The PAYOR (Payment and Outcomes Research) Lab

Mission

The PAYOR Lab studies the intersection of payment, incentives, and outcomes in healthcare.

Understanding How Payment Shapes Healthcare

The PAYOR Lab (Payment and Outcomes Research) is dedicated to understanding how physician payment systems and reimbursement policies influence provider behavior and healthcare outcomes. Our work integrates clinical insight, health policy analysis, and rigorous economic research to examine how financial incentives shape decision-making in real-world healthcare settings.

Our Focus

The lab investigates a wide range of questions at the intersection of payment, incentives, and outcomes, including:

Evaluating the accuracy and downstream effects of changes to the Medicare Physician Fee Schedule.
Studying how physician compensation models influence provider behavior, clinical decision-making, and patient outcomes.
Assessing the impact of past and proposed policy changes on payment distribution and their effects on healthcare delivery and patient outcomes.

Our Approach

The PAYOR Lab combines expertise in healthcare data with rigorous research methods to generate actionable insights:

Claims and Registry Data: Leveraging national datasets to study real-world physician behavior, compensation, and patient outcomes.
Causal Econometrics: Applying advanced methods to estimate the impact of payment structures and policy changes.
Primary Data Collection: Designing and conducting surveys and other studies to create rich, context-specific analyses.
Policy Modeling: Simulating alternative payment structures to evaluate potential effects on providers, patients, and the system.
Interdisciplinary Collaboration: Partnering with qualitative researchers, survey methodologists, health economists, policy analysts, clinicians, and implementation scientists.

This integrated approach ensures our research is empirically rigorous, policy-relevant, and grounded in real-world practice.

Why PAYOR?

Impact and Vision

The PAYOR Lab seeks to advance the science and practice of healthcare payment systems. We first aim to understand how existing payment structures have influenced physician behavior, clinical decision-making, and patient outcomes. Building on these insights, we design and rigorously test new payment models in real-world clinical settings to evaluate their effects on providers and care delivery.

Ultimately, our vision is to develop evidence-based payment systems that could be adopted nationally—systems that align the incentives of providers and patients, promote high-quality, efficient care, and support a more equitable and sustainable healthcare system.

Publications

Featured Publications

Childers CP, Foe LM, Mujumdar V, Mabry CD, Selzer DJ, Senkowski CK, Ko CY, Tsai TC. Longitudinal Trends in Efficiency and Complexity of Surgical Procedures: Analysis of 1.7 Million Operations Between 2019 and 2023. J Am Coll Surg. 2025;241(5):741–4.

This study directly addressed a concept introduced in the 2026 PFS proposed rule that would reduce wRVUs for most services based on perceived gains in efficiency. This paper analyzed trends in operative times and patient complexity across 1.7 million procedures. It finds that complexity and operative times have generally increased over time, challenging assumptions behind the proposed efficiency adjustment. View in Journal of the American College of Surgeons > | View in PubMed >

Childers CP, Selzer DJ, Green ML, Sutherland MJ, Senkowski CK, Mabry CD. Generating a New CPT Code Set for Adult and Pediatric Appendectomy. JAMA Surg. 2025;160(10):1076–1081.

DOI: https://doi.org/10.1001/jamasurg.2025.2951 | PubMed: https://pubmed.ncbi.nlm.nih.gov/40833763/
This paper develops a revised CPT code set for appendectomy in adults and children, incorporating data from NSQIP and expert review. The goal is to better capture surgical complexity and improve payment accuracy across populations. View in JAMA Surgery > | View in PubMed >

Childers CP, Hu CY, Swisher SG, Wong SL, Chang GJ. Estimated Financial Impact of 2021 Office-Visit Work Relative Unit Updates on Surgical Global Periods. JAMA Surg. 2024;159(9):1087–1089.

Using a cross-sectional analysis, this study estimates how 2021 updates to office-visit wRVUs affected reimbursement as it relates to surgical global periods. The paper identified $100s of millions of dollars that were taken away from surgical providers. View in the NIH National Library of Medicine > | View in PubMed >

Childers CP, Manisundaram NV, Hu CY, Chang GJ. Modifier 22 Use in Fee-for-Service Medicare. JAMA Surg. 2024;159(5):563–569.

This was the first empiric evaluation of Modifier 22 claims in Medicare. It found that average payments were no higher for those cases with Moidifer 22 owing primarily to higher denial rates. View in JAMA Surgery > | View in PubMed >

Childers CP, Petty AM, Selzer DJ, Senkowski CK. Obesity and Work in Abdominal Surgery. J Am Coll Surg. 2025 Feb 27.
View in the Journal of the American College of Surgeons > | View in PubMed >

Using ACS NSQIP data, this study quantifies the impact of BMI on operative time and complication risk across common abdominal surgeries. The results support a modifier or add on code for obesity-related surgical work in payment models.

Full Publication List

Google Scholar
PubMed

Team

Principal Investigator

Christopher P. Childers, MD, PhD

Dr. Childers is the principal investigator of the PAYOR Lab, where he studies the intersection of healthcare payment, physician incentives, and patient outcomes. He completed his general surgery training at UCLA, during which he spent three years in the lab earning a PhD in Health Policy & Management. His research was supported by an AHRQ F32 award and the AAS/AASF Clinical Outcomes Research Fellowship. Dr. Childers subsequently completed a surgical oncology fellowship at MD Anderson Cancer Center. He is now faculty at the University of Washington, where his clinical practice focuses on hepatopancreatobiliary (HPB) surgery. He founded the PAYOR Lab to advance rigorous research on Medicare Physician Fee Schedule impacts, physician compensation models, and evidence-based payment reform. Dr. Childers serves on the American College of Surgeons (ACS) General Surgery Coding & Reimbursement Committee and as the advisor alternate to the AMA RUC for the ACS. He is also actively involved with the Surgical Outcomes Club (SOC), Society of Surgical Oncology (SSO), and American Association of Surgery (AAS).

Dr. Christopher P. Childers' Fred Hutch Cancer Center Provider Page

Collaborators / Advisory Board

The PAYOR Lab benefits from a diverse group of collaborators and advisors spanning academia, clinical organizations, and professional societies. Our collaborators bring expertise in health economics and rigorous methodology, clinical outcomes assessment, and healthcare finance. These relationships extend across the University of Washington, the American College of Surgeons, and other national and international partners, providing guidance, mentorship, and opportunities for collaborative research initiatives.

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