Roy Hajjar

768 total citations
41 papers, 408 citations indexed

About

Roy Hajjar is a scholar working on Surgery, Molecular Biology and Pulmonary and Respiratory Medicine. According to data from OpenAlex, Roy Hajjar has authored 41 papers receiving a total of 408 indexed citations (citations by other indexed papers that have themselves been cited), including 24 papers in Surgery, 11 papers in Molecular Biology and 11 papers in Pulmonary and Respiratory Medicine. Recurrent topics in Roy Hajjar's work include Gut microbiota and health (10 papers), Colorectal Cancer Surgical Treatments (5 papers) and Gastric Cancer Management and Outcomes (5 papers). Roy Hajjar is often cited by papers focused on Gut microbiota and health (10 papers), Colorectal Cancer Surgical Treatments (5 papers) and Gastric Cancer Management and Outcomes (5 papers). Roy Hajjar collaborates with scholars based in Canada, United States and France. Roy Hajjar's co-authors include Manuela M. Santos, Carole Richard, Herawaty Sebajang, Frank Schwenter, Gabriel Chan, Annie Calvé, Gabriela Fragoso, Pierre Y. Garneau, Frédéric Mercier and Rasmy Loungnarath and has published in prestigious journals such as SHILAP Revista de lepidopterología, Gastroenterology and Clinical Cancer Research.

In The Last Decade

Roy Hajjar

35 papers receiving 401 citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Roy Hajjar Canada 12 145 128 69 65 52 41 408
Qiang Huang China 14 111 0.8× 158 1.2× 165 2.4× 127 2.0× 90 1.7× 29 499
Hongying Pan China 14 160 1.1× 76 0.6× 34 0.5× 29 0.4× 35 0.7× 49 552
Sarah Weber Germany 12 287 2.0× 58 0.5× 107 1.6× 63 1.0× 34 0.7× 22 618
Yongtong Cao China 13 253 1.7× 65 0.5× 51 0.7× 38 0.6× 36 0.7× 42 603
Fikret Ezbercı Türkiye 12 76 0.5× 295 2.3× 39 0.6× 103 1.6× 19 0.4× 40 589
Lígia Yukie Sassaki Brazil 12 250 1.7× 154 1.2× 68 1.0× 31 0.5× 92 1.8× 82 687
Maria Delgado Spain 7 225 1.6× 100 0.8× 29 0.4× 54 0.8× 56 1.1× 15 574
David Niccum United States 7 241 1.7× 63 0.5× 51 0.7× 165 2.5× 26 0.5× 9 448
C. Ganesh Pai India 16 95 0.7× 351 2.7× 106 1.5× 63 1.0× 34 0.7× 56 686
Jun Sik Yoon South Korea 14 273 1.9× 107 0.8× 53 0.8× 25 0.4× 71 1.4× 42 764

Countries citing papers authored by Roy Hajjar

Since Specialization
Citations

This map shows the geographic impact of Roy Hajjar'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 Roy Hajjar with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Roy Hajjar more than expected).

Fields of papers citing papers by Roy Hajjar

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Roy Hajjar. 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 Roy Hajjar. The network helps show where Roy Hajjar may publish in the future.

