Clinical Applicability of the Test-retest Reliability of qEEG Coherence

  • Alycia M. Roberts Rainbow Babies & Children's Hospital
  • Paul Fillmore Baylor University
  • Scott L. Decker University of South Carolina
Keywords: qEEG, coherence, reliability, reliable change


Measurement reliability is an important aspect of establishing the utility of scores used in clinical practice. Although much is known about the reliability of quantitative electroencephalographic (qEEG) metrics related to absolute power, less is known about the reliability of coherence metrics. The current study examined the measurement reliability of coherence metrics across standard frequency bands during an eyes-closed resting state. Reliability was examined both within channel pairs, and averaged across spatially contiguous channels, to summarize global patterns. We found that while most channel pairs were highly reliable on average, there was substantial variability across channels. Finally, we estimated the effect of measurement reliability on the detection of treatment-related neural change. We concluded that estimates of reliability for treated channels are crucial, and should factor into clinical assessment of treatment efficacy for EEG biofeedback (neurofeedback), especially in cases where large cross-channel variability is present.

Author Biographies

Alycia M. Roberts, Rainbow Babies & Children's Hospital
Dr. Roberts is a postdoctoral fellow in pediatric neuropsychology in the Division of Developmental-Behavioral Pediatrics & Psychology.
Paul Fillmore, Baylor University
Dr. Fillmore is an Assistant Professor of Communication Sciences and Disorders
Scott L. Decker, University of South Carolina
Dr. Decker is an Associate Professor of School Psychology


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