Clifford Y. Ko

49.4k citations

533 papers · 36.8k indexed · 17 hit papers · h-index 98

Surgery top 0.01%
Oncology top 0.05%
Cardiology and Cardiovascular Medicine top 0.1%
Pulmonary and Respiratory Medicine top 0.1%
Epidemiology top 0.5%

Co-authors: Karl Y. Bilimoria Bruce L. Hall Melinda A. Maggard Mark E. Cohen Andrew K. Stewart David P. Winchester David S. Zingmond Karen Richards
Topics: Cardiac, Anesthesia and Surgical Outcomes (217 papers)Colorectal Cancer Surgical Treatments (82 papers)Colorectal Cancer Screening and Detection (57 papers)
Cited by: Surgery Oncology Geriatrics and Gerontology
Journals: New England Journal of Medicine JAMA Journal of Clinical Oncology
Partner nations: United States Canada United Kingdom

In The Last Decade

Clifford Y. Ko

510 papers receiving 35.9k citations

Hit Papers

5 papers align trajectories

What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

The National Cancer Data Base: A Powerful Initiative to Improve Cancer Care in the United States

2008 1.6k citations Karl Y. Bilimoria, Andrew K. Stewart et al. profile →
Development and Evaluation of the Universal ACS NSQIP Surgical Risk Calculator: A Decision Aid and Informed Consent Tool for Patients and Surgeons

2013 1.3k citations Karl Y. Bilimoria, Clifford Y. Ko et al. profile →
Colon Cancer Survival Rates With the New American Joint Committee on Cancer Sixth Edition Staging

2004 1.3k citations Clifford Y. Ko et al. profile →
Toward Robust Information: Data Quality and Inter-Rater Reliability in the American College of Surgeons National Surgical Quality Improvement Program

2009 1.2k citations Karen Richards, Clifford Y. Ko et al. profile →
The Aging Population and Its Impact on the Surgery Workforce

2003 664 citations David A. Etzioni, Clifford Y. Ko et al. Annals of Surgery profile →
American College of Surgeons and Surgical Infection Society: Surgical Site Infection Guidelines, 2016 Update

2016 651 citations Kristen A. Ban, Clifford Y. Ko et al. profile →
Does Surgical Quality Improve in the American College of Surgeons National Surgical Quality Improvement Program

2009 625 citations Bruce L. Hall, Karen Richards et al. Annals of Surgery profile →
Underlying Reasons Associated With Hospital Readmission Following Surgery in the United States

2015 588 citations Ryan P. Merkow, Bruce L. Hall et al. profile →
Optimal Preoperative Assessment of the Geriatric Surgical Patient: A Best Practices Guideline from the American College of Surgeons National Surgical Quality Improvement Program and the American Geriatrics Society

2012 574 citations Ronnie A. Rosenthal, Ryan P. Merkow et al. profile →
Extent of Surgery Affects Survival for Papillary Thyroid Cancer

2007 487 citations Karl Y. Bilimoria, Clifford Y. Ko et al. Annals of Surgery profile →
First Report from the American College of Surgeons Bariatric Surgery Center Network

2011 481 citations Matthew M. Hutter, Clifford Y. Ko et al. Annals of Surgery profile →
Quality Improvement in Surgery: the American College of Surgeons National Surgical Quality Improvement Program Approach

2010 452 citations Angela M. Ingraham, Karen Richards et al. profile →
Optimizing ACS NSQIP Modeling for Evaluation of Surgical Quality and Risk: Patient Risk Adjustment, Procedure Mix Adjustment, Shrinkage Adjustment, and Surgical Focus

2013 446 citations Mark E. Cohen, Clifford Y. Ko et al. profile →
Small Bowel Cancer in the United States

2008 442 citations Karl Y. Bilimoria, Clifford Y. Ko et al. Annals of Surgery profile →
Preoperative Predictors of Weight Loss Following Bariatric Surgery: Systematic Review

2011 426 citations Masha J. Livhits, Clifford Y. Ko et al. profile →
Optimal Perioperative Management of the Geriatric Patient: A Best Practices Guideline from the American College of Surgeons NSQIP and the American Geriatrics Society

2016 367 citations Ronnie A. Rosenthal, Marcia M. Russell et al. profile →
National Cluster-Randomized Trial of Duty-Hour Flexibility in Surgical Training

2016 279 citations Karl Y. Bilimoria, Mark E. Cohen et al. profile →

Peers

Countries citing papers authored by Clifford Y. Ko

Since Specialization

Citations

This map shows the geographic impact of Clifford Y. Ko's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Clifford Y. Ko with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Clifford Y. Ko more than expected).

