DIAGNOSTIC EVALUATION FOR AUTISM SPECTRUM DISORDER: A SURVEY OF HEALTH PROFESSIONALS IN AUSTRALIA For peer review only

Transcription

1 DIAGNOSTIC EVALUATION FOR AUTISM SPECTRUM DISORDER: A SURVEY OF HEALTH PROFESSIONALS IN AUSTRALIA Journal: BMJ Open Manuscript ID bmjopen--0 Article Type: Research Date Submitted by the Author: -May- Complete List of Authors: Taylor, Lauren; University of Western Australia, School of Psychology; Cooperative Research Centre for Living with Autism (Autism CRC) Eapen, Valsamma; South Western Sydney Local Health District, ICAMHS; University of New South Wales, School of Psychiatry Maybery, Murray; University of Western Australia, School of Psychology; Cooperative Research Centre for Living with Autism (Autism CRC) Midford, Suzanne; Western Australian Autism Diagnostician's Forum Paynter, Jessica; The AEIOU Foundation, Research Department Quarmby, Lyndsay; University of Tasmania, Centre for Rural Health Smith, Timothy; Disability Services Commission Williams, Katrina; University of Melbourne, Developmental Medicine Whitehouse, Andrew; Telethon Kids' Institute; Cooperative Research Centre for Living with Autism (Autism CRC) <b>primary Subject Heading</b>: Health policy Secondary Subject Heading: Paediatrics Keywords: Autism Spectrum Disorder, Diagnosis, Health policy < HEALTH SERVICES ADMINISTRATION & MANAGEMENT BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

2 Page of BMJ Open DIAGNOSTIC EVALUATION FOR AUTISM SPECTRUM DISORDER: A SURVEY OF HEALTH PROFESSIONALS IN AUSTRALIA Lauren J. Taylor,, Valsamma Eapen,, Murray T. Maybery,, Sue Midford, Jessica Paynter,, Lyndsay Quarmby, Timothy Smith,, Katrina Williams,,,, Andrew J. O. Whitehouse,. School of Psychology, The University of Western Australia, Australia. University of New South Wales, New South Wales, Australia. Western Australian Autism Diagnostician s Forum, Western Australia, Australia. Research Department, AEIOU Foundation, Queensland, Australia. Centre for Rural Health, University of Tasmania, Australia. Disability Services Commission, Western Australia, Australia. Department of Paediatrics, University of Melbourne, Melbourne, Australia. Developmental Medicine, Royal Children s Hospital, Melbourne, Australia. Murdoch Children s Research Institute, Melbourne, Australia. Telethon Kids Institute, The University of Western Australia, Australia. Cooperative Research Centre for Living with Autism (Autism CRC), Brisbane, Queensland, Australia *Corresponding Author: Word count: Lauren Taylor School of Psychology, Henry Wellcome Building Institute of Psychiatry, Psychology and Neuroscience King s College London De Crespigny Park London SE AF lauren.taylor@kcl.ac.uk + (0) 00 BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

3 Page of Abstract Objectives: There is currently no agreed Australian standard for diagnosis of Autism Spectrum Disorder (ASD) even though there are specific diagnostic services available. We suspected inconsistent diagnostic practices for health professionals in Australia and aimed to assess these practices across the nation by surveying all relevant professional groups. Design: In this study, we completed a survey of health professionals whose clinical practice includes participating in the diagnostic process for ASD in Australia. Participants completed an online questionnaire which included questions about their diagnostic setting, diagnostic practice and diagnostic outcomes in -. Participants: Participants covered a range of disciplines including paediatrics, psychiatry, psychology, speech pathology and occupational therapy. All states and territories of Australia were represented. Setting: Participants came from a range of service settings which included hospitals, nongovernment organisations, publicly funded diagnostic services and private practice. Results: There was considerable variability in diagnostic practices for ASD in Australia. While some clinicians work within a multidisciplinary assessment team, others practice independently and rarely collaborate with other clinicians to make a diagnostic decision. Only half of the respondents reported that they include a standardized objective assessment tool such as the Autism Diagnostic Observation Schedule in ASD assessments, and one third indicated that they do not include measures of development, cognition and language in assessments where ASD is suspected. Conclusions: Reported practice of some professionals in Australia may not be consistent with international best practice guidelines for ASD diagnosis. These findings highlight the need for a minimum national standard for ASD diagnosis throughout Australia that ensures best practice regardless of the type of setting in which the service is provided. Key Words: Autism Spectrum Disorder; Diagnosis; Australia BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

