ta in the present night,
where parameter <code>includenightcrit</code> is used to define how many
valid hours are need.</p></li>
<li><p>3: no accelerometer data available.</p></li>
<li><p>4: there are no nights to be analysed for this person.</p></li>
<li><p>5: SPT estimated based on guider only, because either no SIB was
found during the entire guider window which complicates defining the
start and end of the SPT, or the user specified the ID number of the
recording and the night number in the data_cleanin