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Twelve recordings sample the SNUADC waveforms at 100 Hz

In 12 of 6,388 recordings every SNUADC waveform (ECG II, ECG V5, PLETH, and ART or CVP where present) is stored at 100 Hz instead of 500 Hz: case 299, case 803, case 1150, case 1693, case 2362, case 2920, case 4458, case 4582, case 5066, case 6119, case 6133 and case 6375.
Status established: shown on many cases, with a control.
Devices SNUADC
Variables ECG lead II (SNUADC), Plethysmogram (SNUADC), Arterial pressure (SNUADC)

What it means

Methods that assume 500 Hz (fiducial timing, the sawtooth fit, filters designed for 500 Hz) give wrong times or fail in these recordings; time resolution is 10 ms, not 2 ms. The conversion factors are the same as at 500 Hz.

What is done about it

Read the sample rate from each track's header rather than assuming 500 Hz; the PAT example and the census skip recordings without 500 Hz ECG and PLETH. Found by the signal survey.