Table 3. Time mark and period definitions used in the study.

Symbol	Definition
Time Mark	Time
collected during study
t1	Stimulus start
t2	Self-reported pain threshold reached
t3	Self-reported pain tolerance threshold (intolerable) or pain stimulus Safety limit reached/pain induction end
calculated after study
t0	30 seconds before t1
t1split	$\mathrm{t}1+\lfloor \frac{t2-t1}{2}\rfloor$ (floor function)
t2split	$\mathrm{t}2+\lfloor \frac{t2-t1}{2}\frac{t3-t2}{2}\rfloor$ (floor function)
Test period	Time limits
P0	[t0, t1)
P1	[t1, t1split]
P2	(t1split, t2)
P3	[t2, t2split]
P4	(t2split, t3]