Table 1.

Studies comparing patients with schizophrenia or schizoaffective disorders and normal controls for the performance at the Iowa Gambling Task (IGT)

Authors	Subjects	Assessments	Results	Comments
Studies showing differences in IGT performance between groups
Beninger et al. (2003)	36 patients (half on typical (67% male; age: 46 (mean)± 1 (SD)) and half (67% male; age 42±12) on atypical anti-psychotics) and 18 controls (67% male; age: 45±3). Exclusion of patients with substance abuse in the past month.	IGT (real card version), MMSE, BPRS, WCST, declarative memory questionnaire	IGT: patients on atypicals had fewer choices from advantageous decks compared to patients on typicals or controls a. Patient groups differ from controls for declarative memory and MMSE. Patients on typicals perform worse at the WCST than patients on atypicals and controls	No information about substance use disorders in controls. No information about past history of substance use disorders in patients
Ritter et al. (2004)	20 chronic patients (100% male, age: 48±6) and 15 controls (100% male, age: 47±10). Exclusion of subjects with substance use disorders for the past 3 months	IGT (computerized version) North American Adult Reading Test, WCST, BPRS, SANS	IGT: Patients had a larger differential between disadvantageous and advantageous cards and lost more money than controls. There were no differences between groups across blocks a. A history of alcohol use disorder as a covariate did not change results. Both groups perform poorly at the WCST.	No correlations between IGT variables and WCST or symptoms.
Shurman et al. (2005)	39 patients (72% male, age: 33±10) and 10 controls (50% male, age: 32±4). Exclusion of subjects with a history of substance use disorders	IGT (computerized version) WCST, DMST, PANSS, SANS, SAPS	IGT: Patients had smaller total net scores and earned less money than controls. Group differences for IGT performance across blocks a was significant at p=0.08. Patients had a preference for decks with low frequency and high punishments. Patients had worse WCST and DMST performances than controls. Total money amount earned at IGT was negatively correlated with SANS score.
Kester et al. (2006)	15 adolescents with schizophrenia (60% male, age: 16±3) and 25 controls (56% male, age: 17±2). Exclusion of subjects with substance use disorders	IGT (computerized version), WRAT-3, BPRS, SANS, PAS, GAS, and WCST	Patients are doing worse than controls for IGTa and WCST
Studies showing no differences in IGT performance between groups
Wilder et al. (1998)	12 patients (91% male, age: 33±6) and 30 controls (41% male; age: 30±10). Exclusion of subjects with substance use disorders for the past 6 months b	IGT (real card version) b, CVLT, LNSP, WCST WAIS-R, and WRAT-R reading test	No differences between groups for number of choices made from each deck and overall money lost at the IGT. Patients had a preference for decks with low frequency and high magnitude punishments. No correlations between IGT and cognitive variables	No analysis of substance use disorder data
Cavallaro et al. (2003)	110 patients with chronic schizophrenia (60% male; age: 33±9), 67 patients with OCDc (49% male; age: 30±9) and 56 controls (40% male; age: 31±6). Exclusion of patients with “multiple diagnoses”	IGT (real card version), WCST (real card version), Tower of Hanoi	Number of choices for disadvantageous decks did not differ between schizophrenia and control. Schizophrenia performed worse at the WCST and tower of Hanoi compared of controls	Unclear if subjects with substance use disorders were excluded from the study
Evans et al. (2005)	19 patients (gender not reported; age: 38±10) and 19 controls case-matched for age and level of education	IGT (real card version) WCST, COWAT, SANS, SAPS	No differences between groups for IGT performance and subjective experience across blocks a. Correlation between behavioral performance and subjective ratings No correlations between IGT outcomes and severity of symptoms	No information on substance use disorders. No comparison of groups for WCST and COWAT performances
Rodríguez-Sánchez et al. (2005)	80 first-episode (FE) patients (69% male, age: 26±7) and 22 controls 55% male, age: 26±6). Exclusion of patients with substance dependence	IGT (computerized version) WAIS-III backward digits, FAS, TMT, SANS, SAPS	No differences between groups for IGT (net scores, total net score, choices per Deck). Patients had worse cognition than controls	No information on history of substance abuse in patients
Thurnbull et al. (2006) d	21 chronic patients (61% male, age: 13±1) and 21 controls matched for age and education. No exclusion of substance use disorders	IGT (real card version), COWAT, WCST, tests of set-shifting abilities, SANS, SAPS	No differences between groups for IGTa. High levels of negative symptoms were associated with difficulties of reversal contingencies	No information on substance use disorders. Not specified if same sample as Evans et al. (2005)

CVLT = California Verbal Learning Test; WCST = Wisconsin Card Sorting Test; LNSP = Letter Number Span; WAIS-R = Wechsler Adult Intelligence Scale—Revised; WRAT-3 = Wide Range Achievement Test—Third Edition; BPRS = Brief Psychiatric Rating Scale; SANS = Scale for the Assessment of Negative Symptoms; DMST = Delayed match to Sample Task; PANSS = Positive and Negative Syndrome Scale; SAPS = Scale for the Assessment of Positive Symptoms; FAS = verbal fluency test; TMT = Trail Making Test; COWAT = Controlled Oral Word Association; PAS = Premorbid Adjustment Scale; GAS = Global Assessment Scale.

^aTwo-way analysis of variance (ANOVA; groups by net scores interaction effects).

^bPersonal communication from Dr. T. Goldberg.

^cResults for OCD patients are not reviewed.

^dIncludes same patients as Evans et al. (2005).