Human precision of operating a digitizing board: implications for electrocardiogram measurements

Area of Science:

• Medical instrumentation
• Human factors engineering
• Biomedical signal processing

Background:

• Accurate measurement is crucial in medical diagnostics and research.
• Digitizing boards are used for manual measurements from medical images and signals.
• Understanding human operator precision is essential for reliable data acquisition.

Purpose of the Study:

• To quantify the precision of human measurements made with a digitizing board.
• To evaluate errors in repeated distance and point localization tasks.
• To assess the impact of digitizing board use on simulated electrocardiogram (ECG) measurements.

Main Methods:

• 100 healthy volunteers performed repeated measurements on an artificial pattern using a high-precision digitizing board.
• Errors in repeated distance measurement and point relocalization were recorded.
• Simulated QT dispersion measurements were performed to assess practical application accuracy.

Main Results:

• Median errors for repeated distance measurements were 0.2 mm (mean) and 1.0 mm (maximum).
• Simulating QT dispersion measurement yielded a median error of 20 ms at a paper speed of 25 mm/s.
• The study demonstrated considerable variability and inaccuracy in human operation of digitizing boards.

Conclusions:

• Human precision in operating digitizing boards is significantly limited.
• Current methods may introduce substantial errors in medical measurements.
• Recommendations include using computer screens for ECG measurements or implementing real-time operator feedback systems to mitigate errors.