Pediatric Subspecialties describe the IRP as including up to 12 months of research; the ABP Booklet of Information (January 2026) says a maximum of 11, and the board's number should govern. The ABP's ARP page lists general pediatrics curricular requirements effective July 2025.

The Holman pathway keeps standard residency length and moves time from clinical work to research. Current ABR text (page modified October 1, 2026) lists 12 to 21 months of dedicated research time. Older literature, such as a 2019 NCI workshop report, described 18 to 21 protected months, so the minimum appears to have been lowered; no ABR announcement giving the date was found. The standard DR route also allows up to 16 months of research, which narrows the advantage of Holman for DR. That fits a 2019 AJR analysis by Wallner and colleagues titled "Opportunities Lost for Diagnostic Radiology," which notes that the expected even split between DR and RO participants did not materialize after 18 years.

The ABR also says R38-funded trainees may be eligible for certification if they meet requirements equivalent to the Holman Research Pathway. For RO, the ACGME's Holman page describes 27 clinical and 21 research months with a reduced external-beam case minimum; the case-number figures (350 versus 450) come from older sources and may be out of date.

The PSRP does not change clinical requirements. It adds at least one research year beyond the 6 months already allowed in core training, and it relaxes the time-away rule. Its main value is recognition, plus credit toward lifelong learning under Continuing Certification. ABPath expressly declines to oversee the research, and trainees may enter or leave at any time. The AAMC describes programs offering up to 3 years of protected research across residency and fellowship. For residents starting in 2025 or later, AP-only and CP-only training needs at least 18 structured months and may include up to 6 months of research.

The Investigative Training Track keeps clinical exposure equal to standard residency through the 225% clinical-time accounting. In practice it lengthens dermatology training to about 4 years to buy roughly 1.75 years of research. Approval is per candidate and cannot be requested before January 1 of PGY-2, so programs cannot promise the track at the Match. Some programs (UCSD, for example) instead advertise "ABD approved" research positions that finish in 3 years with condensed research time. The ABD website still has a Pediatric Dermatology Research Track page, but the current residency-training menu lists a "Dermatology Residency Track with Pediatric Dermatology Focus," so check which is current before advising a trainee.

The ABA approves curricula, not people. A department with an accreditation cycle of 3 years or more can build a 60-month research curriculum with up to 23 months of research (38%) without separate Credentials Committee review, as long as it meets the clinical anesthesia minimums. Once research passes 6 months, the program must report the mentor, an oversight committee and the work product. The ABA's "Alternate Entry Path – Research and Fellowship Pathway" is for internationally trained anesthesiologists and has nothing to do with residents. The 2025 Exceptional Clinician Pathway is also an international route.

Only child neurology has a board-defined research option: a basic neuroscience research year in place of the fifth (pediatrics, IM or FM) year, approved person by person. Baylor and other programs combine it with research electives to give up to 18 uninterrupted months. Adult neurology and psychiatry research tracks are built entirely within ACGME program requirements. A 2026 Academic Psychiatry paper on the new Synapse organization says there are no established guidelines for research training for aspiring physician-scientists in psychiatry tracks. The 2003 IOM report had already recorded that ABPN had no research policy. The ABPN "Academic Pathway" pilot is for internationally trained specialists.

ABS still requires five clinical years with at least 48 weeks of clinical activity each, and research time sits outside them. The 2026–2027 Booklet lists a six-year option for residents in the ACS Surgeon Scientist Pathway, and the ABS leave policy requires programs to request that option for each SSTP resident. Dedicated research outside the SSTP needs no prior ABS approval. The SSTP came out of Blue Ribbon Committee II (ACS, ASA and ABS; report October 2024). According to a Viewpoint column in the February 2026 Bulletin of the ACS, the pilot starts in the 2026–2027 Match as a separately matchable NRMP track with reversion, using a 5+2 model with continued research during clinical years; Penn and Weill Cornell are among the sites listing SSTP Match codes. These are the authors' descriptions of a pilot whose outcomes are still unknown.

The ABS weekly clinical minimums also changed: the 2024–25 booklet required 232 weeks of clinical surgery (180 in general surgery content areas), and the 2026–27 booklet requires 216 and 168. ABOS, ABU, ABCRS and ABNS have no pathway. ABU limits dedicated research to 3 to 6 months, and ABNS excludes research from the 54 clinical months.

ABOHNS has no pathway. Its 2021–2022 decisions on NIH R25 research residencies mean research is added on top of clinical training: residency is extended month for month, and clinical work during the research period earns no credit. The ACGME Review Committee confirmed this in an April 2023 FAQ. The result is program-level 7-year research tracks (Iowa, USC and others).