Table 2.
Detailed characteristics of cross-sectional studies (n = 34).
| Authors’ and publication year | Country | Research centre/Cohort | Participants | Assessment tool | Method of calculating score | Method of clustering | Number, label and distribution of clusters (n/%) | Significant correlates of clustersa |
|---|---|---|---|---|---|---|---|---|
| Positive symptoms | ||||||||
| Chang 201583 | Korea | Seoul National University Hospital and Boramae Medical Center | 111 patients with schizophrenia | LSHS-R | Sum score | Ward’s cluster analysis | Three: perception dimension and perception-cognition dimension (cluster 2 and 3) | Not reported. |
| Negative symptoms | ||||||||
| Strauss et al. 201385 | USA | Veterans Affairs Greater Los Angeles Healthcare System | 199 patients with schizophrenia | SANS | Mean factor scores (PCA) | Ward’s and K-means cluster analysis | Three: diminished expression (41/20.6), avolition–apathy (85/42.7) and low negative symptoms (75/37.7) | General psychopathology, severity of positive and negative symptoms, social anhedonia, attitude, global functioning, social cognition, hospitalization |
| Ahmed 201815 | USA | Maryland Psychiatric Research Center (MPRC) | 706 patients with chronic schizophrenia | SDS | Sum score | Latent class analysis with prior hypothesis | Three: deficit (128/19.3), persistent (174/25.1) and transient (404/55.6) | Sex, season of birth, ethnicity, years of education, illness onset, positive symptoms, neurocognitive performance, premorbid adjustment, psychosocial functioning |
| Positive and negative symptoms | ||||||||
| Trauelsen et al. 201669 | Denmark | OPUS | 97 patients with first-episode non-affective psychosis and 101 controls | PANSS | Z-scores | K-means cluster analysis | Four: low positive and negative symptoms (39/40.2), high positive and low negative (15/15.5), low positive and high negative (16/16.5), and high positive and high negative (24/24.7) | Metacognition |
| Talpalaru et al. 201977 | Multinational | North-western University Schizophrenia Data and Software Tool (NUSDAST) dataset | 104 patients with schizophrenia and 63 healthy controls | SAPS, SANS | Z-scores | Ward’s cluster analysis |
Three: high positive and negative symptom (27/26.0), predominantly positive symptom (36/34.6), and low symptom (41/39.4) |
Gender |
| Craddock 201821 | USA | National Institute of Mental Health (NIMH)/Childhood-onset schizophrenia (COS) cohort | 125 patients with childhood-onset schizophrenia (COS) | SAPS, SANS | Factor score (CFA) | K-means cluster analysis | Three: low positive and negative (37/29.6), high negative low positive (33/26.4), and high positive and negative (55/44.0) | IQ, global functioning, positive and negative symptoms |
| Cognitive deficits | ||||||||
| Dawes 201188 | USA | University of California/San Diego (UCSD) Advanced Center for Innovation in Services and Interventions Research (ACISIR) | 144 patients with schizophrenia or schizoaffective disorder | Comprehensive neuropsychological test battery (7 tests) | Sum of deviation scores adjusted to age, gender, education and ethnicity | Ward’s and K-means cluster analysis | Five: low visual learning and memory (19/13.2), low auditory and visual learning, memory and abstraction/cognitive flexibility (38/26.4), low abstraction/cognitive flexibility (40/27.8), low auditory learning, memory and abstraction/cognitive flexibility (17/11.8), and low visual learning, memory and abstraction/cognitive flexibility (30/20.8) | Educational status, ethnicity |
| Lewandowski 201887 | USA | McLean Hospital/Schizophrenia and Bipolar Disorder Program (SBDP) | 120 patients with psychosis and 31 healthy controls | MCCB (10 subtests) | Age and gender adjusted T-scores | Ward’s and K-means cluster analysis | Four: normal (39/32.5), mildly impaired (42/35.0), moderately impaired (18/15.0) and significantly impaired (21/17.5) | Educational status, premorbid IQ, state mania, positive and negative symptoms, antipsychotic dosage, cognition, community functioning |
| Reser et al. 201586 | Australia | Early Psychosis Prevention and Intervention Centre (EPPIC) | 128 patients with a first-episode psychosis | Comprehensive cognitive battery test (15 tests) | Range standardized test scores | Ward’s and K-means cluster analysis | Four: poor visual recognition memory (26/20.3), flat profile (46/35.9), strong performance (25/19.5) and poor performance (31/24.2) | Age, IQ (premorbid and current), years of education, negative symptoms, neurocognitive performance |
