Most neuroimaging studies have too few participants to reliably link complex behaviors to variations in brain structure or function, according to a study published March 16 in Nature. The results point to the importance of large, multisite collaborations and data-sharing to ensure that imaging studies have enough statistical power to detect real associations, the researchers say.
The median sample size for neuroimaging studies hovers at about 23 participants, the team reported, based on a survey of open-source imaging data. Studies of this size can occasionally associate brain scans and behavior by chance, but the findings vary across datasets. To yield reproducible data requires thousands of participants, the researchers found.
The analysis may explain why the field of neuroimaging has not progressed in understanding these types of correlations as quickly as some had hoped, the team says.
“We in the neuroimaging literature have labored for decades under the misguided assumption that ...
