Tim Croudace | University of Cambridge (original) (raw)

Papers by Tim Croudace

Research paper thumbnail of Association Between Duration of Untreated Psychosis and Outcome In Cohorts of First-Episode Patients: a Systematic Review

Archives of General …, Jan 1, 2005

Research paper thumbnail of Aggressive Incidents In First-Episode Psychosis

The British Journal of …, Jan 1, 2001

Research paper thumbnail of Three-Year Outcome of First-Episode Psychoses In An Established Community Psychiatric Service

The British Journal of …, Jan 1, 2000

Research paper thumbnail of Clinical and Social Determinants of Duration of Untreated Psychosis In the AESOP First-Episode Psychosis Study

The British Journal of …, Jan 1, 2006

Research paper thumbnail of Impact of the ICD-10 Primary Health Care (PHC) diagnostic and management guidelines for mental disorders on detection and outcome in primary care: Cluster …

The British Journal of …, Jan 1, 2003

Research paper thumbnail of Developmental typology of trajectories to nighttime bladder control: epidemiologic application of longitudinal latent class analysis

American journal of …, Jan 1, 2003

Research paper thumbnail of The persistence of developmental markers in childhood and adolescence and risk for schizophrenic psychoses in adult life. A 34-year follow-up of the Northern …

Schizophrenia …, Jan 1, 2004

Research paper thumbnail of A longitudinal typology of symptoms of depression and anxiety over the life course

Biological …, Jan 1, 2007

Little is known about long-term profiles of depressive and anxious symptomatology over the life c... more Little is known about long-term profiles of depressive and anxious symptomatology over the life course and about the developmental determinants of different trajectories. The objective of this study was to identify a novel typology of symptoms of depression and anxiety over the life course and examine its neurodevelopmental antecedents in an epidemiological sample. A longitudinal latent variable analysis was conducted on measures of anxious and depressive symptoms at ages 13, 15, 36, 43, and 53 years among 4627 members of the Medical Research Council National Survey of Health & Development (the British 1946 birth cohort). Early life predictors of class membership were studied with ordinal logistic regression. We identified six distinct profiles up to age 53: absence of symptoms (44.8% of sample); repeated moderate symptoms (33.6%); adult-onset moderate symptoms (11.3%); adolescent symptoms with good adult outcome (5.8%); adult-onset severe symptoms (2.9%); and repeated severe symptoms over the life course (1.7%). Heavier babies had lower likelihood of depressive and anxious symptoms (odds ratio [OR] = .92; 95% confidence interval [CI] .85-.99), whereas delay in first standing (OR = 1.19; 95% CI 1.11-1.28) and walking (OR = 1.22; 95% CI 1.14-1.31) was associated with subsequent higher likelihood of symptoms, controlling for social circumstances and stressful life events during childhood. There was evidence of distinct profiles of depressive and anxious symptomatology over the life course and associations with markers of neurodevelopment. This suggests very early factors are associated with long-term experience of symptoms of depression and anxiety.

Research paper thumbnail of Forty-year psychiatric outcomes following assessment for internalizing disorder in adolescence

American Journal of …, Jan 1, 2007

The aim of this study was to define the long-term psychiatric outcomes of adolescent internalizin... more The aim of this study was to define the long-term psychiatric outcomes of adolescent internalizing disorder in the general population, using data collected over 40 years from a national birth cohort. A total of 3,279 members of the Medical Research Council National Survey of Health and Development (the 1946 British birth cohort) underwent assessments of psychiatric symptoms, primarily anxiety and depression, at ages 13 and 15. Adolescents who had internalizing disorder at both ages 13 and 15 and those who had internalizing disorder at one of the two ages were compared with mentally healthy adolescents on various psychiatric outcomes in adulthood (ages 26-53), including the prevalence of mental disorders, self-reported trouble with "nerves," suicidal ideation, and treatment for psychiatric disorders. About 70% of adolescents who had internalizing disorder at both ages 13 and 15 had mental disorder at age 36, 43, or 53, compared with about 25% of the mentally healthy adolescents. They were also more likely than healthy adolescents to have self-reported "nervous trouble" and to have been treated for psychiatric disorder during adulthood. None of these effects was apparent among subjects who had internalizing disorder at only one of the two adolescent assessments. The long-term psychiatric outcome for adolescents with persistent or recurrent internalizing disorder was poor, whereas the outcome for those who had a single episode was better than expected. The association between adolescent internalizing disorder and poor psychiatric outcomes in adulthood may be mediated by persistence or severity of symptoms in adolescence.

