Introduction
Methods
CHADS cohort | Sample characteristics | Associated publications |
---|---|---|
1. Pilot study sample (2004–2005) | 548 children aged 9–11 years (mean age 10.6 years; 54.7 % female) and 264 primary caregivers, comprising: 129 children and caregivers who completed questionnaires via General Practitioner surgeries (21.6 % of 597 children enrolled at collaborating surgeries) 421 children (97.7 % of children eligible) who completed questionnaires in school class and 136 caregivers (32.3 %) | [7] |
2a. Community sample (screening) | 7966 children completing questionnaires anonymously in school class (94.6 % of children eligible; mean age 10.4 years; 49.2 % female) and 1504 primary caregivers (18.9 %) | |
2b. Longitudinal community sample | 670 children and caregivers (mean age 10.3 years; 53.4 % female)—the subset of 799 families who provided identities and contact information at screening and whose contact information remained valid at first reassessment approximately 2 years later | |
3. Longitudinal selected sample (biennial assessments) | 111 children and caregivers, comprising: 46 TD; 33 ASz; 26 FHx; and 6 children meeting both ASz and FHx criteriaa
Biennial assessments completed at ages 9–12 years (baseline); 11–14 years (follow-up 1); 13–16 years (follow-up 2); and 17–18 years (follow-up 3) (Note: a further 39 children with alternative illness risk profiles, including bipolar disorder, were recruited in insufficient numbers to provide viable groups for examination) | |
4. CHADS-associated intervention samples | Clinical case series: four children from the community sample who completed a new, manualised cognitive behavioural intervention for children presenting psychotic-like experiences and emotional distress | [74] |
Coping with unusual experiences for children study (CUES): doi 10.1186/ISRCTN13766770 (Lead: Dr. S. Jolley)—for children aged 8–14 years presenting to Child and Adolescent Mental Health Services with unusual experiences and emotional distress | ||
Coping with unusual experiences for 12–18 (CUES+): doi 10.1186/ISRCTN21802136 (Lead: Dr. S. Jolley)—for users of adolescent community mental health services (aged 12–18 years) who report distressing unusual experiences |
Community (cross-sectional and longitudinal) cohorts
Selected longitudinal cohort
Domain | Assessment method (informant) | Assessment instrument | Assessment phase | ||||
---|---|---|---|---|---|---|---|
SCR | BL | FU1 | FU2 | FU3a
| |||
Psychopathology | |||||||
Social, emotional, and behavioural problems | Questionnaire (P, C, T) | ✓ | ✓ | ✓+
| ✓ | ✓ | |
DSM-IV diagnoses and symptoms (including psychotic symptoms) | Interview (P, C) | Kiddie Schedule for Affective Disorders and Schizophrenia—Present and Lifetime version (K-SADS-PL) [87] [primary caregiver: full schedule; child: anxiety and psychotic symptoms (screening and supplement) questions only] | – | ✓ | – | – | – |
Questionnaire (P, C, & T) | Achenbach System of Empirically Based Assessment (ASEBA [88]): Child Behavior Checklist (CBCL), Youth Self-Report (YSR), Teacher Report Form (TRF) | – | ✓ | ✓ | ✓ | ✓ | |
Anxiety symptoms | Questionnaire (C) | Revised Child Manifest Anxiety Scale, second edition (RCMAS-2 [89]) | – | ✓ | ✓ | ✓ | – |
Depressive symptoms | Questionnaire (C) | Beck Depression Inventory for Youth (BDI-Y [90]) | – | ✓ | ✓ | ✓ | – |
Antisocial traits | Questionnaire (P, C) | Antisocial Process Screening Device [91] | – | ✓ | ✓ | ✓ | – |
Autistic symptoms | Questionnaire (P) | Social Communication Questionnaire—lifetime version [92] | – | ✓ | – | – | – |
Psychotic-like experiences | Questionnaire (P, C) | ✓ | ✓ | ✓+
| ✓ | ✓ | |
Prodromal symptoms of psychosis | Questionnaire (C) | Prodromal Questionnaire [93] | – | – | – | ✓ | ✓ |
Psychotic symptoms | Interview (C) | Comprehensive Assessment of At-Risk Mental State (CAARMS [94]) | – | – | – | – | ✓ |
Personality | Questionnaire (P) | Big Five Inventory [95] adapted for Children | – | – | – | ✓ | – |
Global functioning | Interview (C) | Global Assessment of Functioning scale (GAF [96]) | – | ✓ | – | – | ✓ |
Medical and developmental history | |||||||
Developmental delays | Questionnaire (P) | Items assessing delays/problems in the attainment of speech or motor milestones [7] | ✓ | – | – | – | – |