4 Page of BMJ Open Strengths and Limitations of this study This is the first national study to investigate the diagnostic practices of health professionals from different disciplines across Australia. While the study included clinicians from a range of professional backgrounds, there were an unequal number of respondents from each professional group. Respondents were self-selected and likely to be committed to high standards of clinical practice. The findings may not represent the diagnostic practices of the broader population of health professionals in Australia. BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

5 Page of DIAGNOSTIC EVALUATION FOR AUTISM SPECTRUM DISORDER: A SURVEY OF HEALTH PROFESSIONALS IN AUSTRALIA In the absence of biomarkers, diagnosis of Autism Spectrum Disorder (ASD) is based on the behavioural presentation of an individual. The gold standard in ASD diagnosis is a best estimate clinical diagnosis which is determined in accordance with current diagnostic classification systems and following rigorous assessment practices. There is general consensus that a rigorous diagnostic assessment for ASD would consist of a physical examination, hearing test, child observation and parent interview which includes a full developmental history (NICE, ). Best-practice ASD assessments are more comprehensive, and also comprise standardised developmental or cognitive testing, language assessment and information from more than one setting, ideally from a source other than the parent or carer who has been interviewed (Anagnostou et al., ; Baird et al., 0; Filipek et al., 00; NICE, ; Ozonoff et al., 0). Rigorous assessments enhance the accuracy of diagnoses and provide information about an individual s strengths and difficulties which is important for intervention planning. Despite the internationally recognised best practice guidelines for ASD diagnosis (e.g. NICE, ), and position statements from professional bodies (Australian Advisory Board on Autism Spectrum Disorder, ; Royal Australasian College of Physicians, 0; Western Australian Autism Diagnostician s Forum; see also Glasson et al., 0) Australia does not have a national standard for ASD diagnosis. In addition, health services are governed on a state or territory basis, rather than a national level. While in some jurisdictions, eligibility for publiclyfunded intervention for children with ASD requires a diagnosis made by a multidisciplinary team comprising a medical professional, psychologist and speech pathologist, other states have less stringent criteria, requiring only a pediatrician or psychiatrist. Furthermore, eligibility for funding from the Helping Children with Autism funding package is determined following a conclusive ASD diagnosis which can be provided by a single paediatrician or psychiatrist (Australian Government, ). Identifying ASD accurately and early is essential given that state and federal funding for early intervention is based on a formal diagnosis made before a child turns seven (Australian Government, ). An inaccurate diagnosis may mean that children are not eligible for early BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

6 Page of BMJ Open intervention which contains elements that specifically focus on areas of difficulty in ASD (Prior et al., ). Alternatively, children who are misdiagnosed with ASD may access services that are not relevant or effective for their areas of difficulty thereby wasting resources. In addition, it is well established that early intervention improves outcomes for children with ASD (Magiati et al., ; Reichow et al., ) and that children who start intervention at a young age make more improvements than children who start at an older age (Fenske et al., ; Granpeesheh et al., 0; Rogers et al., ). While ASD can be reliably diagnosed at two years (Cox et al., ; Moore & Goodson, 0; Eaves & Ho, 0), the average age of diagnosis in Australia is over four years ( months), with ASD most frequently diagnosed at months (Bent et al., ). Variability in the age of diagnosis has been observed between Australian states, with significantly earlier age of diagnosis in Western Australia and New South Wales relative to all other states and territories. The variation in age at diagnosis may be associated with inconsistent diagnostic practices across the nation. While two previous studies have investigated diagnostic practices for ASD in Australia, this research has included only paediatricians (Randall et al., ; Skellern et al., 0) and child psychiatrists (Skellern et al., 0). Skellern et al. (0) examined the assessment practices of pediatricians (N = ) and child psychiatrists (N = ) in Queensland, finding considerable variability in the diagnostic practices of these clinicians. The results of a more recent survey revealed similar findings. In a study of paediatricians across Australia, Randall et al. () found that only a minority of participating clinicians usually included information from cognitive/developmental assessments, or involved other disciplines in the diagnostic process. These practices are inconsistent with current clinical guidelines (NICE, ; Silove et al., 0) for ASD diagnosis. The lack of consistent standards in Australia likely results in different diagnostic protocols and variability in the quality and accuracy of ASD diagnoses. To date, no national research has been conducted to investigate diagnostic practices for ASD across all health professions and throughout Australia. We aimed to survey a representative sample of clinicians including a range of disciplines, states, and service settings. In this study, we compared diagnostic practices for ASD across the Australian states and between clinicians who are experienced in the assessment and diagnosis of ASD. Given that there is no national standard for ASD diagnosis, it was hypothesized that there would be variability in diagnostic practices across states and between clinicians. BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