| Geisler 201575 | USA | Four research centers (MGH, UI, UMN, UNM)/Mind Clinical Imaging Consortium (MCIC) study of schizophrenia | 129 patients with schizophrenia and 165 healthy controls | Comprehensive neuropsychological test battery (18 tests) | PC score (PCA) | K-means cluster analysis | Four: diminished verbal fluency (38/29.4), diminished verbal memory and poor motor control (26/20.2), diminished face memory and slowed processing (21/16.3), and diminished intellectual function (44/34.1) | Duration of illness, positive symptoms, years of education, premorbid adjustment, cortical thickness, neural activity |
| Rangel et al. 201591 | Colombia | Universities of Antioquia, Pontificia Bolivariana, Nacional of Colombia | 253 patients with schizophrenia | Neuropsychological tests (5 tests) | Not reported | Latent classes analysis | Four: global cognitive deficit (74/29.2), memory and executive function deficit (75/29.6), memory and facial emotion recognition deficit (60/23.7), and without cognitive deficit (44/17.4) | Gender, age, negative symptoms, global functioning, employment status, adherence to treatment, neurocognitive performance, depression |
| Lewandowski 201418 | USA | McLean Hospital/Schizophrenia and Bipolar Disorder Program (SBDP) | 167 patients with psychosis | Neuropsychological battery test (5 tests) | Z-scores adjusted to age or age and education | Ward’s and K-means cluster analysis | Four: globally normal (46/27.5), normal processing speed/executive function (42/25.1), normal visuospatial function (35/21.0) and globally impaired (44/26.3) | Cognition, age, educational attainment, antipsychotics dosage, positive and negative symptoms, community functioning |
| Dickinson et al. 201992 | USA | National Institute of Mental Health Clinical Center | 540 schizophrenia patients, 247 unaffected siblings, and 844 control subjects | WRAT, WAIS IQ | Average of z-scores (based on controls mean and SD) | Two-step Cluster analysis | Three: cognitively stable (198/37), preadolescent impairment (105/19) and adolescent decline (237/44) | Polygenic risk scores (schizophrenia, cognition, education, ADHD), educational status, employment, positive and negative symptoms, global functioning, cognitive performance |
| Smucny et al. 201990 | USA | CNTRACS consortium | 223 psychosis patients and 73 healthy controls | Neuropsychological tests (3 tests) | Z-score and Factor score | Latent profile analysis (LPA) | Three: low (15/6.7), moderate (66/29.6) and high (142/63.7) | Negative, positive, disorganization, mania, and depressed mood symptoms, functioning, educational status, neurocognitive perfomance |
| Crouse et al. 201881 | Australia | Brain and Mind Research Institute | 135 patients with a psychosis-spectrum illness and 50 healthy controls | CANTAB (9 tests) | Age-adjusted Z-scores | Ward’s cluster analysis | Three: normal-range (46/34.0), mixed (58/43.0) and grossly impaired (31/23.0) | Socio-occupational functioning, neurocognitive performance, gender, diagnosis, risky drinking, employment status, educational status, premorbid IQ, negative symptoms |
| Sauve et al. 201838 | Canada | Douglas Mental Health University Institute (DMHUI)/ PEPP-Montreal program | 201 patients with psychosis on treatment and 125 healthy controls | CogState Schizophrenia Battery (13 tests) | Composite scores standardized to controls | Ward’s and K-means cluster analyses | Three: no impairment (169/51.8), generally impaired (39/12.0) and intermediately impaired (118/36.2) | IQ, severity of positive symptoms, age, years of education, stage of illness, antipsychotics dosage |
| Bechi 201893 | Italy | IRCCS San Raffael Scientific Institute | 452 patients with stable schizophrenia | BACS, WAIS-R | Mean score adjusted to age and education | Two-step cluster analysis (both scores together) | Three: high (135/29.9), medium (173/38.3) and low (144/31.8) (for all sample) | Age, years of education, age of onset, negative and positive symptoms, IQ, cognition |
| Uren et al. 201784 | Australia | Early Psychosis Prevention and Intervention Centre (EPPIC) | 133 patients with first episode psychosis and 46 controls | Comprehensive battery test (14 tests) | Z-scores | Ward’s and K-means cluster analysis | Three: severe global impairment (24/13.4), moderate impairment (73/40.8) and intact (82/45.8) | Age, premorbid IQ, positive and negative symptoms, cognitive performance, years of education, functioning |
