Brain-wide association studies, which employ magnetic resonance imaging (MRI) to discern links between brain structure or functionality and human behavior or health, have often been criticized for yielding results that cannot be consistently reproduced by other researchers.

Recent research published in Nature, however, indicates that meticulous and careful study design can significantly enhance the reliability of findings in this field. This research was spearheaded by Kaidi Kang, a doctoral student in Biostatistics, Simon Vandekar, PhD, an associate professor of Biostatistics, and their team. The team scrutinized data from an extensive array of over 77,000 brain scans from 63 distinct studies.

The researchers discovered that studies could yield more reliable results by strategically selecting study participants to ensure a broader spectrum of the characteristics being examined. For instance, in a study focusing on age-related brain changes, incorporating participants from both younger and older age groups results in more dependable findings than those obtained from random sampling or focusing solely on middle-aged participants.

The study also unveiled that taking multiple brain scans from the same individual over time can enhance the reliability of certain brain measurements. However, for some measurements, this approach could actually decrease reliability, depending on the specific aspect being studied.

With these insights, the authors offer valuable guidance for scientists planning future brain imaging studies, potentially aiding them in achieving reliable results with fewer participants.

Kang and Vandekar’s team included investigators from six institutions based in the U.S. and the U.K. Other contributors from Vanderbilt include Jiangmei Xiong, MS, Megan Jones, Ran Tao, PhD, and Jonathan Schildcrout, PhD. The National Institutes of Health generously supported this study through various grants.