After a stroke, which occurs when blood flow to the brain is disrupted, many people experience difficulty with movement. This research sought to understand and compare the scientific studies that investigate therapies for movement problems in the legs and feet following a stroke. Specifically, it looked at differences in these studies based on the economic resources of the country where the research was conducted.

The analysis focused on a specific type of high-quality study called a Randomized Controlled Trial (RCT). In an RCT, participants are randomly assigned to different groups to compare the effects of a new therapy against a standard one or no treatment. This method is a reliable way to determine if a therapy is effective. The researchers compared RCTs from High-Income Countries (HICs), which are wealthier nations, with those from Low-to-Middle-Income Countries (LMICs).

By conducting a thorough search of medical research databases up to December 2024, a total of 1,577 relevant RCTs were identified. The findings showed that the number of these studies conducted in LMICs has risen sharply since 2014. Since 2022, LMICs have produced more of these trials each year than HICs.

One key difference was the stage of stroke recovery being studied. Researchers in HICs were more likely to study individuals in the "chronic phase" of recovery, which is the long-term period several months after a stroke when recovery has often slowed down. The finding that this difference is unlikely due to random chance is supported by a statistical measure known as a p-value.

The types of therapies investigated also differed between the two groups of countries. Studies in HICs were more likely to examine therapies such as:

• Robotic training: Using robotic devices to assist with leg movements.
• Gait training: Physical therapy focused on improving a person's ability to walk.
• Treadmill training: Using a treadmill as part of walking therapy.
• Feedback training: Using technology to give a person real-time information about their movements to help them improve.
• Rhythmic-auditory training: Using sounds or musical beats to help guide movement.

In contrast, studies in LMICs were more likely to investigate:

• Acupuncture: A traditional therapy involving the insertion of thin needles into the skin.
• Task-specific training: Practicing real-life activities, like climbing stairs or getting out of a chair.
• Neurodevelopmental techniques: Hands-on therapy approaches aimed at improving movement patterns.
• Mirror therapy: Using a mirror to create a visual illusion of the affected leg moving correctly, which can help retrain the brain.

Another finding related to where the research was published. Scientific studies are published in academic journals, and a journal's influence is sometimes measured by its "impact factor." A higher impact factor generally suggests a journal is more widely read and cited by other scientists. A larger percentage of studies from HICs (28%) were published in journals with a higher impact factor (greater than 3) compared to studies from LMICs (18.4%).

This difference in publication venue occurred even though the studies from LMICs were found to be of similar quality and included more participants, which can make study results more reliable.

In summary, the yearly number of leg-rehabilitation trials for stroke recovery in LMICs has now surpassed that of HICs. Despite having similar quality, studies from LMICs are more often published in journals with a lower measured influence. The types of therapies studied in both settings were similar, which challenges a common assumption that research in LMICs would focus only on less expensive treatments.