| Ohi et al. 201753 | Japan | Kanazawa Medical University Hospital/ Kanazawa Medical University | 81 patients with schizophrenia, 20 relatives and 25 healthy controls | BACS (6 subscales) | Age- and gender-corrected raw scores | K-means cluster analysis | Three: neuropsychologically normal (36/28.6), intermediately impaired (60/47.6) and globally impaired (30/23.8) | Clinical diagnosis, neurocognitive performance, years of education, premorbid IQ, antipsychotics dosage |
| Prouteau et al. 201780 | France | Public psychiatric hospitals | 69 patients with schizophrenia spectrum disorders |
Objective: Neuropsychological tests (6 tests) Subjective: SSTICS |
Standardized Z-scores | Ward’s cluster analysis | Three: high cognitive impairment/moderate cognitive complaints (26/37.7), good cognitive functioning/moderate cognitive complaints (22/31.9) and moderate cognitive impairment/high cognitive complaints (21/30.4) | Age, educational status, negative symptoms, quality of life, anxiety, depression, stigma, neurocognitive performance |
| Rodrigez et al. 201779 | Czech | National Institute of Mental Health | 28 patients with first-episode SSD and 91 healthy controls | Neuropsychological battery tests (15 tests) | Z-scores standardized using controls | Ward’s cluster analysis | Three: generalized severe (10/35.7), partial mild (7/25.0) and near normal (11/39.3) | Neurocognitive performance |
| Rocca et al. 201694 | Italy | Multicentre study/Italian Network for Research on Psychoses (NIRP) | 809 patients with schizophrenia and 780 controls | MCCB (3 tests) | Z-scores of scales | Two-step cluster analysis | Three: unimpaired (340/42), impaired (408/50.4) and very impaired (61/7.5) | Age, educational status, cognitive performance, functioning, positive and negative symptoms, disorganization |
| Wells et al. 201595 | Australia | Australian Schizophrenia Research Bank (ASRB) | 534 patients with schizophrenia or schizoaffective disorder and 635 healthy controls | Neuropsychological tests (5 tests) | Z-scores standardized by healthy controls | Ward’s and K-means cluster analysis, and clinical method | Three: preserved (157/29), deteriorated (239/44) and compromised (138/26) | Age, years of education, age onset of illness, gender, neurocognitive performance, positive and negative symptoms, functioning |
| Gilbert 201482 | Canada | Institut en santé mentale de Québec | 112 patients with schizophrenia | Cognitive battery test (> 8 tests) | Average Z-scores | Ward’s cluster analysis | Three: generally impaired (18/16.1), selectively impaired (46/41.1) and near normal (48/42.8) | IQ, gender, socioeconomic status, cognition, antipsychotics dosage, global functioning, positive and negative symptoms |
| Quee et al. 201454 | Netherlands | Genetic Risk and Outcome of Psychosis (GROUP) | 654 health siblings of patients with schizophrenia | Neuropsychological battery test (8 tests) | Mean score of gender and age-adjusted z-scores | Ward’s and K-means cluster analysis | Three: normal (192/29.4), mixed (228/34.8) and impaired (234/35.8) | Age, educational status, IQ, premorbid adjustment, positive schizotypy |
| Ochoa et al. 201371 | Spain | Hospital and community psychiatric services | 62 patients with a first-episode psychosis | Neuropsychological battery tests (5 tests) | Demographically adjusted score | K-means cluster analysis | Three: higher neurodevelopment contribution (14/22.6), higher genetic contribution (30/48.4) and lower neurodevelopment contribution (18/29.0) | Neurocognition performance, premorbid IQ, neurological soft signs, premorbid adjustment, family history of mental disorders, obstetric complications |
| Bell 201076 | USA | Community mental health center (CMHC) | 151 patients with schizophrenia spectrum disorder (stable) | HVLT-R | Sum score | K-means cluster analysis (with prior hypothesis) | Three: nearly normal (52/34.4), subcortical (68/45.0) and cortical (31/20.5) | Educational status, neurocognitive performance, social cognition |
| Potter et al. 201070 | USA | University of Massachusetts | 73 patients with schizophrenia and 74 controls | Neuropsychological tests (6 tests) | Scaled scores | K-means cluster analysis | Three: intellectually compromised (31/42), intellectually deteriorated 21(/29) and intellectually preserved (21/29) | Negative symptoms, neurocognitive performance, educational status, general psychopathology |
