Finding Clinical Trials

Searching efficiently for clinical trials is often challenging for researchers. The majority of clinical trials are not published in peer-review publications. Therefore, the results are never reported and disseminated (1). Additionally, there are multiple clinical trial registries with considerable overlap (2).

While the aim of the International Clinical Trials Registry Platform (ICTRP), launched in 2007 by the World Health Organisation (WHO) (3), is to act as a single platform to search for clinical trials, it has been reported by Glanville and Knelangen that “even though is included in the WHO ICTRP Search Portal, not all records can be successfully retrieved via searches of the ICTRP Search Portal”(4). To be comprehensive when searching for clinical trials, we will need to search across multiple registers.

Here are some steps that may be helpful when searching for clinical trials:

Finding clinical trials from registries:

Finding clinical trials with published results:

  • PubMed clinical queries
    A broad therapy search will retrieve clinical trials, if you are interested in Randomized Clinical trials only, you can change the scope from broad to specific/narrow.

  • The Cochrane Central Register of Controlled Trials (CENTRAL)
    The records are pulled mainly from the databases PubMed and Embase.

    In the advanced search, you can select “Studies with Results” to retrieve only studies where the results have been reported:

Finding clinical trials for COVID-19:

For information on clinical trials at MSKCC, please visit the following page:


  1. DeVito NJ, Bacon S and Goldacre B. Compliance with legal requirement to report clinical trial results on a cohort study. The Lancet 2020; 395: 361-369. DOI: 10.1016/S0140-6736(19)33220-9.
  2. van Valkenhoef G, Loane RF and Zarin DA. Previously unidentified duplicate registrations of clinical trials: an exploratory analysis of registry data worldwide. Systematic Reviews 2016; 5: 116. DOI: 10.1186/s13643-016-0283-8.
  3. Karam G and Ross AL. The WHO International Clinical Trials Registry Platform: Providing global clinical trial information to all. On Medicine. 2020.
  4. Lefebvre C GJ, Briscoe S, Littlewood A, Marshall C, Metzendorf M-I, Noel-Storr A, Rader T, Shokraneh F, Thomas J, Wieland LS. . Chapter 4: Searching for and selecting studies. In: Higgins JPT TJ, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (ed) Cochrane Handbook for Systematic Reviews of Interventions version 61 (updated September 2020). Cochrane, 2020.

Oncologic Hospital Readmissions

Cancer patients are at a higher risk of hospital readmissions than the general population. A recent study conducted by a team at the Boston University School of Medicine (Boston, MA) identified avoidable oncologic readmissions and their causes. The researchers conducted a retrospective chart review over a six-month period, during which 203 patients were discharged. While 68.7% of readmissions could not have been avoided, the authors found that 31.3% were potentially avoidable. Most of those potentially avoidable readmissions were due to ascitic or pleural fluid reaccumulation. Based on those findings, the researchers offer solutions such as performing supervised procedures in the outpatient setting. Addressing the issues could decrease readmissions in an oncology service. The study was published in JCO oncology practice.

Delaying Cancer Treatments and Impact on Mortality

In the unprecedented time of COVID-19, there is a dire need to understand the impact of delaying cancer treatment. A team from Canada and the United-Kingdom undertook a Systematic Review and Meta-Analysis of studies published from January 2000 to April 2020 to quantify the impact of delays in surgical interventions, systemic treatment (such as chemotherapy), or radiotherapy for seven types of cancer. These seven cancers represent “44% of all incident cancers globally”.

From analyzing studies included in the review, the authors concluded that every four-week delay in cancer treatment was associated with increased mortality. Delaying more than four weeks was associated with an even higher increase in the risk of death. For instance, delaying breast cancer surgery for eight weeks would increase the risk of death by 17%. This risk would be 26% with a twelve-week delay.

The study was published in November 2020 in the BMJ. The findings of this Systematic Review and Meta-Analysis will be instrumental in creating policies on cancer management priorities during a pandemic.

Hanna, T. P., King, W. D., Thibodeau, S., Jalink, M., Paulin, G. A., Harvey-Jones, E., O’Sullivan, D. E., Booth, C. M., Sullivan, R., & Aggarwal, A. (2020). Mortality due to cancer treatment delay: systematic review and meta-analysis. BMJ (Clinical research ed.), 371, m4087.