Abstract
The Australian National Survey of 2007 is a work of signal importance. It reassuringly confirms many of the findings of its 1997 predecessor, while providing invaluable new information for policy makers. Readers should be aware that the papers in this issue are only a preliminary glimpse of what will come with more detailed analyses of the full data file. Only basic tables prepared by the Australian Bureau of Statistics were available when these papers were written, but it is already apparent that the 2007 Survey will drive further service improvements. Its scientific value [1] for classification, aetiology or the course of mental disorders will become more apparent as analyses progress.
The National Survey 10 years earlier was influential in contributing to some major changes in services for mental health as a result of the >150 peer-reviewed publications it produced. This second National Survey places Australia among a select group, because very few countries have undertaken a repeat survey after a decade, mainly due to the time, effort and resources required. It has to be asked, what do we know from this survey that was not known before?
Coverage
Why was the 2007 Survey undertaken? To determine how many people met criteria for which mental disorder, how disabled they were and what services they used and needed. Most developed countries need such health surveys on a regular basis to evaluate whether policy changes have had the desired effects and, if not, to guide further changes. The 1997 Survey showed that some 20% of the adult population met ICD-10 criteria for one or more of the common mental disorders – affective, anxiety or substance use disorders – in the past 12 months, but that only 38% reported seeing a health professional for a mental health consultation. Concerned by the unmet need in psychiatry [2], the Australian Government developed two important programmes to increase access to and provision of psychological services for people with the common mental disorders who consulted primary care physicians. A second national survey that collected more detailed data on service utilization should determine whether these initiatives have been successful in increasing treated prevalence.
Since 1997 the World Mental Health series of surveys [3] have taken place in some 28 countries, most recently in New Zealand. The 1997 survey used the CIDI-2.1 and gathered data on symptoms of mental disorders occurring in the 12 months prior to interview. The World Mental Health surveys used CIDI-3.0 and enquired about the occurrence of symptoms at any time in the person's lifetime, then used the recency question, ‘When was the last time you had problems like……?’ (listing the symptoms of the disorder of interest) to indicate whether the person would be likely to have met criteria for this disorder in the past year or, indeed, in the past month. There was therefore considerable interest in using the CIDI-3.0 to gather lifetime data, using exactly the same method used in the New Zealand survey.
Unlike its predecessor, the 2007 Survey did not consider children and young people under 16, who make up one-quarter of the national population, nor those with the low-prevalence disorders who so greatly need, and deserve, psychiatric and social services, at great cost. Planning for these two surveys to be conducted in 2010 is nearly complete, but whether funding will be made available is uncertain. It would be a serious omission if these surveys were not done.
Two impediments
Before making any conclusions from the findings reported here, readers are cautioned that the Survey is characterized by two unavoidable impediments. First, only 60% of the target sample were interviewed; almost nothing is known about 40% of the adult population and the attempt to determine their characteristics is not altogether reassuring. Second, as acknowledged by some of the authors, all the information obtained came from the respondents themselves, of whom one in five had symptoms that met criteria for a mental disorder at some point in the previous 12 months. One in 10 would have been symptomatic at the time of interview, so their responses and recall are likely to have been affected. A bias of particular relevance is in reports of satisfaction with services received. It is well established that persons with anxiety or depression, and personality traits conferring vulnerability to these, will be less satisfied, on average, with the support they received, personal or professional, regardless of what they actually received.
There are further limitations that may not warrant too much emphasis. The interview lasted on average 90 min. For some, presumably those with many symptoms, the interview must have taken nearer to 3 h. Respondents also had to be fluent in English to take part. The CIDI version used precludes direct comparison with the 1997 Survey. It elicits information about symptoms experienced across a lifetime, not primarily in the previous 12 months as in 1997; the wording differed in many parts, so responses will be different; and the threshold for recognizing a ‘case’ is probably lower.
We have strong reservations about estimates of lifetime prevalence. The recurrent words in most stems are ‘Have you ever ….?’ Ernest Gruenberg, an eminent psychiatric epidemiologist, deplored such an instrument because it expects people, some of whom may be depressed or anxious at the time, accurately to scour every past year of their lives. The information this yields can be only an approximation of what was really experienced. Gruenberg called it ‘the McCarthy question’.
Slade et al. say, in this issue, that the advantage of using the WHO CIDI was that it ‘facilitates comparability with geographically and economically diverse countries’. That may be so, if account is not taken of large variations in response rates between countries: 46% in France, 60% in Australia, 73% in New Zealand and 88% in Colombia. Given such a range, any international comparisons must be tentative. Furthermore, the prevalence rates reported here are using ICD-10, but they will have to be recalculated to meet the DSM-IV criteria to compare with the Kessler and Üstün data [3]. As in other international studies, a compromise has been made for Australia's survey to allow comparison with other countries, but at the cost of reduced comparability with the 1997 survey.
Information on morbidity will be enriched when analyses can be done of continuous symptom measures. There is increasing agreement that looking upon mental disorders as binary states is useful for some purposes, both clinical and administrative. But the world of mental disorders is not really categorical. To be a ‘case’ as detected by the CIDI, the respondent has to meet certain cut-offs. The population is seen to consist of cases (one in five in the previous 12 months) and non-cases (four in five). But mental health or ill-health is really a continuum. Fortunately, the Survey also included a brief symptom inventory, the K-10, the findings from which may prove invaluable. Because it was used in the 1997 Survey, this is one measure for which it will be possible to see if the frequency distribution has changed over 10 years.
Comorbidity
Several papers deal with comorbidity between anxiety, affective and substance use disorders, and with physical disorders. Schizophrenia and other psychoses are not included. There is increasing recognition that overlap among any of the common mental disorders, within the one individual, may in part be attributable to the fallacy of accepting anxiety or depression as discrete, categorical syndromes [4]. This has so far not been acknowledged in the analyses.
Use of services
The use of services was made a deliberate and major emphasis in the 2007 Survey. The preliminary findings suggest that among people with a common mental disorder, more are coming forward to seek help; and more report their need as having been met. This could be attributed in part to the changes in access to care that followed the 1997 Survey. Of particular note is the twofold increase in the use of psychologists for non-pharmacological treatment through referral by a general practitioner. Here is an example of a change in service availability that was stimulated by the findings of the 1997 Survey. But a fundamental matter is raised by Meadows and Burgess in this issue: among people with a mental disorder in the past year, 57% did not think they needed help. Even more strikingly, of those with a mental disorder who were indeed not receiving treatment, 86% said they did not need any type of help, such as counselling or medication. These are the ‘non-complaining neurotics’ investigated in the 1960s by Foulds [5]. As Whiteford and Groves emphasize in their paper, they are an important group to better understand. We do not know why they do not want help. Are they simply unaware of their state through incomplete mental health literacy, or are they ‘cracking hardy’, defined in the Australian National Dictionary as prepared ‘to feign equanimity’?
We very much look forward to seeing more detailed analyses of the findings of the 2007 survey. We particularly await analyses that assess the effects of policy changes made since 1997 and those that will point to ways of further improving mental health services.