Table 2.

Summary of variations in the Sensory Challenge Protocol (SCP) across the reviewed studies.

Author	Year	Sensory Challenge Protocol description	Presentation
Chang et al.	2012	Modification of the original SCP: (1) addition of standard tone at 84 dB; (2) siren at 78 dB	6 stimuli × 10 trials × 3 s at pseudorandom 12–17 s ISI
Lane et al.	2010	Modification of the original SCP: (1) used a classic steady tone at 78 dB; (2) fire engine at 84 dB	6 stimuli × 10 trials × 3 s at variable 10–17 s ISI
Mangeot et al.	2001	Used the original SCP	5 stimuli × 10 trials × 3 s at pseudorandom 15 or 19 s ISI × 20 s between sensory domains
McIntosh et al.	1999	Used the original SCP	5 stimuli × 10 trials × 3 s at pseudorandom 15 or 19 s ISI × 20 s between sensory domains
Miller et al.	2012	Used the original SCP	5 stimuli × 10 trials × 3 s at pseudorandom 15–19 s ISI × 20 s between sensory domains
Schaaf et al.	2003	Used the original SCP	5 stimuli × 10 trials × 3 s at pseudorandom 12–17 s ISI × 20 s between sensory domains
Schaaf et al.	2010	Modification of the original SCP: (1) addition of a tone at 84 dB; (2) siren at 78 dB; (3) 2-minute auditory tone at 75 dB	7 stimuli × 10 trials × 3 s at pseudorandom 12–17 s ISI × 20 s between sensory domains
Schaaf et al.	2015	Modification of the original SCP: (1) addition of a tone at 84 dB; (2) siren at 78 dB; (3) 2-minute auditory tone at 75 dB	7 stimuli × 10 trials × 3 s at pseudorandom 12–17 s ISI × 20 s between sensory domains
Schoen et al.	2009	Modification of the original SCP: (1) used a classic steady tone at 78 dB; (2) fire engine at 84 dB	6 stimuli × 10 trials × 3 s at variable 10–17 s ISI
Su et al.	2010	Used the original SCP	6 stimuli × 8 trials × 3 s at pseudorandom 12–17 s ISI

Note. ISI = interstimulus interval.