Lifetime and current prevalence of common DSM-IV mental disorders, their demographic correlates, and association with service utilisation and disability in older Australian adults.

Objective: To describe lifetime and 12 month prevalence of common DSM-IV mental disorders, their demographic correlates, and association with service utilisation and disability in Australians aged 65-85 years of age.

Methods: The sample included Australian residents aged 65-85 years who participated in the 2007 Australian National Survey of Mental Health and Well-being (n=1905). The prevalence of DSM-IV mental disorders was estimated using the lay-interviewer administered World Mental Health version of the Composite International Diagnostic Interview.

Structure of the DSM-5 generalized anxiety disorder criteria among a large community sample of worriers.

Background: There is growing empirical and clinical consensus that many psychiatric disorders are continuous in nature. The DSM-5 however makes a categorical distinction between subthreshold and threshold cases of generalized anxiety disorder (GAD). This study tested the a priori assumption that the DSM-5 criteria identify a break in psychopathology between subthreshold and threshold cases of GAD.

Relationship between measurement invariance and age-related differences in the prevalence of generalized anxiety disorder.

Background: Generalized anxiety disorder (GAD) peaks in prevalence in middle age and declines in prevalence into old age. Some commentators have suggested that this is not a meaningful epidemiological trend rather a methodological artifact. This study tested this hypothesis by matching respondents of different ages based on their severity and examining whether age influences the probability of endorsing GAD criteria and the prevalence of GAD.

The 10-item Kessler psychological distress scale (K10) as a screening instrument in older individuals.

Objective: To provide population-based Kessler Psychological Distress Scale (K10) normative data for older adults and cut scores for screening.

Participants: Adults age ≥65 years who participated in either the 1997 or 2007 Australian National Surveys of Mental Health and Well-being (N = 3,697).

Measurements: The proportion of respondents who reported psychological distress, and the correspondence of K10 scores with diagnosis of mental disorder, disability, and service use.

Psychological distress across the lifespan: examining age-related item bias in the Kessler 6 Psychological Distress Scale.

Background: Old age respondents may differ systemically in their responses to measures of psychological distress over and above their actual latent distress levels when compared to younger respondents. The current study aimed to investigate the potential for age-related bias(es) in the Kessler 6 Psychological Distress Scale (K6) items.

Methods: Data from the 2007 Australian National Survey of Mental Health and Wellbeing were analyzed using Item Response Theory to detect the presence of item bias in each of the K6 items.

The long-term effects of traumatic brain injury on the coordinative function of the central executive.

The objective of this study was to compare the coordinative function of the central executive of working memory in matched groups of controls and persons with traumatic brain injury (TBI) with long-term impairments in functioning, using a dual-task paradigm. The dual-task procedure required participants to complete digit span and tracing tasks separately and then together to produce a change index that reflects loss of productivity on the dual trial. A TBI group and a matched group of controls were compared on this task and on ratings of social competency and neuropsychological tests.

Childhood neuropsychological deficits associated with adult obsessive-compulsive disorder.

Background: Existing neuropsychological studies of obsessive-compulsive disorder (OCD) are cross-sectional and do not provide evidence of whether deficits are trait-related (antecedent and independent of symptomatology) or state-related (a consequence, dependent on symptomatology).

Aims: To investigate whether there are premorbid neuropsychological deficits associated with adult OCD.

Method: Longitudinal data were collected from participants of the Dunedin Multidisciplinary Health and Developmental study.

DSM-IV Major Depressive Episode in the elderly: the relationship between the number and the type of depressive symptoms and impairment.

Background: There is a lack of studies that assess whether the DSM-IV criteria for Major Depressive Episode (MDE) that use a diagnostic threshold are valid for the elderly and whether each symptom of depression contributes equally to impairment in this group.

Method: The Australian National Survey of Mental Health and Wellbeing is a population-based epidemiological survey which utilized the Composite International Diagnostic Instrument to diagnose MDE. Analyses were based on the survey respondents who endorsed either (or both) the "depressed mood" or "loss of interest" core MDE symptoms (60+ years, n=278; 40+ years, n=1020).

Impact of substance-induced and general medical condition exclusion criteria on the prevalence of common mental disorders as defined by the CIDI.

Objectives: It has been previously argued that the methodology used by the Composite International Diagnostic Interview version 2.1 to assess the substance-induced and general medical condition exclusion criteria are inadequate. As a result prevalence estimates generated from epidemiological studies using this interview may be underestimated.

Genetic and environmental influences on obsessive-compulsive disorder.

It is important to understand how genetic and environmental factors interact in the development of obsessive-compulsive disorder (OCD) in order to provide a cohesive model of the underlying pathogenic mechanisms. In this article, we provide an overview of the current knowledge of possible genetic and environmental contributions to the development of OCD. We consider the significant challenges for identifying risk factors for OCD as well as promising avenues for overcoming these obstacles in future research.

Age shall not weary them: mental health in the middle-aged and the elderly.

Objective: The prevalence of mental disorders in the elderly is disputed. The debate in this area can be informed by data from large population surveys that contain sufficient elderly participants. The aim of the present paper was to provide the first direct comparison of the prevalence and demographic correlates of ICD-10 anxiety and affective disorders in the middle-aged and the elderly.

Effects of sociodemographic and health variables on Mini-Mental State Exam scores in older Australians.

Objective: This article examines the influence of sociodemographic, biological, and health variables on Mini-Mental State Exam (MMSE) performance, and assesses how the diversity of the population should be reflected in the MMSE cutoff scores used for screening.

Methods: The sociodemographic profiles and MMSE scores of adults aged 65-years and over who participated in the Australian National Mental Health and Well-being Survey were assessed (N = 1,792).

Results: The regression models showed that older age, education levels, language spoken at home and in country of birth, socioeconomic status (SES), occupation, sex, and presence of a mood disorder made significant and unique contributions to performance on the MMSE.

Prevalence of mental disorders in the elderly: the Australian National Mental Health and Well-Being Survey.

Objective: To describe the 1- and 12-month prevalence of mental disorders, their demographic correlates, and their impact on service utilization and disability in individuals 65 years of age and over in a comprehensive epidemiological survey of mental health in Australia.

Methods: A noninstitutionalized national probability sample of elderly Australian residents was interviewed as part of the Australian National Mental Health and Well-being Survey (NMHWS). The prevalence of International Classification of Diseases, Tenth Revision and Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition mental disorders was estimated from the Composite International Diagnostic Interview and other screening instruments.