Research paper thumbnail of Psychometric evaluation and predictive validity of Ryff's psychological well-being items in a UK birth cohort sample of women

Health and quality of …, Jan 1, 2006

Research paper thumbnail of Discharged from special hospital under restrictions: a comparison of the fates of psychopaths and the mentally ill

… and Mental Health, Jan 1, 1998

Research paper thumbnail of Residence of incident cohort of psychotic patients after 13 years of follow up

Research paper thumbnail of Birth order and risk for schizophrenia: a 31‐year follow‐up of the Northern Finland 1966 Birth Cohort

Acta Psychiatrica …, Jan 1, 2001

Research paper thumbnail of Randomised trial of a parenting intervention during neonatal intensive care

Archives of disease in …, Jan 1, 2007

Research paper thumbnail of The Short Mood and Feelings Questionnaire (SMFQ): A unidimensional item response theory and categorical data factor analysis of self-report ratings from a …

Journal of abnormal child …, Jan 1, 2006

Research paper thumbnail of Deciding who gets treatment for depression and anxiety: a study of consecutive GP attenders

The British Journal of …, Jan 1, 2005

Research paper thumbnail of Serotonin transporter genotype, morning cortisol and subsequent depression in adolescents

The British Journal of …, Jan 1, 2009

Research paper thumbnail of Developmental Trajectories of Sex‐Typed Behavior in Boys and Girls: A Longitudinal General Population Study of Children Aged 2.5–8 Years

Research paper thumbnail of Juvenile and early adulthood smoking and adult educational achievements—a 31-year follow-up of the Northern Finland 1966 Birth Cohort

… journal of public …, Jan 1, 2001

To investigate the association between juvenile and early adult cigarette smoking and educational... more To investigate the association between juvenile and early adult cigarette smoking and educational achievements up to the age of 31 years. As a part of the follow-up of the North Finland 1966 Birth Cohort (n = 10542) from 1966 to 1997, smoking was assessed at the ages of 14 and 31 by postal questionnaires. The highest level of educational attainment was obtained from the National Education Registry of Statistics Finland up to the age of 31 years. Adult smoking (at age 31) and prolonged smoking (at ages 14 and 31) were both associated with an approximately two- to sixfold, adjusted odds for educational underachievement. Smoking only at age 14 showed none of these associations. These results are unlikely to be causal, but may be explained by other characteristics associated with smoking such as personality or lifestyle factors, as well as the effect of knowledge related to smoking gained during higher education.

Research paper thumbnail of A modelling strategy for the analysis of clinical trials with partly missing longitudinal data

International Journal of …, Jan 1, 2003

Standard statistical analyses of randomized controlled trials with partially missing outcome data... more Standard statistical analyses of randomized controlled trials with partially missing outcome data often exclude valuable information from individuals with incomplete follow-up. This may lead to biased estimates of the intervention effect and loss of precision. We consider a randomized trial with a repeatedly measured outcome, in which the value of the outcome on the final occasion is of primary interest. We propose a modelling strategy in which the model is successively extended to include baseline values of the outcome, then intermediate values of the outcome, and finally values of other outcome variables. Likelihood-based estimation of random effects models is used, allowing the incorporation of data from individuals with some missing outcomes. Each estimated intervention effect is free of non-response bias under a different missing-at-random assumption. These assumptions become more plausible as the more complex models are fitted, so we propose using the trend in estimated intervention effects to assess the nature of any non-response bias. The methods are applied to data from a trial comparing intensive case management with standard case management for severely psychotic patients. All models give similar estimates of the intervention effect and we conclude that non-response bias is likely to be small.

