What is a relaxed trial?

From the Guidelines

A relaxed trial is a clinical research study that allows for flexibility in its design and implementation, prioritizing external validity and generalizability to real-world settings over internal validity. This approach is particularly useful when studying interventions in diverse patient populations or under typical clinical conditions, rather than in highly controlled environments. The concept of relaxed trials is supported by recent studies, such as the one published in the Annals of Internal Medicine in 2020 1, which discusses the benefits of flexible trial designs in electronic health record-based interventions. According to this study, flexible trials can be more effective than traditional randomized controlled trials because they consider local context and variability in intervention design. Some of the key characteristics of relaxed trials include:

• Fewer exclusion criteria to allow for more diverse patient populations
• More flexible treatment approaches to reflect real-world clinical practice
• Simpler data collection methods and fewer mandatory follow-up visits
• Permission for adjustments to treatments based on patient response The use of relaxed trials can provide valuable insights into how interventions perform in everyday clinical practice, making them particularly useful for studying populations often excluded from conventional trials, such as elderly patients or those with multiple health conditions, as highlighted in a 2015 statement by the American Society of Clinical Oncology 1. Overall, relaxed trials offer a pragmatic approach to clinical research, prioritizing the evaluation of interventions in real-world settings to inform clinical decision-making and improve patient outcomes.

From the Research

Definition of a Relaxed Trial

There is no direct definition of a "relaxed trial" in the provided studies. However, the studies discuss the importance of inclusion and exclusion criteria in clinical trials and how they can affect the generalizability of the results.

Inclusion and Exclusion Criteria

• The studies suggest that strict inclusion and exclusion criteria can limit the number of eligible participants and affect the representation of certain patient populations 2, 3, 4.
• Common exclusion criteria include age, medical comorbidities, concomitant medication use, and female sex 2.
• The justification for exclusion criteria is not always strongly justified, and some studies have found that exclusion criteria are not always clearly reported 2.

Generalizability of Results

• The studies emphasize the importance of considering the generalizability of results when designing clinical trials 5, 2, 3, 6, 4.
• The use of strict inclusion and exclusion criteria can impair the generalizability of results, particularly for certain patient populations such as women, children, and the elderly 2, 4.
• The representation of under-served groups in clinical trials is crucial to improve the external validity of the findings 6.

Strategies to Improve Inclusion

• The studies suggest that a multi-faceted approach is essential to improve inclusion in clinical trials 6.
• Strategies such as cultural competency training, community partnerships, and personalized approaches can help increase inclusion 6.
• Increasing recruitment of staff from under-served groups and establishing a diverse community advisory panel can also help improve representation of under-served groups in clinical trials 6.