Christopher J. O’Callaghan

13.0k total citations · 1 hit paper
131 papers, 5.9k citations indexed

About

Christopher J. O’Callaghan is a scholar working on Oncology, Pulmonary and Respiratory Medicine and Cancer Research. According to data from OpenAlex, Christopher J. O’Callaghan has authored 131 papers receiving a total of 5.9k indexed citations (citations by other indexed papers that have themselves been cited), including 56 papers in Oncology, 36 papers in Pulmonary and Respiratory Medicine and 18 papers in Cancer Research. Recurrent topics in Christopher J. O’Callaghan's work include Colorectal Cancer Treatments and Studies (41 papers), Gastric Cancer Management and Outcomes (18 papers) and Lung Cancer Treatments and Mutations (18 papers). Christopher J. O’Callaghan is often cited by papers focused on Colorectal Cancer Treatments and Studies (41 papers), Gastric Cancer Management and Outcomes (18 papers) and Lung Cancer Treatments and Mutations (18 papers). Christopher J. O’Callaghan collaborates with scholars based in Canada, Australia and United States. Christopher J. O’Callaghan's co-authors include Bryan Williams, L. Robbin Lindsay, Dominique Charron, Ian K. Barker, M. Bigras-Poulin, Daren K. Heyland, Abdel Maarouf, Peter Dodek, Graeme Rocker and N. H. Ogden and has published in prestigious journals such as Journal of Clinical Oncology, Applied and Environmental Microbiology and Neurology.

In The Last Decade

Christopher J. O’Callaghan

126 papers receiving 5.6k citations

Hit Papers

Disease-Free Survival Versus Overall Survival As a Primar... 2005 2026 2012 2019 2005 100 200 300 400 500
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.

  1. Disease-Free Survival Versus Overall Survival As a Primary End Point for Adjuvant Colon Cancer Studies: Individual Patient Data From 20,898 Patients on 18 Randomized Trials
    2005 520 citations Christopher J. O’Callaghan et al. Journal of Clinical Oncology profile →

Peers — A (Enhanced Table)

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

Name h Career Trend Papers Cites
Christopher J. O’Callaghan Canada 36 1.5k 1.5k 1.4k 1.4k 666 131 5.9k
Robert G. Hamilton United States 64 1.0k 0.7× 341 0.2× 193 0.1× 686 0.5× 1.2k 1.8× 335 14.4k
Richard D. Pearson United States 53 4.7k 3.2× 1.4k 0.9× 340 0.2× 1.5k 1.1× 153 0.2× 198 8.8k
Gabriella Serio Italy 31 1.1k 0.8× 135 0.1× 851 0.6× 319 0.2× 811 1.2× 181 6.1k
Thomas Schneider Germany 56 476 0.3× 738 0.5× 1.0k 0.7× 2.2k 1.6× 1.1k 1.6× 332 11.1k
John D. Mathews Australia 46 1.0k 0.7× 114 0.1× 311 0.2× 780 0.6× 907 1.4× 202 8.6k
Richard A. Kaslow United States 61 849 0.6× 1.2k 0.8× 1.1k 0.7× 6.6k 4.8× 658 1.0× 221 19.8k
Gail Hayward United Kingdom 39 298 0.2× 244 0.2× 2.1k 1.4× 878 0.6× 189 0.3× 179 5.8k
Christian Devaux France 44 916 0.6× 114 0.1× 438 0.3× 2.7k 2.0× 379 0.6× 184 7.4k
Dominic E. Dwyer Australia 48 1.0k 0.7× 214 0.1× 862 0.6× 4.0k 2.9× 1.3k 2.0× 309 9.6k
John A. Stewart United States 42 267 0.2× 181 0.1× 945 0.7× 966 0.7× 321 0.5× 156 5.6k

Countries citing papers authored by Christopher J. O’Callaghan

Since Specialization
Citations

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

Fields of papers citing papers by Christopher J. O’Callaghan

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Christopher J. O’Callaghan. 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 Christopher J. O’Callaghan. The network helps show where Christopher J. O’Callaghan may publish in the future.

