Measurement precision and validity of the diagnostic interpretation are to a major extent associated with the noise interference in routinely recorded electrocardiograms (ECGs). In order to provide appropriate quality in the population-based KORA-F4 study, we applied a multi stage monitoring of the resting ECG recording including a comprehensive training of the technicians to enhance their skills for appropriate electrode application, artefact recognition and prevention, and in addition, computerized measurement of the noise superimposing the ECG. ECGs of predominantly good quality were obtained from 98.3% (3028/3080) of the study participants. The quality achieved is a precondition for reliable estimates of population-based ECG characteristics, especially when valid phenotyping for serial ECG analyses and genetic association studies is required.