New research into methods to find out the effects of treatments: Why it matters

A new way of using UK Registry data

In traditional studies to look at treatment effects, new information is collected to find out the answers. Usually people are invited to take part in a clinical trial, and information about their health and symptoms are collected to find out how well a treatment works and if there are any safety concerns. But this may not always be possible, so what if researchers could use information that is already collected from people with CF, held in CF registries, to answer these types of questions too? 

We can do this using a research method called ‘trial emulation’, which statisticians and other health researchers have started to investigate in CF and across a wide range of other health conditions. As well as being able to answer new questions about effects of treatments that may not be available from traditional clinical trials, trial emulation studies may also be able to answer questions faster. With funding from the National Institute for Health and Care Research (NIHR) with additional support from the Trust, we have recently started a new study which will advance the methods for this approach, working with the community to understand how best to use UK CF Registry data for this purpose.

Getting answers to your questions

Target trial emulation has a huge potential to answer many important questions about the effects of treatments. 

For example, what are the long-term effects of medications in CF? This is a priority question for the CF community but difficult to answer in traditional studies as they typically only run for short periods of time, eg months rather than years. 

Another question that can be difficult to answer in traditional clinical trials is about the best treatment options for those not able to take CFTR modulators, because the total number of people able to join a clinical trial may be lower than needed to answer the question. 

Both questions could be addressed using UK CF Registry data and trial emulation. There are also many other questions from the CF community about the potential benefits and side effects from medications used in CF that could be tackled using this method, including some of the unanswered questions about treatments that were identified as priorities in the James Lind Alliance research priority refresh conducted with the CF community. 

How does trial emulation work?

Target trial emulation involves two steps:

1. Firstly, we plan an ideal – but imaginary – clinical trial that is designed to test a new treatment of interest. We plan what types of people would be eligible for the study, what treatments to test, what data we would collect on people and how long the trial would last. This imaginary trial is our ‘target trial’.
2. The second step is to think about how we can ‘emulate’ or ‘mimic’ the target trial using data that already exist in the UK CF Registry. We don’t need to go out and collect new information or recruit people to take part in a study, we instead use the data on the UK CF Registry that are already collected by CF teams. We find people in the registry who fit the criteria for our target trial and use their data on treatment use and health measures to estimate how well treatments are working. 

Ready, steady, bake…

Fans of the TV programme the Great British Bake Off may know that every day, before the contestants begin cooking, each of their ovens are tested. The production team of the show make a cake in each oven for the same length of time, to check that all the ovens are working in the same way.

This fun fact may help to explain the first steps of our study. Before we can begin answering new questions, we need to check that the method (or the oven in the Bake Off comparison) works. 

Room for improvement

We have already started using target trial emulation and UK CF Registry data to answer questions on the effects of medicines. However, we know that there are ways to improve how these new types of studies are done. We will compare different ways of applying this method to find out how to get the most reliable results.

This might also help to shape what information about treatments we collect on the Registry, and whether it may be useful to include more details on the different treatments that people are prescribed.

We need you! 

We are holding focus groups to inform and design this study and would love for the CF community to get involved. You can let us know if you’re interested by emailing [email protected].