Examining transcranial random noise stimulation as an add-on treatment for persistent symptoms in schizophrenia (STIM’Zo): a study protocol for a multicentre, double-blind, randomized sham-controlled clinical trial

Table 2 Participant timeline

	Baseline		Acute phase	Follow-up period
	V0	V1	Acute phase	V2	V3	V4	V5
	D-30 to D-7	D-7 to D0	D1 to D5	D5 to D10	D 35 ± 3	D 90 ± 7	D 180 ± 7
Screening eligibility, demography, medical and psychiatric^a history, treatment, pregnancy test^b	X
Written informed consent and enrolment		X
PANSS evaluation	X	X		X	X	X	X
Randomization^c			X (D1)
Drug toxicology screening and AP		X
Physical and clinical examination		X		X	X	X	X
hf-tRNS sessions^d			X
FTND		X			X		X
SNS		X			X	X
AHRS, HCS, PSAS, CDSS, CGI		X		X	X	X	X
MRI^e, SGI, source memory^f		X		X
Blood samples^g			X (D1)
FAR^h		X	X (D1)	X
SQoL-18		X					X
BNSS		X		X			X
MARS, BMQs, SUMD		X				X
Medication deviationⁱ, AE		X	X	X	X	X	X

^aLength of the episode, number of treatments, number of previous treatments, hospitalizations, symptom severity, disease duration—diagnostic of schizophrenia and the verification of the absence of comorbidities will be performed using the MINI 6.0
^bUrinary test
^cPatients will be randomly allocated to receive either active or sham hf-tRNS sessions
^dhf-tRNS sessions will be delivered twice a day separated by at least 2 h for 5 consecutive weekdays from D1 to D5 (Monday to Friday, 10 sessions)
^eMRI will include an anatomical MRI sequence, a resting-state fMRI sequence and DTI sequences; an optional perfusion ASL sequence will also be performed in two centres
^fSource memory task investigating patient’s capacity to distinguish between internally and externally generated words
^gCollection of 2 × 5 mL in vacutainers of blood between 8 and 9 am in fasting patients will be taken of the first hf-tRNS session (D1) for ancillary study 1
^hThe FAR test will be performed before the 1st session (V1 or D0 or D1 before the first session), between the 1st and the 2nd session of hf-tRNS (D1) and after the 10th session (V2) for ancillary study 2
ⁱThe medicinal antipsychotic treatments will remain stable for the full length of the study (D1 to D120). The patient will be withdrawn from the study if there is a need to adapt the dose or change the antipsychotic treatment (see exception)

ISSN: 1745-6215