The Diagnostic Interview Schedule for Children Version IV (DISC-IV) was the diagnostic tool used in the survey. It comprises a series of mental disorder modules that implements the criteria for mental disorders set out in the Diagnostic and Statistical Manual of Mental disorders, 4th edition (DSM-IV).
The DISC-IV was used with the permission of Columbia University.
Modules for seven disorders were used in the parent or carer interview in the survey — social phobia, separation anxiety disorder, generalised anxiety disorder, obsessive-compulsive disorder, major depressive disorder, attention-deficit/hyperactivity disorder (ADHD) and conduct disorder.
The DISC-IV module for oppositional defiant disorder was included in the survey. However, unlike other disorders, the diagnosis for oppositional defiant disorder includes an element of clinical judgement that could not be implemented within the DISC questions. In particular, for each symptom assessed in oppositional defiant disorder the DSM-IV specifies that the symptom criterion is met only if the behaviour occurs more frequently than is typically observed in individuals of comparable age and developmental level. A clinician is required to make this judgement. The data collection for Young Minds Matter was undertaken by lay professional interviewers who were not specifically trained in psychology or psychiatry and expert clinical review of each child or adolescent in the survey was not undertaken. As such it was not possible to identify all criteria for assigning the diagnosis of oppositional defiant disorder. Instead these behaviours are referred to as oppositional problem behaviours to distinguish them from the diagnostic condition of oppositional defiant disorder.
All estimates have been derived from the survey sample, and weighted to represent the population of children and families in Australia. The estimates have been rounded, generally to three significant digits. As such, discrepancies may occur between the sums of component items and their totals.
Estimates have been suppressed where there were less than 5 survey respondents contributing to a cell. These appear as blank cells in tables and are omitted from charts.
Estimates are shown along with 95% confidence limits. Because Young Minds Matter was based on a sample and not a full census of Australian children and adolescents, the survey estimates could differ from the results that would be obtained from a full census due to random chance. The 95% confidence limits give an indication of the degree of sampling variability associated with the estimates. As a general rule, estimates that are based on larger numbers of contributing children are more accurate than those where fewer sample children contribute to the estimate. For instance, using the remoteness classification, the prevalence estimates for Major Cities are more accurate than those for Remote Australia because a higher proportion of the sample was located in Major Cities.
As an approximate rule of thumb, when comparing two prevalence estimates, if the ranges for the confidence limits of both estimates overlap, there is a higher chance that any difference between the two figures could be attributed to chance variation. When the ranges of the confidence limits do not overlap there is a greater chance that a full census would also have found a difference in the figures being compared.
Meeting diagnostic criteria according to the DSM-IV (for the purposes of this report) in the 12 months prior to interview. Prevalence includes both new cases, whose symptoms first developed during the 12 months prior to the interview and continuing cases whose symptoms were present prior to the 12 months, but persisted, and were at a level to meet the diagnostic criteria in the 12 months prior to interview.
Negativistic, hostile and defiant behaviours, such as often losing temper, arguing with adults, actively defying adults’ requests and rules, being angry, resentful, spiteful or vindictive, lasting at least six months.
In this survey an exclusion criterion was defined so that children or adolescents who met the diagnostic criteria for conduct disorder were not considered to have oppositional problem behaviours.
Families were classified into families with two parents or carers and families with one parent or carer. Families with two parents or carers were further categorised into original, step, blended or other families corresponding to the Australian Bureau of Statistics family blending classification variable introduced in the 2006 Census. These are defined as follows:
Household income has been split into three approximately equally sized groups. Around 4% of families either didn’t know or refused to provide their household income. These families have been excluded from tables and charts relating to household income.
This classifies people as employed when working full-time, part-time or away from work, or not in employment when unemployed or not in the labour force. Employed includes casual, temporary or part-time work if it was for an hour or more.
For the purposes of the survey this was collected for both parents and carers for the previous week.
The index of relative socio-economic disadvantage is produced by the Australian Bureau of Statistics from the 2011 Census of Population and Housing, and gives a summary measure of the relative socio-economic disadvantage of the Statistical Area 1 (SA1) that the household is located in.
Area of residence was categorised as either Greater Capital Cities or Rest of state based on the Australian Bureau of Statistics Greater Capital City Statistical Area (GCCSA) classification. This classification represents the functional extent of the eight state and territory capital cities in Australia. Households within these areas were classified as Greater Capital Cities. The remainder were classified as Rest of state.
Remoteness areas are based on the Australian Bureau of Statistics Remoteness Area classification for the Statistical Area 1 (SA1) the household is located in.
The top 1% most remote SA1s in Australia were excluded from the sampling frame, and the survey has poor coverage of very remote areas. For output purposes the categories 'Remote Australia' and 'Very Remote Australia' have been combined.
The ABS Remoteness Area classification is based on the Accessibility/Remoteness Index of Australia (ARIA+) produced by the National Centre for Social Application of Geographic Information Systems (GISCA) at the University of Adelaide.
Remoteness area boundaries can be downloaded from the Australian Bureau of Statistics web site www.abs.gov.au
A shortened version of the General Functioning Subscale of the McMaster Family Assessment Device was used to classify families into four levels of functioning. This ranged from very good through to poor, with poor indicating unhealthy family functioning likely to require clinical intervention. Of all families in the survey 3.7% had a poor level of family functioning.
Boterhoven de Haan KL, Hafekost J, Lawrence D, Sawyer MG, Zubrick SR (2014). Reliability and validity of a short version of the general functioning subscale of the McMaster Family Assessment Device. Family Process. doi: 10.1111/famp.12113