A Review of Sleep EEG Patterns. Part I: A Compilation of Amended Rules for Their Visual Recognition according to Rechtschaffen and Kales Eine Ubersicht uber Schlaf-EEG-Muster. Teil I: Eine Zusammenstellung mit erganzenden Regeln zu deren visueller Analyse Task Force 'Scoring of Polysomnographic Recordings' of the German Sleep Society (DGSM):

Summary Question of the study The reliable evaluation of polysomnographic recordings (PSG) is an essential precondition for good clinical practice in sleep medicine. Although the scoring rules of Rechtschaffen and Kales [86] are internationally well established, they leave some room for different interpretations, and this may contribute to the limited reliability of visual sleep scoring. The German Sleep Society (DGSM) has set up a task force to devise ways to improve scoring reliability in the framework of their quality management programme. The intention was not to revise the rules of Rechtschaffen and Kales (R&K), but to facilitate their reliable application in sleep scoring and to support the development of standardized algorithms for computerized sleep analysis. Methods The task force was formed in September 2004 as a subcommittee of the educational panel of the DGSM. The members of the task force are experienced in sleep scoring and have a background either in physiology, neurology, psychiatry, psychology, or biology. The aim of the task force was to provide interpretation aids and, if needed, specifications or amendments to the R&K rules for the scoring of sleep electroencephalogram (EEG) waveforms and patterns. Decisions were based on the nominal group technique of a nominal panel as the formal consensus-building process. The consensus process was based on scoring and face-to-face discussions of at least 40 examples for each pattern in four 2-day meetings. Results Relevant EEG patterns for sleep stage scoring are alpha, theta, and delta waves, sleep spindles, K-complexes, vertex sharp waves, and sawtooth waves. If definitions for a given EEG pattern differed in the literature, the nominal group technique resulted in specifications and amended scoring rules for these EEG patterns. A second part including a series of examples with explanatory comments for each of these EEG patterns is under preparation.