Co-authorship network of co-authors of Christopher J. O’Callaghan

This figure shows the co-authorship network connecting the top 25 collaborators of Christopher J. O’Callaghan. A scholar is included among the top collaborators of Christopher J. O’Callaghan 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 Christopher J. O’Callaghan. Christopher J. O’Callaghan 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.
Kennecke, Hagen F., Christopher J. O’Callaghan, Dongsheng Tu, et al.. (2024). The NEO-RT trial: A phase 3 randomized trial of neoadjuvant chemotherapy, excision and observation versus chemoradiotherapy for early rectal cancer, CCTG CO.32.. Journal of Clinical Oncology. 42(16_suppl). TPS3646–TPS3646. 1 indexed citations
2.
Gupta, Arjun, Christopher J. O’Callaghan, Liting Zhu, et al.. (2024). The association of health-care contact days with physical function and survival in CCTG/AGITG CO.17. JNCI Journal of the National Cancer Institute. 116(8). 1313–1318. 7 indexed citations
3.
Titmuss, Emma, James T. Topham, David F. Schaeffer, et al.. (2024). Clonal hematopoiesis of indeterminate potential (CHIP), treatment outcomes and adverse events in gastrointestinal cancers: A pooled analysis of clinical trial and real-world data.. Journal of Clinical Oncology. 42(3_suppl). 169–169.
4.
5.
Chen, Nan, Dongsheng Tu, Stephanie Yasmin Brule, et al.. (2023). Predictive and prognostic features of metastatic colorectal cancer arising from the transverse colon: A pooled analysis of the CCTG/AGITG CO.17 and CO.20 randomized trials.. Journal of Clinical Oncology. 41(4_suppl). 124–124. 1 indexed citations
6.
Brandes, Alba A., J. Gregory Cairncross, Keyue Ding, et al.. (2020). Temozolomide and seizure outcomes in a randomized clinical trial of elderly glioblastoma patients. Journal of Neuro-Oncology. 149(1). 65–71. 17 indexed citations
7.
Hamilton, Robert J., Keyue Ding, Juanita Crook, et al.. (2020). The Association Between Statin Use and Outcomes in Patients Initiating Androgen Deprivation Therapy. European Urology. 79(4). 446–452. 27 indexed citations
8.
Berlowitz, David J., Marnie Graco, Rachel Schembri, et al.. (2018). Comparison of diurnal blood pressure and urine production between people with and without chronic spinal cord injury. Spinal Cord. 56(9). 847–855. 9 indexed citations
9.
10.
Ringash, Jolie, Heather‐Jane Au, Lillian L. Siu, et al.. (2013). Quality of life in patients with K‐RAS wild‐type colorectal cancer. Cancer. 120(2). 181–189. 12 indexed citations
11.
Ogden, N. H., M. Bigras-Poulin, Christopher J. O’Callaghan, et al.. (2006). Vector seasonality, host infection dynamics and fitness of pathogens transmitted by the tickIxodes scapularis. Parasitology. 134(2). 209–227. 90 indexed citations
12.
Ogden, N. H., Ian K. Barker, Guy Beauchamp, et al.. (2006). Investigation of Ground Level and Remote-Sensed Data for Habitat Classification and Prediction of Survival of <I>Ixodes scapularis</I> in Habitats of Southeastern Canada. Journal of Medical Entomology. 43(2). 403–414. 50 indexed citations
13.
Ogden, N. H., M. Bigras-Poulin, Christopher J. O’Callaghan, et al.. (2005). A dynamic population model to investigate effects of climate on geographic range and seasonality of the tick Ixodes scapularis. International Journal for Parasitology. 35(4). 375–389. 249 indexed citations
14.
O’Callaghan, Christopher J. & Fiona McDermott. (2004). Music Therapy's Relevance in a Cancer Hospital Researched Through a Constructivist Lens. Journal of Music Therapy. 41(2). 151–185. 41 indexed citations
15.
Heyland, Daren K., Graeme Rocker, Peter Dodek, et al.. (2002). Family satisfaction with care in the intensive care unit: Results of a multiple center study*. Critical Care Medicine. 30(7). 1413–1418. 345 indexed citations
16.
Peter, T., Brian D. Perry, Christopher J. O’Callaghan, et al.. (1998). Distributions of the vectors of heartwater, Amblyomma hebraeum and Amblyomma variegatum (Acari: Ixodidae), in Zimbabwe. Experimental and Applied Acarology. 22(12). 725–740. 27 indexed citations
17.
Edmunds, W. John, Graham F. Medley, D. James Nokes, et al.. (1996). Epidemiological patterns of hepatitis B virus (HBV) in highly endemic areasr. Epidemiology and Infection. 117(2). 313–325. 134 indexed citations
18.
O’Callaghan, Christopher J., Paddy A. Phillips, Henry Krum, & L. G. Howes. (1995). The effects of short-term alcohol intake on clinic and ambulatory blood pressure in normotensive ‘social’ drinkers. American Journal of Hypertension. 8(6). 572–577. 26 indexed citations
19.
O’Callaghan, Christopher J., William J. Louis, Graeme K. Hart, et al.. (1994). Rapidly Developing Pseudohypertension after Renal Transplantation Diagnosed by Non-Auscultated Blood Pressure Measurement. ˜The œNephron journals/Nephron journals. 67(1). 101–103. 2 indexed citations
20.
Conrad, P. A., Onesmo K. ole-MoiYoi, Cynthia L. Baldwin, et al.. (1989). Characterization of buffalo-derived theilerial parasites with monoclonal antibodies and DNA probes. Parasitology. 98(2). 179–188. 46 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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