Searching clinical trials registers: guide for systematic reviewers
BMJ 2022; 377 doi: https://doi.org/10.1136/bmj-2021-068791 (Published 26 April 2022) Cite this as: BMJ 2022;377:e068791Linked Opinion
Untapping the hidden value of clinical trial registries
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Dear Editor
One of the great developments in mankind's history took place in 1995 when system engineers created the scripts language, which with the help of HTML – Hypertext Markup Language – made the work with computers an interactive pleasant process, which has changed our everyday life’s format. That change has been so great that we can say human civilization has taken a new great leap in its evolution.
We live all the time connected to a mobile cell phone, to a palm or lap-top, to a smart phone, to a Tablet, or to a portable computer. Every day it’s more difficult for us to withdraw from those devices connected to the Internet. Many things that we used to do routinely, every day, we now do them digitally, electronically. Nowadays new technologies occupy a relevant position, they are indispensable, in practically all of our daily social, academic, cultural, economic activities… Billions of people live connected to the Internet through different ypes of the above mentioned electronic devices, doing many things.
To inform and communicate, since the end of the 19th century we have gone from the use of telegraph, radio, telephone, black and white television, then color one, satellites, local networks, to the use of new electronic devices such as cell phones, email, messenger browsers and other new specialized systems. Social networks, blogs, wikis allow us to know a lot of hidden information, which is not formally published. With the use of electronic resources, libraries initially became discotheques and now are video libraries, websitetheques.
New information systems have appeared in medicine, big databases, which are changing the way doctors interact with their patients. In evidence-based medicine, the use of systematic reviews and meta-analyses has become widespread. These things made health professionals' activity, in practice, start to change. For instance, previously, the doctor's decision-making was based mainly on previous results obtained by him, as personal experience, in practice with patients, or on information provided, often in written form as narrative reviews, made by professional experts in a specific area. The value of those methodologies were untrustworthy and very limited. No doctor has enough experience to orient himself correctly from that subjective information, especially in an environment where clinical situations are not similar and very varied. Many times results were not as the doctor expected and very serious problems were generated by bad decisions in patients and in health care units; also complications and great economic losses arose.
The current methodology used allows the obtaining of information that should be objective and not the one that doctor subjectively constructs. For this reason, it is very important to use scientifically valued resources, by methods of evidence-based medicine, truthful, without bias to make correct and reasonable logical decisions that help solve health problems.
The paper by Drs. Hunter, Webster, Page, and others and published in The BMJ in April 2022 (1) is a wonderful step by step guide, with well selected cases, and excellent recommendations for conducting systematic search for studies using registers. Rofecoxib is an excellent example of emerging problems related to using traditional medical practices. At first sight, it seems to be a complex guide, time consuming, possibly because authors do not mention the main role playing by those above mentioned new electronic resources in management of scientific and technologic information and communication. Not only clinical trials registers are needed but also the use of other electronic tools for text mining, such as those offered by the powerful R software and its special packages (2), koRpus, quanteda, RWeka, Spacyr, Stringer, text2vec, tm, world cloud…
1 Kylie E Hunter, Angela C Webster, Matthew J Page…BMJ 2022; 377: e068791- Searching clinical trials registers: guide for systematic reviewers.
2.The R Project for Statistical Computing. https://www.r-project.org/about.html
Competing interests: No competing interests
Response to Dr Ledesma: automation tools
Dear Editor,
I would like to thank Dr Ledesma for his comments on 27 April regarding technological developments in searching and screening.
While developing the guidance paper (1), our author team discussed the availability of automation tools to improve efficiency of searching clinical trials registers. To our knowledge, most tools to date have been designed and applied to aid searches and screening for large bibliographic databases of published studies, such as Medline. Many of these have been compiled in a useful resource, known as The Systematic Review Accelerator (https://sr-accelerator.com/) (2). For instance, the Polyglot Search Translator (3) automatically translates search strings into strategies for multiple databases, and Screenatron streamlines title and abstract screening for structured bibliographic records. Similar innovations that are adapted to improve register searches and screening would be most welcome. These would need to consider the differing search interfaces and record formats across the 18 registers that provide data to the WHO ICTRP Search Portal (https://trialsearch.who.int/Default.aspx).
1. Hunter KE, Webster AC, Page MJ, et al. Searching clinical trials registers: guide for systematic reviewers BMJ 2022; 377 :e068791 doi:10.1136/bmj-2021-068791
2. Clark J, Glasziou P, Del Mar C, Bannach-Brown A, Stehlik P, Scott AM. (2020). A full systematic review was completed in 2 weeks using automation tools: a case study. J Clin Epidemiol. 2020 Jan 28;121:81-90. doi: 10.1016/j.jclinepi.2020.01.008
3. Clark JM, Sanders S, Carter M, et al. Improving the translation of search strategies using the Polyglot Search Translator: a randomized controlled trial. J Med Libr Assoc. 2020;108(2):195–207. doi:10.5195/jmla.2020.834
Competing interests: Competing interests have not changed since publication of the original article.