Boosting Brain Studies: Enhancements in Reliability with New Design Strategies

Brain-wide association studies, which link brain activity or structure to human behavior or health, typically struggle with replication issues. A recent study, published in *Nature*, underscores the importance of **thoughtful experimental design** to improve the reliability of these studies. Researchers analyzed over 77,000 brain scans from 63 different studies to determine factors that enhance study outcomes. One critical finding was that **strategically choosing study participants**—for instance, including individuals from a wide age range when studying age-related brain changes—yields more reliable results than random or narrow age sampling. The **study also revealed** that repeated brain scans of the same individual can either reinforce or compromise reliability, depending on the specific aspect being examined. By implementing these improved design strategies, future brain imaging studies could achieve reliable results with fewer participants. The study, spearheaded by Kaidi Kang, Simon Vandekar, and colleagues from multiple institutions in the U.S. and the U.K., offers **practical guidance** for researchers. Their work was supported by the National Institutes of Health.