Medical and psychiatric history | Interview (C) | Family Interview for Genetic Studies (FIGS [97]) to identify known medical and psychiatric conditions in the child and other family members | – | ✓ | ✓ | ✓ | – |
Relationships assessment | |||||||
Parenting practices | Questionnaire (P, C) | Alabama Parenting Questionnaire [98] | – | ✓ | ✓ | ✓ | – |
Family functioning | Questionnaire (P) | McMaster Family Assessment Device [99] | – | – | – | ✓ | – |
Expressed emotion | Standardised rating (P) | – | ✓ | ✓ | ✓ | – | |
Child experiences | |||||||
Alcohol and drug use | Questionnaire (C) | Adapted version of the Edinburgh Study of Youth Transitions and Crime alcohol and drug use questionnaires [102] | – | ✓ | ✓ | ✓ | ✓ |
Daily hassles and life events | Questionnaire (C) | Adapted version of a daily school-related hassles and negative life events questionnaire [103] | – | ✓ | ✓ | ✓ | – |
Threatening life events | Questionnaire (C) | List of Threatening Events (LTE [104]) | – | – | – | – | ✓ |
Perceived stress | Questionnaire (C) | Perceived Stress Scale (PSS [105]) | – | – | – | – | ✓ |
Childhood trauma | Questionnaire (C) | Childhood Trauma Questionnaire (CTQ [106]) | – | – | – | – | ✓ |
Victimisation | Interview (C) | Juvenile Victimization Questionnaire 2nd revision (JVQ-R2 [107])—sections on victimisation by peers and siblings, internet/mobile harassment, and discriminatory attacks | – | – | – | – | ✓ |
Self-harm | Questionnaire (C) | Item assessing self-harm in the past 12 months [108] | – | – | – | – | ✓ |
Socio-environmental indices | |||||||
Sociodemographic variables | Questionnaire (P, C) | Items assessing child’s sex, date of birth, and (by caregiver-report only) child’s self-ascribed ethnicity, parents’ dates and places of birth, child and family history of mental health problems, and whether child had ever lived outside London | ✓ | – | – | – | – |
Ethnicity | Questionnaire (P) | Office of Population Censuses and Surveys method of self-ascription (2001 census) | – | ✓ | ✓ | ✓ | – |
Migration history | Questionnaire (P) | Date of migration and country of origin | – | ✓ | ✓ | ✓ | – |
Home, school, and community supports | Questionnaire (C) | Middle Development Index items [109] | – | ✓ | ✓ | ✓ | – |
Sociodemographic context | Questionnaire (P) | UK Medical Research Council Sociodemographic Schedule on housing and living (migration) circumstances; religious engagement | – | ✓ | ✓ | ✓ | – |
Socio-economic Status | Questionnaire (P) | National Statistics Socio-Economic Classification (NS-SEC [110]); household income; educational attainment | – | ✓ | ✓ | ✓ | – |
Financial income | Questionnaire (C) | Items assessing income sources and total income per week | – | – | – | – | ✓ |
Biological indices | |||||||
DNA/mRNA | Buccal sample (C) | Collected at the research session and in home environment | – | ✓ | ✓ | ✓ | ✓ |
Blood sample (C) | Collected at the research session | – | ✓ | ✓ | ✓ | ✓ | |
Cortisol | Saliva samples (C); hair sample (C) | Home collection of multiple saliva samples throughout the day at FU2 [43]; hair sample collected in the research session at FU3 | – | – | ✓ | – | ✓ |
Pubertal status | Questionnaire (P, C) | Pubertal Development Scale [111] | – | ✓ | ✓ | ✓ | – |
Neuromotor function | |||||||
Laterality/handedness | Questionnaire (C) | – | ✓ | ✓ | ✓ | – | |
Gross and fine motor skills | Standardised test (C) | Purdue Pegboard [115] | – | ✓ | ✓ | ✓ | – |
Involuntary dyskinetic movements | Standardised rating (C) | Dyskinesia Identification System Condensed User Scale [116] (coded from video recording) | – | ✓ | – | – | – |
Brain structure and function | |||||||
General intelligence | Standardised test (C) | Wechsler Abbreviated Scale of Intelligence (WASI [117]) | – | ✓ | ✓ | ✓ | ✓ |
Scholastic achievement | Standardised test (C) | Wechsler Individual Achievement Test 2nd UK edition (WIAT [118]): word reading, numerical operations, and spelling subtests | – | ✓ | ✓ | ✓ | – |
Processing speed | Standardised test (C) | Symbol Digit Modality Test [119] | – | – | – | ✓ | – |