| Wu et al. 201078 | Taiwan | Psychiatric rehabilitation hospital | 76 patients with schizophrenia | BNCE (10 subscales) | Mean scores | Ward’s cluster analysis | Three: near normal (34/45), deteriorated conceptual thinking (20/26), and anomia and impaired executive function (22/29) | Severity of negative symptoms |
| Bechi 201893 | Italy | IRCCS San Raffael Scientific Institute | 52 patients with stable schizophrenia | BACS, WAIS-R | Sum score | Two-step cluster analysis (both scores together) | Two: high (30/57.7) and medium (22/42.3) (subsamples with high pre-morbid IQ) | Age, years of education, age of onset, negative and positive symptoms, IQ, cognition |
| Negative symptoms and cognitive deficits | ||||||||
| Lysaker et al. 200974 | USA | Roudebush VA Medical Center and Community Mental Health Center (CMHC) | 99 patients with stable schizophrenia or schizoaffective disorder and on treatment | PANSS, CPT | Normalized z-scores | K-means cluster analysis | Four: low negative/relatively better attention (31/31.3), low negative/relatively poor attention (20/20.2), high negative/ relatively poor attention (28/28.3), and high negative/relatively better attention (20/20.2) | Self-esteem, attention performance, acceptance of stigma, severity of positive and negative symptoms, social functioning |
| Bell 201389 | USA | Community mental health center (CMHC) | 77 outpatients with stable schizophrenia or schizoaffective disorder | SANS, PANSS, MSCEIT | Sum score | Ward’s and K-means cluster analysis | Three: high negative symptom (24/31.2), low negative symptom with higher social cognition (27/35.1), and low negative symptom with poorer social cognition (26/33.7) | Quality of life, hospitalization, marital status, negative symptoms, social cognition |
| Schizotypy | ||||||||
| Lui et al. 201855 | China | Castle Peak Hospital | 194 unaffected first-degree relatives of patients with schizophrenia | CPPS (4 subscales) | Sum score | K-means cluster analysis | Four: high positive (33/17.0), high negative (66/34.0), mixed (27/13.9) and low (64/32.9) schizotypy | Positive and negative schizotypy, everyday life pleasure experiences, emotional expressivity |
| Wang et al. 201272 | China | Neuropsychology and Applied Cognitive Neuroscience Laboratory | 418 healthy college students | CPPS | Normalized component score (PCA) | K-means cluster analysis | Four: low (148/35.4), high positive (71/17.0), high negative (116/27.7), and mixed (high positive and negative) (83/19.9) schizotypy | Psychotic-like symptoms, depression, and social function, emotional expression, pleasure experiences, somatic symptoms, neurocognitive functioning, proneness to positive and negative symptoms |
| Barrantes-Vidal et al. 201073 | USA | University of North Carolina at Greensboro (UNCG) | 6,137 healthy college students | CPPS | Normalized component score (PCA) | K-means cluster analysis | Four: low (2,137/35), high positive (1,895/31), high negative (1,352/22), and mixed (high positive and negative) (753/12) schizotypy | Severity of positive and negative schizotypy, gender, social functioning, psychotic-like experiences, depression, substance use and abuse, schizoid and negative symptoms, personality, social adjustment |
| Chang 201583 | Korea | Seoul National University Hospital and Boramae Medical Center | 223 nonclinical population | LSHS-R | Sum score | Ward’s cluster analysis | Two: Perception dimension and Cognitive dimension | Not reported. |
BACS Brief Assessment of Cognition in Schizophrenia, BNCE Brief Neuropsychological Cognitive Examination, CANTAB Cambridge Neuropsychological Test Automated Battery, CPPS Chapman Psychosis Proneness Scales, CPT Continuous Performance Tests, HVLT-R Hopkins Verbal Learning Test—revised, LSHS-R Launay–Slade Hallucination Scale—revised, MCCB MATRICS Consensus Cognitive Battery, MSCEIT Mayer-Salovey-Caruso Emotional Intelligence Test, PANSS Positive and Negative Syndrome Scale, SANS Scale for the Assessment of Negative Symptoms, SAPS Scale for the Assessment of Positive Symptoms, SDS Schedule for the Deficit Syndrome, SSD Schizophrenia spectrum disorder, SSTICS Subjective Scale to Investigate Cognition in Schizophrenia, WAIS-R Wechsler Adult Intelligence Scale—revised, WRAT Wide-Range Achievement Test.
aResults from pairwise comparisons, univariable or multivariable logistic regression analyses.