7 Page of Participants Method Participants were recruited via the large network of the Cooperative Research Centre for Living with Autism (Autism CRC). The Autism CRC is a national cooperative research effort focused on ASD across the lifespan which includes universities, government agencies, service providers, Autism awareness groups and professional bodies. Information about the survey was also distributed through professional organizations such as Speech Pathology Australia, the National Rural Health Alliance, Neurodevelopmental and Behavioural Paediatric Society of Australasia and the Western Australian Autism Diagnostician s Forum. While respondents started the questionnaire, complete responses were obtained from only respondents (%). All states and territories, as well as all disciplines included in multidisciplinary assessments for ASD were represented (see Table ). There was a similar number of responses from the public/non-government (N =, %) and private (N = 0, %) sectors, with % respondents working in both the public and private sectors. A similar proportion of the respondents worked as sole practitioners (%) and within a multidisciplinary team (%), with % of respondents following other models of practice, e.g., working as a sole practitioner and within a multidisciplinary team (MDT). While there was no significant difference in the proportion of practitioners working in MDTs or as sole practitioners across states, χ (, N = ) =., p =.0, Φ =., there was a higher proportion of MDT practitioners in the public (%), relative to the private (%) sector, χ (, N = ) =., p <.00, Φ =.. In addition, a higher proportion of sole practitioners came from the private (%) relative to the public (%) sector. [Insert Table about here] There are six Australian states, New South Wales (NSW), South Australia (SA), Victoria (Vic), Queensland (Qld), Tasmania (Tas) and Western Australia (WA), and two territories, the Australian Capital Territory (ACT) and the Northern Territory (NT). Participants who reported that they had part time employment in the public and the private sectors were asked to indicate which setting was their primary setting, i.e., where they spend more than 0% of their time. All responses were then based on the primary practice setting. BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

8 Page of BMJ Open Participants had been involved in ASD diagnosis for a median of. years (SD =.0 years, Range -0 years). Seventy-six participants (%) had completed training in ASD assessment. Training consisted of either undergraduate or postgraduate education, supervision, case discussions or participation in courses for the administration of the Autism Diagnostic Observation Schedule (ADOS; Lord et al., ), Autism Diagnostic Interview-Revised (ADI-R; Rutter et al., 0) or Developmental, Dimensional, and Diagnostic Interview (Di; Skuse et al., 0). Procedure Participants completed an anonymous -item questionnaire that was presented via Qualtrics (Qualtrics, Utah), an online survey platform. The survey was initially piloted by eight clinicians and researchers with expertise in ASD and revised based on feedback from this group prior to administration. The survey contained questions that fell into three categories: () diagnostic service, () diagnostic practice and () diagnostic outcomes (see Appendix A for more information on the types of questions included in the survey). Background information, such as discipline, years of professional experience and type of training the respondent had participated in was also gathered. Participants indicated whether they worked in a private or public (hospital, government), or in a non-government organisation. Public and non-government organisations were grouped together in the survey and throughout the analysis. Questions were presented in a categorical format (Yes/No), or on a -point Likert scale which ranged from (Never) to (Always). Some questions, such as the number of assessments completed in the past months, required a numerical response. Respondents also provided some percentage responses, e.g., the percentage of assessments in which they collaborate with other professionals. A copy of the questionnaire is available from the Autism CRC on request. Statistical Analysis Data were analysed based on the number of responses recorded for each question. All data were screened for normality prior to analysis. Nonparametric tests (Kruskal-Wallis and Mann-Whitney U) were used where the data were not normally distributed. Otherwise, continuous data were analyzed using ANOVA, with post-hoc (Scheffe Test) comparisons used BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