Memory | Standardised test (C) | Wide Range Assessment of Memory and Learning 2nd edition (WRAML2 [120]): verbal learning and memory, visual learning and memory, verbal delayed recall, recognition (verbal and nonverbal), and working memory subtests | – | ✓ | ✓ | ✓ | – |
Executive function | Standardised test (C) | Delis-Kaplan Executive Function System (D-KEFS [121]): verbal fluency, colour–word interference (Stroop), and tower test subtests | – | ✓ | ✓ | ✓ | – |
Facial emotion recognition | Computer task (C) | Penn Emotion Discrimination Task (EmoDiff40) [122] | – | ✓ | ✓ | ✓ | – |
Facial emotion discrimination | Computer task (C) | Emotion Recognition Test–40 Faces version (ER-40) [123] | – | ✓ | ✓ | ✓ | – |
Brain structure | Magnetic Resonance Imaging (C) | Spoiled Gradient Recalled acquisition (Magnetization Prepared Rapid Acquisition Gradient Echo—additional scan completed in a subset only) | – | ✓ | ✓ | ✓ | – |
Mismatch negativity | Computer task (C) | Duration deviant passive auditory oddball task: ERP recordings [55] | – | ✓ | ✓ | ✓ | – |
Working memory | Computer task (C) | Spatial N-Back task: functional MRI (variant of [124]) | – | ✓ | ✓ | ✓ | – |
Attention | Computer task (C) | Auditory novelty oddball task: ERP recordings and functional MRI (variant of [125]) | – | ✓ | ✓ | ✓ | – |
Error-related processing | Computer task (C) | Go/No-Go task: ERP recordings and functional MRI [53] | – | ✓ | ✓ | ✓ | – |
Response inhibition | Computer task (C) | Stop task: ERP recordings and functional MRI (variant of [126]) | – | ✓ | ✓ | ✓ | – |
Service use, support, and quality of life | |||||||
Service utilisation | Questionnaire (P, C) | Services Assessment for Children and Adolescents [127] | – | – | ✓+
| – | ✓+
|
Resource access | Questionnaire (P, C) | Resource Generator—UK, expert advice subscale [128] | – | – | ✓+
| – | ✓+
|
Social cohesion | Questionnaire (P, C) | Items assessing neighbourhood social cohesion [129] | – | – | ✓+
| – | ✓+
|
Peer interaction | Questionnaire (C) | Child Health and Illness Profile [130] peer interaction and satisfaction scale | – | – | – | – | ✓+
|
Mental health literacy | Questionnaire (C) | Self-report questionnaires on two vignettes depicting persons with (1) depression and (2) psychosis. Assesses recognition of the disorder, intended help-seeking, beliefs about interventions and prevention, stigmatising attitudes, and exposure to mental disorders [131] | – | – | – | – | ✓+
|
Self-identification as having a mental illness | Questionnaire (C) | Self-Identification as Having a Mental Illness Scale (SELF-I) assessing perceived need for professional help and appraisal of problem as mental illness [132] adapted for young people | – | – | – | – | ✓+
|
Stigma | |||||||
Public stigma | Questionnaire (P, C) | Reported and Intended Behaviour Scale [133] | – | – | ✓+
| – | ✓+
|
Stigma coping | Questionnaire (C) | Items assessing cognitive appraisal of mental health stigma [134] | – | – | – | – | ✓+
|
Related intervention cohorts
Results
Epidemiological findings
Developmental antecedents of SSD
Childhood PLEs
Persistence of PLEs
Trajectories of psychopathology
Psychological, cognitive, and neurobiological findings
Marker | Adult psychosis vs. HC | ASz vs. TD children | FHx vs. TD children |
---|---|---|---|
Psychopathology and stress responsivity | |||
Social withdrawalb
| ↑ | ↑ | ↑ |
Psychosocial stress exposured
| ↑ | ↑ | ↑ |
Psychosocial stress reactivityd
| ↑ | ↑ | ↑ |
Cognitive impairmentsc
| |||
General intelligence (IQ) | ↓ | ↓ | ↓ |
Scholastic achievement | ↓ | ↓ | ↓ |
Verbal memory | ↓ | ↓ | ↓ |
Visual memory | ↓ |
–
|
–
|
Working memory (verbal) | ↓ | ↓ | ↓ |
Executive function (verbal fluency) | ↓ | ↓ | ↓ |
Executive function (inhibition) | ↓ | ↓ | ↓ |
Facial emotional processing ability | ↓ | ↓ | Not examined |
Neurobiological abnormalities | |||
Grey matter volume (left STG/MTG and right MTG)a
| ↓ | ↑ ↓ | Not examined |
White matter volume (left SLF, ILF, and OR)a
| ↓ | ↑ | Not examined |
Error-related negativity ERP component amplitudea
| ↓ | ↓ | Not examined |
Mismatch negativity ERP component amplitudea
| ↓ | ↑ | Not examined |
Dyskinetic movement abnormalitiesa
| ↑ | ↑ | Not examined |
HPA axis dysfunction | |||
Diurnal cortisold
| ↑ | – | – |
Cortisol awakening responsed
| ↓ | – | ↓ |
Pituitary volumed
| ↑ ↓ | – | – |