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For clinical use the NeuroGuide Analysis system is to be used by qualified medical and qualified clinical professionals for the post-hoc statistical evaluation of the human electroencephalogram (EEG).

The NeuroGuide Analysis System (NAS) is a software program for the post-hoc statistical analysis of the human electroencephalogram (EEG). EEG recorded on a separate device (i.e., the host system) is transferred to the NAS for display and user-review. The system requires that the user select reliable samples of artifact-free, eyes-closed or eyes open, resting digital EEG for purposes of analysis. Analysis consists of the Fast-Fourier Transformation (FFT) of the data to extract the spectral power for each of the four primary frequency bands (delta, theta, alpha, and beta), and frequency information from the EEG. The results of this analysis are then subjected to univariate, bivariate, and multivariate statistical analyses and displayed in statistical tables and topographical brain maps of absolute and relative power, power asymmetry, and coherence for 19 monopolar and 171 selected bipolar derivations of the EEG. In all over 1,200 measures are derived for comparison against a carefully constructed and statistically controlled age-regressed, normative database in which the variables have been transformed and confirmed for their Gaussian distribution. Each variable extracted by the analysis is compared to the database using parametric statistical procedures that express the differences between the patient and an appropriate age-matched reference group in the form of Z-scores. Multivariate features are compared to the normative database using Gaussian Univariate and Multivariate Distance Statistics. The Gaussian multivariate Distance statistic controls for the interrelationship of the measures of brain cortical function in the feature set, and provides an accurate estimate of their difference from normal. The multivariate measures permit an evaluation of regional indices of brain function that reflect the perfusion fields of the brain. Extracted feature sets are further analyzed to determine if the pattern of 'hits' (statistically significant feature score values identified for the patient) are consistent with patterns of 'hits' identified in prior neuroguide evaluations of clinical patients with known disorders. A step-wise discriminate analysis program classifies the patient in terms of their similarity to known neuroguide-defined patterns of abnormality, providing a probability estimate of the patient's profile with the average profile of groups of individuals constituting the normative and clinical database. The discriminant classification program is restricted by confining potential outcomes to specific patient symptoms derived from the patient history profile. Established discriminant functions were evaluated through the use of Receiver Operating Characteristic (ROC) curves for their sensitivity and specificity. The outcome of the statistical analysis is presented in report form that includes (a) patient demographic and history information, (b) selected EEG epochs, (c) statistical tables of monopolar, bipolar, and multivariate extracted feature values, and topographical brain mans. This information is to be read and interpreted within the context of the current clinical assessment of the patient by the attending physician/clinician. The decision to accept or reject the results of the neuroguide analysis, and incorporate these results into their clinical appraisal of the patient, is dependent upon the judgment of the attending physician or clinician.