9 Page of to follow up significant omnibus ANOVA results. Categorical data were analysed using the chisquare test. Results Diagnostic Processes Assessment Sessions and Length. Respondents completed a median of (Range = -.) sessions for ASD assessments with a median assessment length of 0 minutes (SD =. minutes, Range 0-00 minutes). There was no difference in the number of assessment sessions completed in the private (Median =, SD =., Range = 0-.) relative to the public sector (Median =, SD =., Range = -.), U =, p =.0. However, assessment sessions in the public sector (Median = minutes, SD =. minutes, Range = 0-00 minutes) were significantly longer than those in the private sector (Median = 0 minutes, SD =. minutes, Range = 0- minutes), U =, p =.0. Multidisciplinary Assessment. MDTs (N = ) most commonly consisted of one medical and two allied health professionals, usually a psychologist and speech pathologist. All of the participating occupational therapists were part of a MDT. Most MDTs (%) conducted assessments either in series (%), together (%), partially together (%), or in collaboration (%), i.e. each clinician completes an independent assessment, but all assessors meet to make a consensus diagnostic decision. In contrast, sole practitioners tended to complete assessments in isolation (%) or in series (%), i.e. assess an individual independently one after the other. Only small numbers of the sole practitioners reported collaborating with other clinicians, with one of the (%) sole practitioners working in isolation and of those working in series (%) collaborating with external agencies. Multi-Setting Assessment. Most respondents (%) observed the individual in the clinic in all assessments (Median frequency = 0% of assessments, SD = %, Range = 0-0%). Assessments in the home or school/daycare settings were less frequent, with % of respondents including home observations (Median frequency = 0% of assessments, SD = %, Range = 0-0%) and % of respondents including observations in the school or daycare (Median frequency = % of assessments, SD = %, Range = 0-0%). Only two clinicians (%), both from the public sector, include clinic and school/daycare observations in more than % of the BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

10 Page of BMJ Open assessments, with clinicians (%), private practitioners and from the public sector, completing observations in the clinic and home settings. Three respondents (%), from the private sector and one from the public sector, observed a child in the home and school/daycare settings in more than % of the assessments. Wait List Periods. The wait-list period for an ASD assessment was significantly longer in public/ngo (Median = weeks, SD = weeks, range = - weeks) relative to private (Median = weeks, SD =. weeks, Range = - weeks) settings (U =, p <.00) (see Figure ). The wait for a MDT assessment (Median = weeks, SD =., Range =.- weeks) was also longer than for a sole practitioner (Median = weeks, SD =., Range = - ), Mann-Whitney U =, p =.00, perhaps due to the higher number of MDTs in the public sector relative to the private sector [Insert Figure about here] Diagnostic Practices Hearing Test. Of the pediatricians (N = ) surveyed, only two (%) reported that a hearing test is included in all ASD assessments. Another two paediatricians (%) indicated that they rarely include a hearing test in ASD assessments, five reported occasionally or usually (i.e. in in 0-0% of assessments) and pediatricians (%) reported to include a hearing test frequently or usually (i.e. 0-0% of assessments) where ASD is suspected. Medical investigations. All of the paediatricians who include medical investigations in ASD assessments reported completing a genetic screen, Fragile X test and neurological and physical examinations. Of the paediatricians, respondents (%), reported that they include medical investigations frequently or usually (more than 0% of their assessments), with only four pediatricians (%) including medical investigations in all assessments where ASD is suspected. Assessment measures. One-hundred and seven participants responded to questions regarding the administration of assessment tools. A developmental history was reported to have been undertaken by % of respondents. Of these, (%) reported always administering standardised assessments in diagnostic evaluations for ASD, and (%) reported doing so frequently or usually (0-0% of ASD assessments). There was no difference in the proportion BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