Fields of papers citing papers by Clifford Y. Ko

Since Specialization

Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Clifford Y. Ko. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Clifford Y. Ko. The network helps show where Clifford Y. Ko may publish in the future.

Co-authorship network of co-authors of Clifford Y. Ko

This figure shows the co-authorship network connecting the top 25 collaborators of Clifford Y. Ko. A scholar is included among the top collaborators of Clifford Y. Ko based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Clifford Y. Ko. Clifford Y. Ko is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

Sort: Min cites: Since: Top N: Style:

20 of 20 papers shown

#	Work	Indexed citations
1	Evaluating agreement between clinic- and patient-reported outcomes for weight and co-morbidities at 1 year after bariatric surgery 2022 ·Surgery for Obesity and Related Diseases ·(unknown),Meridith E. Greene,Clifford Y. Ko,Mark E. Cohen,(unknown),(unknown),Matthew M. Hutter	3
2	Health‐related quality of life outcomes after neoadjuvant chemoradiotherapy for rectal cancer in NRG Oncology/NSABP R‐04 2022 ·Cancer ·Patricia A. Ganz,Ron D. Hays,Karen L. Spritzer,André Rogatko,Clifford Y. Ko,Linda H. Colangelo,Amit Arora,Judith O. Hopkins,Terry Evans,Greg Yothers	6
3	Surgical Outcomes in Canada and the United States: An Analysis of the ACS‐NSQIP Clinical Registry 2022 ·World Journal of Surgery ·Peter Cram,Mark E. Cohen,Clifford Y. Ko,Bruce E. Landon,Bruce L. Hall,Timothy Jackson	5
4	Same-day discharge is not associated with increased readmissions or complications after thyroid operations 2019 ·Surgery ·(unknown),Masha J. Livhits,Clifford Y. Ko,Michael W. Yeh	14
5	Injury-specific variables improve risk adjustment and hospital quality assessment in severe traumatic brain injury 2019 ·The Journal of Trauma: Injury, Infection, and Critical Care ·Aaron J. Dawes,Greg D. Sacks,Jack Needleman,Robert H. Brook,Brian S. Mittman,Clifford Y. Ko,H. Gill Cryer	8
6	Surgical Technical Evidence Review for Gynecologic Surgery Conducted for the Agency for Healthcare Research and Quality Safety Program for Improving Surgical Care and Recovery 2019 ·Obstetrical & Gynecological Survey ·Eleftheria Kalogera,Gregg Nelson,Jessica Liu,(unknown),Clifford Y. Ko,Elizabeth C. Wick,Sean C. Dowdy	2
7	Effect of Diagnosis on Outcomes in the Setting of Enhanced Recovery Protocols 2018 ·Diseases of the Colon & Rectum ·Kristen A. Ban,Julia R. Berian,Jason B. Liu,Clifford Y. Ko,Liane S. Feldman,Julie K. Thacker	18
8	Expanding the scope of quality measurement in surgery to include nonoperative care: Results from the American College of Surgeons National Surgical Quality Improvement Program emergency general surgery pilot 2017 ·The Journal of Trauma: Injury, Infection, and Critical Care ·(unknown),Clifford Y. Ko,Paul E. Bankey,Chris Cribari,H. Gill Cryer,José J. Diaz,Therèse M. Duane,S. Morad Hameed,Matthew M. Hutter,Michael H. Metzler,Justin L. Regner,Patrick M. Reilly,H. David Reines,Jason L. Sperry,Kristan Staudenmayer,Garth H. Utter,Marie Crandall,Karl Y. Bilimoria,Avery B. Nathens	36
9	Improving quality in geriatric surgery: A blueprint from the American College of Surgeons. 2016 ·PubMed ·Marcia M. Russell,Julia R. Berian,Ronnie A. Rosenthal,Clifford Y. Ko	8