Research paper thumbnail of Association Between Duration of Untreated Psychosis and Outcome In Cohorts of First-Episode Patients: a Systematic Review

Archives of General …, Jan 1, 2005

Research paper thumbnail of Aggressive Incidents In First-Episode Psychosis

The British Journal of …, Jan 1, 2001

Research paper thumbnail of Three-Year Outcome of First-Episode Psychoses In An Established Community Psychiatric Service

The British Journal of …, Jan 1, 2000

Research paper thumbnail of Clinical and Social Determinants of Duration of Untreated Psychosis In the AESOP First-Episode Psychosis Study

The British Journal of …, Jan 1, 2006

Research paper thumbnail of Impact of the ICD-10 Primary Health Care (PHC) diagnostic and management guidelines for mental disorders on detection and outcome in primary care: Cluster …

The British Journal of …, Jan 1, 2003

Research paper thumbnail of Developmental typology of trajectories to nighttime bladder control: epidemiologic application of longitudinal latent class analysis

American journal of …, Jan 1, 2003

Research paper thumbnail of The persistence of developmental markers in childhood and adolescence and risk for schizophrenic psychoses in adult life. A 34-year follow-up of the Northern …

Schizophrenia …, Jan 1, 2004

Research paper thumbnail of A longitudinal typology of symptoms of depression and anxiety over the life course

Biological …, Jan 1, 2007

Little is known about long-term profiles of depressive and anxious symptomatology over the life c... more Little is known about long-term profiles of depressive and anxious symptomatology over the life course and about the developmental determinants of different trajectories. The objective of this study was to identify a novel typology of symptoms of depression and anxiety over the life course and examine its neurodevelopmental antecedents in an epidemiological sample. A longitudinal latent variable analysis was conducted on measures of anxious and depressive symptoms at ages 13, 15, 36, 43, and 53 years among 4627 members of the Medical Research Council National Survey of Health & Development (the British 1946 birth cohort). Early life predictors of class membership were studied with ordinal logistic regression. We identified six distinct profiles up to age 53: absence of symptoms (44.8% of sample); repeated moderate symptoms (33.6%); adult-onset moderate symptoms (11.3%); adolescent symptoms with good adult outcome (5.8%); adult-onset severe symptoms (2.9%); and repeated severe symptoms over the life course (1.7%). Heavier babies had lower likelihood of depressive and anxious symptoms (odds ratio [OR] = .92; 95% confidence interval [CI] .85-.99), whereas delay in first standing (OR = 1.19; 95% CI 1.11-1.28) and walking (OR = 1.22; 95% CI 1.14-1.31) was associated with subsequent higher likelihood of symptoms, controlling for social circumstances and stressful life events during childhood. There was evidence of distinct profiles of depressive and anxious symptomatology over the life course and associations with markers of neurodevelopment. This suggests very early factors are associated with long-term experience of symptoms of depression and anxiety.

Research paper thumbnail of Forty-year psychiatric outcomes following assessment for internalizing disorder in adolescence

American Journal of …, Jan 1, 2007

The aim of this study was to define the long-term psychiatric outcomes of adolescent internalizin... more The aim of this study was to define the long-term psychiatric outcomes of adolescent internalizing disorder in the general population, using data collected over 40 years from a national birth cohort. A total of 3,279 members of the Medical Research Council National Survey of Health and Development (the 1946 British birth cohort) underwent assessments of psychiatric symptoms, primarily anxiety and depression, at ages 13 and 15. Adolescents who had internalizing disorder at both ages 13 and 15 and those who had internalizing disorder at one of the two ages were compared with mentally healthy adolescents on various psychiatric outcomes in adulthood (ages 26-53), including the prevalence of mental disorders, self-reported trouble with "nerves," suicidal ideation, and treatment for psychiatric disorders. About 70% of adolescents who had internalizing disorder at both ages 13 and 15 had mental disorder at age 36, 43, or 53, compared with about 25% of the mentally healthy adolescents. They were also more likely than healthy adolescents to have self-reported "nervous trouble" and to have been treated for psychiatric disorder during adulthood. None of these effects was apparent among subjects who had internalizing disorder at only one of the two adolescent assessments. The long-term psychiatric outcome for adolescents with persistent or recurrent internalizing disorder was poor, whereas the outcome for those who had a single episode was better than expected. The association between adolescent internalizing disorder and poor psychiatric outcomes in adulthood may be mediated by persistence or severity of symptoms in adolescence.

