Dr. John Davis Explains the Latest IQCB Guidelines

Introduction

As an area of health care specialization matures, it develops guidelines and standards so that service recipients can have greater trust that they will receive reliable and effective care. The International QEEG Certification Board (IQCB) has earlier created guidelines for specialty training and developed requirements for board certification in the practice of the quantitative EEG (qEEG). These are important steps to ensure good client care and recognition of the specialty by other health care practitioners and courts of law.

IQCB Guidelines for Quality Assurance

In 2025, the IQCB published guidelines for minimum technical requirements for performing clinical qEEGs (Collura et al., 2025). The guidelines extend the American Clinical Neurophysiological Society’s (ACNS) standards (Sinha et al., 2016) to detail requirements for acquiring multi-channel EEG data that can be subjected to qEEG analysis, adding requirements for selecting EEG segments, reporting, and analysis. These consensus recommendations were developed by IQCB members based on a systematic literature review and their knowledge of current practice issues.

The guidelines spell out steps required for gathering qEEG that will be useful for baseline assessment, planning training protocols, reporting, determining progress, forensic testimony, and supporting insurance claims. In addition, the guidelines will help support training and attaining and maintaining board certification in qEEG practice.

In addition, Collura et al. (2025) write that qEEG has clinical value as a supplement to conventional EEG in areas such as early detection of dysfunction, assessment of brain abnormalities, differential diagnosis, identifying abnormal background activity, prediction of treatment response, measurement of changes over time, and assessing treatment outcome. These functions all depend on the quality of EEG acquisition and the valid inspection, selection, and processing of the data. The guidelines define the following sequence of steps that are the necessary foundation for the practice of qEEG.

Acquisition

Using the 10-20 electrode placement system, EEG data should be gathered from 19 standard sites for at least 10 minutes in eyes-open (EO) and eyes-closed (EC) conditions with minimal amounts of artifact. Nevertheless, artifacts and drowsiness should be reported despite their removal before processing the data. Ten minutes of EO and EC data are usually enough for 2 to 5 minutes of artifact-free EEG to be available for qEEG analysis. However, a recording of up to 30 minutes may be necessary in extreme cases of hyperactivity or agitation so that 2 minutes of artifact-free data can be selected.

Visual Inspection

Before qEEG analysis, the entire EEG record should be reviewed by a professional who is qualified to identify medically-significant findings and artifacts so that they can be removed from the record. Qualification to do so is demonstrated by IQCB board certification or the equivalent. Visual inspection should be done with multiple montages (e.g., linked ears, longitudinal bipolar, transverse bipolar, average reference, or Laplacian). This helps to report the record's characteristics and select data of sufficient quality and quantity for the qEEG analysis.

The reviewer should be able to identify artifacts and significant normal variants and abnormalities to make referrals when the latter are suspected. Notable EEG activity to look for is detailed in the guideline (e.g., background rhythms, alpha blocking, asymmetries, epileptiform activity, etc.). Notable EEG findings can then be categorized as “rule out” (observation may be related to a significant disorder), “throw out” (artifacts), or “refer out” (findings that may be outside the scope of the reviewer and require a medical referral). The article suggests a possible outline for reporting on visual inspection:

1. Overall quality of the record

2. Amount of artifact

3. Amount of artifact-free recording

4. Background rhythm

5. Presence of drowsiness/sleep

6. Presence of paroxysmal disturbances

7. Comments (e.g., abnormalities and recommendations for clinical correlation)

Rejection of Artifact and Data Selection

The next step is to select artifact-free recording epochs for subsequent qEEG analysis. This may be done manually, by using an algorithm or template, or with principal component analysis (PCA), which removes data from all channels for the selected part of the record. Independent component analysis (ICA) can also be used with the caution that the subsequent qEEG analysis should be based on data samples that have been processed similarly. The ICA results should be compared to visual inspection findings.

Transients, normal or abnormal (e.g., frontal intermittent rhythmic delta, posterior slow waves of youth), should be retained for qEEG processing, whereas segments showing signs of drowsiness should be omitted. Data should be selected so that they do not include more than 10 segments of less than 1 second. When using automated artifacting methods, the results should be reviewed so that valid EEG activity is not omitted and that true artifacts are not missed. At least 1 minute of artifact-free recording should be obtained for qEEG analysis. However, 2 to 5 minutes is optimal to have a representative sample of the EEG consistent with the length of samples used in database construction.

Computation of Metrics

Spectral analysis for standard qEEG analysis should use fast Fourier transform (FFT) or the equivalent, where the epoch size determines the frequency sensitivity of the analysis (e.g., a 1-second epoch gives 1-Hz bins). Frequency bands should conform to published standards for recognized bands (e.g., delta, etc.), and amplifier matching should be applied when comparing systems. Metrics such as absolute power, relative power, and symmetry should be included in the form of tables and surface maps at a minimum. A qEEG database that is statistically reliable and valid and has been subjected to review for journal publication or by the Food and Drug Administration should be used. Also, the database should have considered factors such as demographics, drug and medication use, and diagnoses.