Co-authorship network of co-authors of Roy Hajjar

This figure shows the co-authorship network connecting the top 25 collaborators of Roy Hajjar. A scholar is included among the top collaborators of Roy Hajjar 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 Roy Hajjar. Roy Hajjar is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Reynolds, Ian S., Roy Hajjar, Sidrah Khan, et al.. (2025). Perineal wound complications after proctectomy for Crohn’s disease: the impact of the omental pedicle flap and predictors of return to the operating room. Journal of Gastrointestinal Surgery. 29(6). 102048–102048.
2.
3.
Hajjar, Roy, Annie Calvé, Gabriela Fragoso, et al.. (2025). Initial gut microbiota composition is a determining factor in the promotion of colorectal cancer by oral iron supplementation: evidence from a murine model. Microbiome. 13(1). 100–100. 1 indexed citations
4.
Hajjar, Roy, Carole Richard, & Manuela M. Santos. (2024). The gut barrier as a gatekeeper in colorectal cancer treatment. Oncotarget. 15(1). 562–572.
5.
Hajjar, Roy, et al.. (2023). A271 THE MODULATION OF INTESTINAL INFLAMMATION BY PARABACTEROIDES GOLDSTEINII IN EXPERIMENTAL MURINE COLITIS. Journal of the Canadian Association of Gastroenterology. 6(Supplement_1). 86–87. 1 indexed citations
6.
Hajjar, Roy, Gabriela Fragoso, Annie Calvé, et al.. (2023). Modulating Gut Microbiota Prevents Anastomotic Leak to Reduce Local Implantation and Dissemination of Colorectal Cancer Cells after Surgery. Clinical Cancer Research. 30(3). 616–628. 10 indexed citations
7.
Hajjar, Roy, et al.. (2023). Inulin impacts tumorigenesis promotion by colibactin-producing Escherichia coli in ApcMin/+ mice. Frontiers in Microbiology. 14. 1067505–1067505. 11 indexed citations
8.
Hajjar, Roy, et al.. (2023). Long-term follow-up of a cohort with post sleeve gastrectomy leaks: results of endoscopic treatment and salvage surgery. Surgical Endoscopy. 37(12). 9358–9365. 4 indexed citations
9.
Hajjar, Roy, Gabriela Fragoso, Annie Calvé, et al.. (2022). Prevalence of pks + bacteria and enterotoxigenic Bacteroides fragilis in patients with colorectal cancer. Gut Pathogens. 14(1). 51–51. 22 indexed citations
10.
Hajjar, Roy, et al.. (2021). High-grade neuroendocrine small-cell carcinoma of the anal canal: longterm remission with chemoradiotherapy. Journal of Clinical and Translational Research. 7(1). 121–126. 1 indexed citations
11.
Hajjar, Roy, et al.. (2021). Conservative Management of Obesity in Kidney Transplant Candidates. Journal of Renal Nutrition. 32(3). 347–353. 5 indexed citations
12.
Calvé, Annie, et al.. (2021). Oral iron supplementation after antibiotic exposure induces a deleterious recovery of the gut microbiota. BMC Microbiology. 21(1). 259–259. 21 indexed citations
13.
Hajjar, Roy, Gabriela Fragoso, Annie Calvé, et al.. (2021). Improvement of colonic healing and surgical recovery with perioperative supplementation of inulin and galacto-oligosaccharides. Clinical Nutrition. 40(6). 3842–3851. 20 indexed citations
14.
Hajjar, Roy & Gabriel Chan. (2020). Anti-tumor necrosis factor agents and COVID-19: A word of caution. Journal of Clinical and Translational Research. 6(3). 94–96. 1 indexed citations
15.
Hajjar, Roy, et al.. (2020). Anisakiasis in a Canadian patient with incarcerated epigastric hernia. IDCases. 20. e00715–e00715. 1 indexed citations
16.
Hajjar, Roy, et al.. (2020). <p><em>Raoultella ornithinolytica</em>: Emergence and Resistance</p>. Infection and Drug Resistance. Volume 13. 1091–1104. 71 indexed citations
17.
Chan, Gabriel, Roy Hajjar, Pierre Y. Garneau, et al.. (2019). Prospective study of the changes in pharmacokinetics of immunosuppressive medications after laparoscopic sleeve gastrectomy. American Journal of Transplantation. 20(2). 582–588. 18 indexed citations
18.
Hajjar, Roy, Mohammed A. Al‐Harthi, Carole Richard, F. Gougeon, & Rasmy Loungnarath. (2019). Pelvic Aggressive Angiomyxoma: Major Challenges in Diagnosis and Treatment. Cureus. 11(4). e4419–e4419. 7 indexed citations
19.
Hajjar, Roy, Pierre Dubé, Andrew Mitchell, & Lucas Sidéris. (2019). Combined Mucinous and Neuroendocrine Tumours of the Appendix Managed with Surgical Cytoreduction and Oxaliplatin-based Hyperthermic Intraperitoneal Chemotherapy. Cureus. 11(1). e3894–e3894. 6 indexed citations
20.
Hajjar, Roy, et al.. (2018). Community-acquired infection to Raoultella ornithinolytica presenting as appendicitis and shock in a healthy individual. Journal of Surgical Case Reports. 2018(5). rjy097–rjy097. 15 indexed citations

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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