Table 1.
Detailed characteristics of longitudinal studies (n = 19).
| Authors’ and publication year | Country | Research centre/Cohort | Participants | Assessment tool | Frequency of assessment | Duration of follow-up | Method of calculating test score | Method of trajectory analysis | Number, label and distribution (n/%) of trajectories | Significant predictors of trajectoriesa |
|---|---|---|---|---|---|---|---|---|---|---|
| Positive symptoms | ||||||||||
| Austin 201519 | Denmark | Centre for psychiatric research/OPUS trial trail | 496 patients with first-episode SSD and <3 months of treatment | SAPS | Five times | 10 years | Composite score using global scores | Latent class analysis | Five: response (233/47), delayed response (60/12), relapse (75/15), non-response (64/13) and episodic response (64/13) | Duration of untreated psychosis, global functioning, diagnosis and substance abuse |
| Pelayo-Terán et al. 201465 | Spain | University Hospital Marqués de Valdecilla/Clinical Programme on First‐Episode Psychosis of Cantabria (PAFIP) | 161 patients with a first episode of non-affective psychosis and no prior treatment | SAPS | Six times | 6 weeks | Sum score | Group-based trajectory modelling | Five: responders (36/22.4), dramatic responders (25/15.2), partial responders (58/36.2), slow partial responders (29/17.9), and non-responders (13/8.3) | Duration of untreated psychosis and cannabis use |
| Chen 201357 | USA | Mulitcenter trial study, mental health outpatient clinics | 400 patients with SSD and treated with first- and second-generation antipsychotics | PANSS | Seven times | 1 year | Sum score | Growth mixture modelling | Three: Class 1 (41/10), Class 2 (317/79) and Class 3 (43/11) | Positive and negative symptoms |
| Abdin 201720 | Singapore | Institute of Mental Health/Early Psychosis Intervention Programme (EPIP) clinical database. | 1724 patients with first-episode psychotic disorder and with no prior or treatment <3 months | PANSS | Five times | 2 years | Not clearly reported | Latent class growth analysis | Two: early response and stable trajectory (/87.7), and delayed response (/12.3) | Gender, educational status, duration of untreated psychosis, diagnosis |
| Negative symptoms | ||||||||||
| Pelayo-Terán et al. 201465 | Spain | University Hospital Marqués de Valdecilla/Clinical Programme on First‐Episode Psychosis of Cantabria (PAFIP) | 161 patients with a first episode of non-affective psychosis and no prior treatment | SANS | Six times | 6 weeks | Sum score | Group-based trajectory modelling | Five: responders (22/18.8), mild non-responders (44/37.3), moderate non-responders (22/18.3), partial responders (13/11) and poor responders (17/14.5) | Schizophrenia diagnosis |
| Abdin 201720 | Singapore | Institute of Mental Health/Early Psychosis Intervention Programme (EPIP) clinical database. | 1724 patients with first-episode psychotic disorder and with no prior or minimal treatment (<12 weeks) | PANSS | Five times | 2 years | Not clearly reported | Latent class growth analysis | Four: early response and stable trajectory (/84), early response and relapse trajectory (/5.9), slower response and no response trajectory (/8.9) and delayed response (/1.2) | Occupational status, educational status, diagnosis |
| Stiekema et al. 201764 | Netherlands | Genetic Risk and Outcome of Psychosis (GROUP) | 1067 patients with nonaffective psychosis | PANSS (social amotivation) | Three times | 6 years | Sum score | Group-based trajectory modelling | Four: low (670/58.0), decreased low (120/14.6), increased (223/21.2), and decreased high (54/6.2) | Age, gender, educational status, ethnicity, marital status, functioning, quality of life, diagnosis, antipsychotics dosage, neurocognitive performance, negative and psosive symptoms |
| Stiekema et al. 201764 | Netherlands | Genetic Risk and Outcome of Psychosis (GROUP) | 1067 patients with nonaffective psychosis | PANSS (expressive deficits) | Three times | 6 years | Sum score | Group-based trajectory modelling | Four: low (715/63.6), decreased (180/16.6), increased (114/13.9) and high (58/5.9) | Age, gender, educational status, ethnicity, marital status, functioning, quality of life, diagnosis, antipsychotics dosage, neurocognitive performance, negative and psosive symptoms |
