title: California Verbal Learning Test-II performance in schizophrenia as a function of ascertainment strategy: comparing the first and second phases of the Consortium on the Genetics of Schizophrenia (COGS).
abstract: The first phase of the Consortium on the Genetics of Schizophrenia (COGS-1) showed performance deficits in learning and memory on the California Verbal Learning Test, Second Edition (CVLT-II) in individuals with schizophrenia (SZ), compared to healthy comparison subjects (HCS). A question is whether the COGS-1 study, which used a family study design (i.e. studying relatively intact families), yielded "milder" SZ phenotypes than those acquired subsequently in the COGS-2 case-control design that did not recruit unaffected family members. CVLT-II performance was compared for the COGS-1 and COGS-2 samples. Analyses focused on learning, recall and recognition variables, with age, gender and education as covariates. Analyses of COGS-2 data explored effects of additional covariates and moderating factors in CVLT-II performance. 324 SZ subjects and 510 HCS had complete CVLT-II and covariate data in COGS-1, while 1356 SZ and 1036 HCS had complete data in COGS-2. Except for recognition memory, analysis of covariance showed significantly worse performance in COGS-2 on all CVLT-II variables for SZ and HCS, and remained significant in the presence of the covariates. Performance in each of the 5 learning trials differed significantly. However, effect sizes comparing cases and controls were comparable across the two studies. COGS-2 analyses confirmed SZ performance deficits despite effects of multiple significant covariates and moderating factors. CVLT-II performance was worse in COGS-2 than in COGS-1 for both the SZ and the HCS in this large cohort, likely due to cohort effects. Demographically corrected data yield a consistent pattern of performance across the two studies in SZ.
authors.affiliation: Department of Psychiatry, Harvard Medical School, Boston, MA, United States; Massachusetts Mental Health Center Public Psychiatry Division of the Beth Israel Deaconess Medical Center, Boston, MA, United States. Electronic address: wstone@bidmc.harvard.edu.
authors.forename: William S
authors.initials: WS
authors.lastname: Stone
authors.affiliation: Department of Psychiatry, Harvard Medical School, Boston, MA, United States; Massachusetts Mental Health Center Public Psychiatry Division of the Beth Israel Deaconess Medical Center, Boston, MA, United States.
authors.forename: Raquelle I
authors.initials: RI
authors.lastname: Mesholam-Gately
authors.affiliation: Department of Psychiatry, University of California San Diego, La Jolla, CA, United States; VISN-22 Mental Illness, Research, Education and Clinical Center (MIRECC), VA San Diego Healthcare System, United States.
authors.forename: David L
authors.initials: DL
authors.lastname: Braff
authors.affiliation: Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Monica E
authors.initials: ME
authors.lastname: Calkins
authors.affiliation: Department of Psychiatry, University of Colorado Health Sciences Center, Denver, CO, United States.
authors.forename: Robert
authors.initials: R
authors.lastname: Freedman
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, United States; VA Greater Los Angeles Healthcare System, Los Angeles, CA, United States.
authors.forename: Michael F
authors.initials: MF
authors.lastname: Green
authors.affiliation: Department of Psychiatry, University of California San Diego, La Jolla, CA, United States.
authors.forename: Tiffany A
authors.initials: TA
authors.lastname: Greenwood
authors.affiliation: Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Raquel E
authors.initials: RE
authors.lastname: Gur
authors.affiliation: Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Ruben C
authors.initials: RC
authors.lastname: Gur
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, United States; Department of Pediatrics, Stanford University, Stanford, CA, United States.
authors.forename: Laura C
authors.initials: LC
authors.lastname: Lazzeroni
authors.affiliation: Department of Psychiatry, University of California San Diego, La Jolla, CA, United States; VISN-22 Mental Illness, Research, Education and Clinical Center (MIRECC), VA San Diego Healthcare System, United States.
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Light
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, United States.
authors.forename: Keith H
authors.initials: KH
authors.lastname: Nuechterlein
authors.affiliation: Department of Psychiatry, University of Colorado Health Sciences Center, Denver, CO, United States.
authors.forename: Ann
authors.initials: A
authors.lastname: Olincy
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, United States; VA Puget Sound Health Care System, Seattle, WA, United States.
authors.forename: Allen D
authors.initials: AD
authors.lastname: Radant
authors.affiliation: Department of Psychiatry, The Mount Sinai School of Medicine, New York, NY, United States; James J. Peters VA Medical Center, New York, NY, United States.
authors.forename: Larry J
authors.initials: LJ
authors.lastname: Siever
authors.affiliation: Department of Psychiatry, The Mount Sinai School of Medicine, New York, NY, United States; James J. Peters VA Medical Center, New York, NY, United States.
authors.forename: Jeremy M
authors.initials: JM
authors.lastname: Silverman
authors.affiliation: Department of Psychiatry, University of California San Diego, La Jolla, CA, United States.
authors.forename: Joyce
authors.initials: J
authors.lastname: Sprock
authors.affiliation: Department of Biostatistics, University of California Los Angeles School of Public Health, Los Angeles, CA, United States.
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Sugar
authors.affiliation: Department of Psychiatry, University of California San Diego, La Jolla, CA, United States.
authors.forename: Neal R
authors.initials: NR
authors.lastname: Swerdlow
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, United States; VA Puget Sound Health Care System, Seattle, WA, United States.
authors.forename: Debby W
authors.initials: DW
authors.lastname: Tsuang
authors.affiliation: Department of Psychiatry, University of California San Diego, La Jolla, CA, United States; Harvard Institute of Psychiatric Epidemiology and Genetics, Boston, MA, United States; VISN-22 Mental Illness, Research, Education and Clinical Center (MIRECC), VA San Diego Healthcare System, United States; Institute for Genomic Medicine, University of California San Diego, La Jolla, CA, United States.
authors.forename: Ming T
authors.initials: MT
authors.lastname: Tsuang
authors.affiliation: Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Bruce I
authors.initials: BI
authors.lastname: Turetsky
authors.affiliation: Department of Psychiatry, Harvard Medical School, Boston, MA, United States; Massachusetts Mental Health Center Public Psychiatry Division of the Beth Israel Deaconess Medical Center, Boston, MA, United States.
authors.forename: Larry J
authors.initials: LJ
authors.lastname: Seidman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002140:California; D016022:Case-Control Studies; D015331:Cohort Studies; D058068:Endophenotypes; D005190:Family; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects; D011939:Mental Recall / Q000187:drug effects; D008875:Middle Aged; D009483:Neuropsychological Tests; D021641:Recognition, Psychology / Q000187:drug effects; D012559:Schizophrenia / Q000150:complications / Q000188:drug therapy / Q000235:genetics / Q000503:physiopathology; D012565:Schizophrenic Psychology; D013067:Speech Perception / Q000187:drug effects; D014706:Verbal Learning / Q000187:drug effects; D055815:Young Adult
keywords: California Verbal Learning Test; Endophenotype; Memory; Schizophrenia; Verbal learning