Table 1B. Dopamine in medication-free schizophrenia patients with a first psychotic episode.

Study	Technique and ligand	Sample size	Main finding
Abi-Dargham et al.163	[11C]NNC 112 PET	16 SCZ of whom 7 FEP 16 HC	D1r bp DLPFC patients>HC
Abi-Dargham et al.164	[11C]NNC 112 PET	30 FEP 15 HC	DAT FEP<HC
Buchsbaum et al.165	(18)F-fallypride PET	15 FEP 15 HC	bp FEP<HC
Corripio et al.166	123I-IBZM SPECT	18 FEPa 12 HC	D2r bp FEP>HC
Corripio et al.167	123I-IBZM SPECT	37 FEPa 18 HC	D2r striatal/frontal ratios FEP>HC in those with SCZ
Glenthoj et al.168	123I-IBZM SPECT	25 FEP 20 HC	Extra striatal D2/D3 DAr bp FEP=HC
Graff-Guerrerro et al.169	[(11)C]-(+)-PHNO PET	13 FEPa 13 HC	Nondisplaceable D2/D3 bp FEP=HC
Graff-Guerrerro et al.170	[(11)C]-(+)-PHNO PET	13 FEPa 13 HC	D2/D3 bp FEP=HC
Hietala et al.171	[18F]-DOPA PET	7 FEP 8 HC	Striatal DA synthesis capacity FEP>HC
Hietala et al.172	[18F]-DOPA PET	10 FEP 10 HC	Striatal DA synthesis capacity FEP>HC
Hsiao et al.173	[99mTc]TRODAT SPECT	12 FEP 12 HC	DAT FEP=HC
Karlsson et al.174	[(11)C]SCH 23390 PET	10 FEP 10 HC	D1r bp FEP=HC
Laakso et al.175	[18F]CFT PET	9 FEP 9 HC	DAT FEP=HC
Lavalaye et al.176	[123I]FP-CIT SPECT	36 SCZ of whom 10 FEP 10 HC	DAT FEP=HC
Lehrer et al.177	(18)F-fallypride PET	33 SCZ of whom 14 FEP 18 HC	bp medial thalamus SCZ<HC (ES=0.89)
Lindstrom et al.178	[11C]-DOPA PET	12 SCZ of whom 10 FEP 10 HC	Striatal DA synthesis capacity FEP>HC
Mateos et al.179	[123I]FP-CIT SPECT	20 FEP 10 HC	DAT FEP<HC
Mateos et al.180	[123I]FP-CIT SPECT	30 FEP 15 HC	DAT FEP<HC
Mateos et al.181	[123I]FP-CIT SPECT	20 FEP 15 HC	DAT FEP<HC
Nozaki et al.182	[11C]-DOPA PET	18 SCZ of whom 14 FEP 10 HC	bp FEP>HC
Safont et al.183	(123)I-IBZM SPECT	37 FEPa 18 HC	D2r bp cannabis users=non-users
Schmitt et al.184	([99mTc]TRODAT-1 SPECT	10 FEP 10 HC	DAT FEP=HC
Schmitt et al.185	([99mTc]TRODAT-1 SPECT	28 FEP 12 HC	DAT FEP=HC
Schmitt et al.186	[99mTc]TRODAT-1 and [123I]IBZM SPECT	20 FEP 12 HC	DAT FEP=HC D2r bp FEP=HC
Schmitt et al.187	123I-IBZM SPECT	23 FEP 10 HC	D2r bp FEP<HC
Schmitt et al.188	[99mTc]TRODAT-1 and [123I]IBZM SPECT	12 FEP 12 HC	DAT FEP>HC D2r bp FEP=HC
Talvik et al.189	[11C]FLB 457 PET	9 FEP 8 HC	D2/D3 bp right thalamus FEP<HC,
Talvik et al.190	[(11)C]raclopride PET	18 FEP 17 HC	D2 bp right thalamus FEP<HC,
Yang et al.191	[99mTc]TRODAT SPECTand ([(123)I]IBZM) SPECT	11 FEP 12 HC	DAT FEP=HC D2/D3 bp FEP=HC
Yasuno et al.192	[(11)C]FLB 457 PET	10 FEP 19 HC	D2 bp FEP<HC thalamus

Abbreviations: bp, binding potential; D1r, dopamine D1 receptor; D2r, dopamine D2 receptor; DAT, striatal dopamine transporter; ES, effect size; FEP, first-episode psychosis; PET, positron emission tomography; SCZ, schizophrenia.

^aSamples overlap.