| Gee 201661 | UK | National EDEN study | 1006 patients with first episode psychosis and receiving treatment for 12 months | PANSS | Three times | 1 year | Mean score | Latent class growth analysis | Four: minimal decreasing (674/63.9), mild stable (108/13.5), high decreasing (174/17.1) and high stable (50/5.4) | Gender, family history of non-affective psychosis, poor premorbid adjustment and depression |
| Austin 201519 | Denmark | Centre for psychiatric research/OPUS trial trail | 496 patients with first-episode SSD and had received <12 weeks of treatment | SANS | Five times | 10 years | Composite score using global scores | Latent class analysis | Four: response (139/28), delayed response (94/19), relapse (129/26) and non-response (134/27) | Gender, social and global functioning, treatment, disorganized symptoms and diagnosis |
| Chen 201357 | USA | Mulitcenter trial study, mental health outpatient clinics | 400 patients with SSD and treated with antipsychotics | PANSS | Seven times | 1 year | Sum score | Growth mixture modelling | Four: Class 1 (44/11), Class 2 (284/71), Class 3 (9/2), and Class 4 (63/16) | Positive and negative symptoms |
| Chan et al. 202067 | Hong Kong, China | Public mental health service centres | 209 patients with first-episode schizophrenia-spectrum disorders | CGI-neg | 64 times | 10 years | Mean score | Ward’s method | Three: low (117/56.0), improving (61/29.2) and relapsed (31/14.8) | Gender, hospitalization, low educational status, unemployment, duration of untreated psychosis, negative symptoms |
| Chang et al. 201858 | Hong Kong, China | Public psychiatric units | 138 patients with first-episode nonaffective psychosis and not received treatment >1 week | HEN | Four times | 3 years | Sum score | Latent class growth analysis | Three: minimal-stable (81/59.6), mild-stable (40/29.4) and high-increasing (15/11.0) | Gender, educational status, premorbid adjustment, cognitive performance, depressive symptoms, positive and negative symptoms |
| Positive and negative symptoms (PANSS total score) | ||||||||||
| Schennach et al. 201260 | German | Multi-centre study/ German Research Network on Schizophrenia (GRNS) | 399 patients with schizophrenia spectrum disorder | PANSS | More than 10 times | >5 months | Sum score | Latent class growth analysis | Five: early and considerable response (61/15), rapid and dramatic response (54/14), early and satisfying response (137/34), gradual response (89/22) and partial response (58/15) | Depressive symptoms at admission, functioning, duration of illness, previous hospitalizations, positive and negative symptoms |
| Stauffer et al. 201156 | USA and other countries | Multicentre study | 1990 patients with chronic schizophrenia and receiving treatment | PANSS | 11 times | ≤6 months | Sum score | Growth mixture modelling | Five: dramatic responders (47/2.4), partial responders (1802/90.6), partial responders-unsustained (late) (32/1.6), partial responders-unsustained (early) (28/1.4) and delayed Responders (81/4.1) | Age, gender, ethnicity, weight, age of onset, depression symptoms, extrapyramidal symptoms, aripiprazole treatment |
| Levine 2010a22 | 12 countries | International cohort/ Johnson & Johnson Pharmaceutical Research and Development | 491 patients with early episode psychosis and receiving treatment for >3 months | PANSS | Six times | 6 months | Sum score | Mixed-mode latent class regression modelling | Five: stable 1 (91/18.3), stable 2 (104/20.9), stable 3 (132/26.6), improved and stable (76/15.3), and marked improvement) (94/18.9) | Diagnosis of schizophrenia, age of onset, cognitive functioning, premorbid functioning |
| Levine 2010b62 | 12 countries | International cohort/ Johnson & Johnson Pharmaceutical Research and Development | 263 patients with early episode psychosis and receiving treatment for >3 months | PANSS | More than six times | 2 years | Sum score | Mixed-mode latent class regression modelling | Five: Trajectory 1 (55/21.0), Trajectory 2 (60/22.9), Trajectory 3 (64/24.4), Trajectory 4 (40/15.2) and Trajectory 5 (44/16.6) | Diagnosis, premorbid functioning, cognitive performance, positive and negative symptoms |
| Case et al. 201117 | 3 countries | 64 research centres | 628 patients with psychosis and treated with antipsychotics | PANSS | Eight times | 3 months | Sum score | Growth-mixture modelling | Four: moderate-gradual (420/80.6), rapid (65/12.5), high-gradual (24/4.6), unsustained (12/2.3) improvement | Extrapyramidal and depression symptoms, quality of life, age at onset of illness, ethnicity, positive and negative symptoms, general psychopathology |