10	Measuring Risk-Adjusted Value Using Medicare and ACS-NSQIP 2014 ·Annals of Surgery ·Elise H. Lawson,David S. Zingmond,Anne M. Stey,Bruce L. Hall,Clifford Y. Ko	14
11	Using Both Clinical Registry and Administrative Claims Data to Measure Risk-adjusted Surgical Outcomes 2014 ·Annals of Surgery ·Elise H. Lawson,Rachel Louie,David S. Zingmond,Greg D. Sacks,Robert H. Brook,Bruce L. Hall,Clifford Y. Ko	37
12	Nodal Evaluation in Wilms' Tumors 2010 ·Annals of Surgery ·Mehul V. Raval,Karl Y. Bilimoria,David J. Bentrem,Andrew K. Stewart,David P. Winchester,Clifford Y. Ko,Marleta Reynolds	30
13	Effect of Postdischarge Morbidity and Mortality on Comparisons of Hospital Surgical Quality 2010 ·Annals of Surgery ·Karl Y. Bilimoria,Mark E. Cohen,Angela M. Ingraham,David J. Bentrem,Karen Richards,Bruce L. Hall,Clifford Y. Ko	112
14	Effect of Subjective Preoperative Variables on Risk-Adjusted Assessment of Hospital Morbidity and Mortality 2009 ·Annals of Surgery ·Mark E. Cohen,Karl Y. Bilimoria,Clifford Y. Ko,Karen Richards,Bruce L. Hall	48
15	Variability in Length of Stay After Colorectal Surgery 2009 ·Annals of Surgery ·Mark E. Cohen,Karl Y. Bilimoria,Clifford Y. Ko,Karen Richards,Bruce L. Hall	84
16	Laparoscopic-assisted vs. Open Colectomy for Cancer: Comparison of Short-term Outcomes from 121 Hospitals 2008 ·Journal of Gastrointestinal Surgery ·Karl Y. Bilimoria,David J. Bentrem,Ryan P. Merkow,Heidi Nelson,Edward Wang,Clifford Y. Ko,Nathaniel J. Soper	94
17	Disparities in the Utilization of High-Volume Hospitals for Total Knee Replacement 2008 ·Journal of the National Medical Association ·Nelson F. SooHoo,David S. Zingmond,Clifford Y. Ko	58
18	A population‐based study of colorectal cancer test use 2004 ·Cancer ·David A. Etzioni,Ninez A. Ponce,Susan H. Babey,Benjamin A. Spencer,E. Richard Brown,Clifford Y. Ko,Neetu Chawla,Nancy Breen,Carrie N. Klabunde	95
19	Palliative care for colorectal cancer 2004 ·Surgical Oncology Clinics of North America ·Farin Amersi,Michael J. Stamos,Clifford Y. Ko	14
20	Use of the Health and Activities Limitation Index as a Measure of Quality of Life in Obesity 2002 ·Obesity Research ·Edward H. Livingston,Clifford Y. Ko	38

About Clifford Y. Ko

Clifford Y. Ko is a scholar working on Cardiology and Cardiovascular Medicine, Surgery and Geriatrics and Gerontology, having authored 533 papers that have together received 36.8k indexed citations. Recurring topics across this work include Cardiac, Anesthesia and Surgical Outcomes (217 papers), Colorectal Cancer Surgical Treatments (82 papers) and Colorectal Cancer Screening and Detection (57 papers). The work is most often cited by research in Surgery (20.0k citations), Oncology (12.1k citations) and Geriatrics and Gerontology (1.7k citations). Clifford Y. Ko has collaborated with scholars based in United States, Canada and United Kingdom. Frequent co-authors include Karl Y. Bilimoria, Bruce L. Hall, Melinda A. Maggard, Mark E. Cohen, Andrew K. Stewart, David P. Winchester, David S. Zingmond, Karen Richards, Ryan P. Merkow and David J. Bentrem. Their work appears in journals such as New England Journal of Medicine, JAMA and Journal of Clinical Oncology.

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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