How Well Do Randomized Controlled Trials Reflect Standard Care: A Comparison between Scientific Research Data and...

Area of Science:

• Vascular Medicine
• Clinical Trials Methodology
• Rehabilitation Science

Background:

• Supervised exercise therapy (SET) is a cornerstone for managing intermittent claudication (IC).
• Randomized controlled trials (RCTs) are crucial for evaluating SET efficacy but may involve strict patient selection.
• Understanding selection bias in RCTs is vital for generalizability to real-world patient populations.

Purpose of the Study:

• To quantify patient selection in RCTs for intermittent claudication undergoing SET.
• To compare baseline characteristics and treatment response between RCT participants and standard care patients.
• To assess the impact of RCT eligibility criteria on reported treatment outcomes.

Main Methods:

• Systematic review of RCTs on SET for IC, extracting eligibility criteria.
• Comparison of baseline demographics, comorbidity, and walking capacity between RCT participants (n=1,440) and standard care patients (n=3,513).
• Analysis of differences in maximum walking distance improvement at 3 and 6 months, with ≥15% difference considered clinically relevant.

Main Results:

• All 20 included RCTs employed exclusion criteria, affecting large patient segments.
• Despite exclusions, baseline characteristics between RCT and standard care groups were largely comparable.
• Trial participants demonstrated statistically significant and clinically relevant lower improvements in maximum walking distance at 3 and 6 months compared to standard care patients.

Conclusions:

• RCT eligibility criteria for intermittent claudication may be implicitly applied in standard care referrals.
• The superior treatment response in standard care suggests that RCTs might underestimate the real-world benefits of supervised exercise therapy for IC.
• Further research should explore how to better represent diverse patient populations in clinical trials for IC.