Research paper thumbnail of Psychometric evaluation and predictive validity of Ryff's psychological well-being items in a UK birth cohort sample of women

Health and quality of …, Jan 1, 2006

Research paper thumbnail of Discharged from special hospital under restrictions: a comparison of the fates of psychopaths and the mentally ill

… and Mental Health, Jan 1, 1998

Research paper thumbnail of Residence of incident cohort of psychotic patients after 13 years of follow up

Research paper thumbnail of Birth order and risk for schizophrenia: a 31‐year follow‐up of the Northern Finland 1966 Birth Cohort

Acta Psychiatrica …, Jan 1, 2001

Research paper thumbnail of Randomised trial of a parenting intervention during neonatal intensive care

Archives of disease in …, Jan 1, 2007

Research paper thumbnail of The Short Mood and Feelings Questionnaire (SMFQ): A unidimensional item response theory and categorical data factor analysis of self-report ratings from a …

Journal of abnormal child …, Jan 1, 2006

Research paper thumbnail of Deciding who gets treatment for depression and anxiety: a study of consecutive GP attenders

The British Journal of …, Jan 1, 2005

Research paper thumbnail of Serotonin transporter genotype, morning cortisol and subsequent depression in adolescents

The British Journal of …, Jan 1, 2009

Research paper thumbnail of Developmental Trajectories of Sex‐Typed Behavior in Boys and Girls: A Longitudinal General Population Study of Children Aged 2.5–8 Years

Research paper thumbnail of Juvenile and early adulthood smoking and adult educational achievements—a 31-year follow-up of the Northern Finland 1966 Birth Cohort

… journal of public …, Jan 1, 2001

To investigate the association between juvenile and early adult cigarette smoking and educational... more To investigate the association between juvenile and early adult cigarette smoking and educational achievements up to the age of 31 years. As a part of the follow-up of the North Finland 1966 Birth Cohort (n = 10542) from 1966 to 1997, smoking was assessed at the ages of 14 and 31 by postal questionnaires. The highest level of educational attainment was obtained from the National Education Registry of Statistics Finland up to the age of 31 years. Adult smoking (at age 31) and prolonged smoking (at ages 14 and 31) were both associated with an approximately two- to sixfold, adjusted odds for educational underachievement. Smoking only at age 14 showed none of these associations. These results are unlikely to be causal, but may be explained by other characteristics associated with smoking such as personality or lifestyle factors, as well as the effect of knowledge related to smoking gained during higher education.

Research paper thumbnail of A modelling strategy for the analysis of clinical trials with partly missing longitudinal data

International Journal of …, Jan 1, 2003

Standard statistical analyses of randomized controlled trials with partially missing outcome data... more Standard statistical analyses of randomized controlled trials with partially missing outcome data often exclude valuable information from individuals with incomplete follow-up. This may lead to biased estimates of the intervention effect and loss of precision. We consider a randomized trial with a repeatedly measured outcome, in which the value of the outcome on the final occasion is of primary interest. We propose a modelling strategy in which the model is successively extended to include baseline values of the outcome, then intermediate values of the outcome, and finally values of other outcome variables. Likelihood-based estimation of random effects models is used, allowing the incorporation of data from individuals with some missing outcomes. Each estimated intervention effect is free of non-response bias under a different missing-at-random assumption. These assumptions become more plausible as the more complex models are fitted, so we propose using the trend in estimated intervention effects to assess the nature of any non-response bias. The methods are applied to data from a trial comparing intensive case management with standard case management for severely psychotic patients. All models give similar estimates of the intervention effect and we conclude that non-response bias is likely to be small.