Other Considerations

Collura et al. (2025) also review the use of inverse solutions in qEEG analysis (e.g., versions of LORETA and VARETA) and issues related to ICA and PCA. When discussing discriminant function analysis and other classification algorithms, they suggest that these methods should not be used as a primary diagnostic screening tool due to excessively high false positive classification. Instead, discriminant functions should be used when a particular diagnosis is suspected.

Summary

The IQCB minimum requirements represent a significant step in the maturation of qEEG practice that will benefit the profession, and, more importantly, those who rely on qEEG findings to help address their clinical concerns. The authors provide three helpful tables to summarize their text, shown below.

Key Takeaways

Standardization is critical: The IQCB guidelines formalize data collection, inspection, and analysis procedures to improve qEEG reliability and clinical acceptance.
Artifact management is essential: Both manual and algorithmic methods must be used to exclude contaminants while preserving valid EEG signals.
Professional review is mandated: Only trained and certified reviewers should perform visual inspections and interpret findings.
qEEG is a complement, not a replacement: It supports conventional EEG in diagnosis, treatment monitoring, and forensic evaluation.
Data quality determines outcome: The clinical utility of qEEG is contingent upon rigorous acquisition and pre-processing standards.

Glossary

acquisition: the process of recording EEG using standardized electrode placement and conditions to ensure reliable data for qEEG analysis.

artifact: any unwanted signal in the EEG data not generated by brain activity, such as muscle movements or eye blinks.

discriminant function: a statistical method used to distinguish between diagnostic groups using multivariate EEG features.

eyes-closed (EC): a condition during EEG acquisition where the subject keeps their eyes closed, often increasing alpha activity.

eyes-open (EO): a condition during EEG acquisition with eyes open, used to contrast against EC recordings.

fast Fourier transform (FFT): a mathematical algorithm used to decompose the EEG signal into its constituent frequency components. It converts time-domain EEG data into a frequency-domain representation, allowing the quantification of spectral power within defined frequency bands (e.g., delta, theta, alpha). The result facilitates comparisons to normative databases and the generation of metrics such as absolute power, relative power, and coherence. FFT underpins standard qEEG analysis by enabling objective assessment of oscillatory brain activity.

independent component analysis (ICA): a computational technique that separates EEG into source components to identify and remove artifacts.

International QEEG Certification Board (IQCB): the certifying authority responsible for setting training standards, examination procedures, and practice guidelines for professionals using quantitative EEG clinically. It publishes consensus-based technical and procedural guidelines, such as the 2025 minimum requirements for clinical qEEG, to ensure quality assurance, professional competence, and recognition of qEEG within broader healthcare and legal contexts.

LORETA (low resolution electromagnetic tomography): a source localization algorithm that estimates the three-dimensional intracerebral electrical sources responsible for the EEG signals recorded at the scalp. It computes current source density (CSD) distributions across cortical voxels using a smoothness constraint that favors neighboring neuronal sources having similar activity. LORETA allows for functional brain mapping by estimating deep cortical generators of scalp-recorded potentials

principal component analysis (PCA): a statistical method to reduce data dimensionality and remove segments contaminated with artifacts.

qEEG (quantitative EEG): the mathematical and statistical analysis of EEG data to extract metrics for clinical interpretation.

transients: brief, non-rhythmic events in the electrical brain signal that typically last less than one second and differ markedly from the ongoing background activity. They can be normal (e.g., vertex waves, K-complexes, posterior slow waves of youth) or abnormal (e.g., epileptiform discharges, frontal intermittent rhythmic delta activity [FIRDA]).

VARETA (variable resolution electromagnetic tomography): an advanced source localization technique that extends LORETA by incorporating statistical priors and spatial resolution variability to improve the accuracy of source estimates. It adjusts spatial resolution depending on signal characteristics, enhancing the localization of both focal and distributed sources. VARETA is particularly suited for detecting subtle, distributed abnormalities in clinical populations.

visual inspection: manual evaluation of the raw EEG by a certified expert to assess data quality, identify abnormalities, and determine usability for qEEG.

Reference

Collura, T., Cantor, D., Chartier, D., Crago, R., Hartzoge, A., Hurd, M., Kerson, C., Lubar, J., Nash, J., Prichep, L. S., Surmeli, T., Thompson, T., Tracy, M., & Turner, R. (2025). International QEEG Certification Board guideline minimum technical requirements for performing clinical quantitative electroencephalography. Clinical EEG and Neuroscience, 15500594241308654. Advance online publication. https://doi.org/10.1177/15500594241308654

About the Author

Dr. John Raymond Davis is an adjunct lecturer in the Department of Psychiatry and Behavioural Neurosciences at McMaster University's Faculty of Health Sciences. His scholarly contributions include research on EEG changes in major depression and case studies on neurological conditions.

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