| Chen 201357 | USA | Mulitcenter trial study, mental health outpatient clinics | 400 patients with SSD and treated with first- and second-generation antipsychotics | PANSS | Seven times | 1 year | Sum score | Growth mixture modelling | Three: dramatic and sustained early improvement (70/18), mild and sustained improvement (237/59), and no improvement (82/21) | Positive and negative symptoms |
| Levine et al. 201263 | USA | 57 clinical sites | 1124 patients with chronic schizophrenia and receiving treatment | PANSS | Eight times | 1.5 years | Sum score adjusted for the baseline score | Mixed-mode latent regression modelling | Three: low deteriorators (778/69.2), responders (212/18.9) and high deteriorators (134/11.9) | Type of antipsychotics, exacerbation, positive and negative symptoms |
| Jager 201459 | Germany | ELAN study, psychiatric hospitals | 268 patients with SSD and receiving treatment for >1 year | PANSS | Five times | 2 years | Sum score | Latent class growth analysis | Two: amelioration/decrease in all symptoms (154/60 and stable positive/negative symptoms and deteriorating general psychopathology symptoms (103/40) | Global functioning, gender, age, living situation and involuntary admission |
| Cognitive deficits | ||||||||||
| Habtewold et al. 202066 | Netherlands | Genetic Risk and Outcome of Psychosis (GROUP) | 1119 patients with nonaffective psychosis, 1059 siblings, and 586 controls | NTB | Three times | 6 years | PCA, sum of component scores | Group-based trajectory modelling | Six: very severe (199/0.8), severe (159/6.2), moderate (384/15.1), mild (684/25.8), normal (1056/33.5), and high (462/18.5) | Polygenic risk score of schizophrenia |
| Islam et al. 201852 | Netherlands | Genetic Risk and Outcome of Psychosis (GROUP) | 1119 patients with nonaffective psychosis, 1059 siblings, and 586 controls (results are only for patients) | NTB | Three times | 6 years | Gender and age adjusted z-score and then averaging | Group-based trajectory modelling | Five: severely altered (109/10.7), moderately altered (312/28.4), mildly altered (377/30.4), normal (290/26.7), and high (31/3.8) performer | Education, IQ, premorbid functioning, and positive and negative symptoms |
| Islam et al. 201852 | Netherlands | Genetic Risk and Outcome of Psychosis (GROUP) | 1119 patients with nonaffective psychosis, 1059 siblings, and 586 controls (results are only for siblings) | NTB | Three times | 6 years | Gender and age adjusted z-score and then averaging | Group-based trajectory modelling | Four: moderately altered (132/13.0), mildly altered (260/25.1), normal performer (413/37.6), and high performer (254/24.2) | Age, gender, education, ethnicity, IQ, premorbid functioning, positive symptoms, frequency of psychotic experiences, and neurocognitive performances |
| Thomspson et al. 201316 | USA | University of California, San Diego Advanced Centre in Innovation in Services and Interventions Research (ACISIR) | 201 old clinically stable outpatients with schizophrenia and 67 controls | MDRS | Four times | 3.5 years | Sum score | Latent growth curve model | Three: high and stable (101/50), low and modestly declining (81/42), low and rapidly declining (19/10) | Negative symptoms, living situation, years of education, global cognition |
| Schizotypy | ||||||||||
| Wang et al. 201868 | China | University of Chinese Academy of Sciences/Key Laboratory of Mental Health | 1541 college students | CPPS (4 subscales) | Four times | 1.5 years | Sum score | Latent class growth analysis | Four: non-schizotypy (1113/72.2), stable-high schizotypy (73/4.74), high-reactive schizotypy (142/13.8), low-reactive schizotypy (213/13.8) | Male gender, severe schizotypy |
CGI-neg Clinical Global Impressions-Schizophrenia scale for negative symptoms, CPPS Chapman Psychosis Proneness Scales, HEN High Royds Evaluation of Negativity Scale, MDRS Mattis Dementia Rating Scale, NTB Neuropsychological Test Battery (seven tests were used), PANSS Positive and Negative Syndrome Scale, SANS Scale for the Assessment of Negative Symptoms, SAPS Scale for the Assessment of Positive Symptoms, SSD Schizophrenia spectrum disorder.
aResults from pairwise comparisons, univariable or multivariable logistic regression analyses.