Experiences with data from a Brazilian cohort
The Brazilian High-Risk Cohort Study (BHRCS) is a longitudinal dataset that has been following a cohort of children and adolescents for over 10 years with lots of value for mental health research. Cohort studies like it take time, effort, and people – now including you, Rodolfo. What has been your involvement in working with this cohort study so far?
I started working with the BHRCS in 2020 when I was invited to help plan the fourth wave of data collection, which started this year (2023). During this time, I also worked on a research project which involved analysing some of the previously collected data, which really helped me to better understand the full process of using it. Using the data in this way has been successful – currently, two of our articles are under review – and I am planning to continue to use it in future studies as well, as there are several research questions that can be well answered by the cohort.
While there are great benefits to using already collected data to answer research questions, there must also be some challenges. What would you say are the pros and cons of working with data from an established cohort?
Using already collected data has its issues and benefits. The main benefit, of course, is saving on resources. Cohort studies are expensive and need a large amount of work, including several different persons, to make them feasible. Researchers can save a lot of money by using data from established cohorts, like the BHRCS cohort, that have a free-of-cost nature and an open science process. Furthermore, it takes time to plan and establish a cohort, and after planning a cohort, there can be many years until data is actually collected and even more years to see the usefulness of the cohort. However, some issues include relying on other study teams to understand and work with the data. Whenever users are not familiar with the data not familiar with codes, it takes time to understand everything. Moreover, it is also very important to know what has been done with that data already, to avoid overlap. This part is quite difficult because it is sometimes not easy to find this research and previous materials when they were not well-documented.
It must be challenging then to take over from a cohort study previously led by others. Now that you are involved in collecting data, how have you found your transition from only using longitudinal data to also collecting it?
The planning of the 2023 data collection has put me on the other side of the bench, and this permitted me to understand the true difficulties of conducting a cohort, especially in a low- and middle-income country (LMIC).
First, several volunteers are needed, as the budget in LMICs is low, but a research career is very underpaid.
Second, infrastructure is needed to collect more sophisticated data; however, this is made more difficult by the lack of some infrastructure (e.g., magnetic resonance imaging (MRI)).
Third, the lack of staff causes an overburden of the main researchers.
Fourth, there is a lack of researchers, like post-graduate students, who end up using this data or helping in data collection – as the science career can be undervalued in LMICs (Low- and Middle-Income Countries) and as I mentioned earlier, underpaid.
However, even with all these problems, the BHRCS keeps a wonderful outcome as a children and adolescent cohort known and used worldwide. We are grateful for previous leaders, and currently two very altruistic and extremely hard-working leaders, Giovanni A. Salum and Pedro Mario Pan. I am very thankful for being able to use this already collected data, to collect more data and to offer it in an open-science framework. As someone who is both collecting and using data, I would like to encourage other large cohort studies to do as well.
It is great to hear that despite all the challenges, the BHRCS has been able to continue to collect and share data. It still has a lot to offer, so what advice would you give to a researcher considering using this or other longitudinal data from LMICs for their research project?
My advice is that those interested should become familiar with already published data from cohort studies like BHRCS, revise study protocols (BHRCS is available at https://osf.io/ktz5h/) and embrace the challenges and opportunities in working with data collected in an LMIC. Moreover, for those who want to collaborate with researchers already involved in LMIC cohorts, that could introduce a great opportunity to share knowledge and contribute to very important areas of research.