11 Page of of respondents who frequently administer assessments in private (N =, %) relative to public (N =, %) service settings, χ (, N = ) =., p =., Φ =., nor were there differences in the proportion of respondents who administer assessments by state, χ (, N = ) =., p =., Φ =.. Participants who reported administering assessments were asked to indicate which types of assessments are included in diagnostic evaluations for ASD. Since some measures are restricted to particular disciplines, it was unsurprising that there was variability in the proportions of clinicians administering cognitive, language and adaptive assessments and measures of ASD symptomatology (see Table ). In addition, only 0 respondents (%) administer the ADOS and (%) the ADI-R. Thirty-two respondents (0%) use the ADOS and the ADI-R together in diagnostic evaluations for ASD. Of the respondents who indicated that they administer assessments as part of diagnostic evaluations for ASD, only (%) reported that they complete an assessment battery comprising measures of developmental, cognitive, language, adaptive skills and ASD symptomatology. The numbers increased only marginally when we examined developmental and cognitive assessments separately, with respondents (%) completing a developmental assessment in addition to measures of language, adaptive skills and ASD symptoms, and (%) completing a cognitive assessment in addition to these other measures. Taking the profession-specific assessments separately revealed that Psychologists (%) administered cognitive and adaptive assessments in addition to measures of ASD symptomatology, and Speech Pathologists (%) administered language assessments in addition to measures of ASD symptomatology. [Insert Table about here] To account for clinicians who may review the results of assessments that are administered by other disciplines, we also asked participants to indicate whether they review assessment results. Sixty-seven (%) respondents reported that they review assessment results. There were no differences in the proportion of respondents from each profession, χ (, N = ) =., p =., Φ =., or state, χ (, N = ) =., p =.0, Φ =. who review the results of assessments. Finally, we investigated whether respondents who do not regularly administer BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

12 Page of BMJ Open assessments (i.e. in less than 0% of assessments), review assessment results instead. Six of the respondents (%) who do not regularly administer assessments always review assessment results. A further respondents (%) who do not regularly administer standardized assessments often review these results of assessments that have been administered in other settings. Two respondents, both sole practitioners, reported that they do not administer standardized assessments in diagnostic evaluations for ASD. These respondents reported that they do not administer standardized measures because they are not part of everyday practice, or because they have already been administered at another service. In addition, one respondent reported that the standardized measures are not required because diagnostic decision-making is outlined in the DSM-. Facing uncertainty in diagnosis. Forty-seven respondents (%) reported that they make provisional ASD diagnoses when faced with diagnostic uncertainty. There was no difference in the proportion of provisional diagnoses between the private and public settings, χ (, N = ) =., p =., Φ =., or across the states, χ (, N = ) =., p =.0, Φ =.. Of the respondents who make provisional diagnoses, (%) reported that this label is rarely used, with the remaining (%) and (%) reporting that provisional diagnoses are given occasionally and sometimes respectively. Provisional diagnoses were reportedly given when individuals demonstrated subthreshold symptoms, were very young, or would benefit from intervention. Thirty-nine respondents (%) reported that they re-assess individuals with provisional diagnoses within a mean of months (SD =. months). Sixteen respondents (%) reported that they have diagnosed ASD when the person did not meet full criteria for the condition. Fifteen of these respondents (%) reported that this has rarely occurred (less than % of their assessments), with the remaining respondents indicating that it has been occasional (about 0% of assessments). While there was no significant difference in the proportion of overdiagnosis coming from each state, χ (, N = ) =., p =., Φ =., a significantly higher proportion of respondents who made a diagnosis when the individual did not meet criteria came from the private (%) relative to the public (%) sector, χ (, N = ) =.0, p =.0, Φ =.. When asked about the reasons for making the ASD diagnosis, (%) clinicians reported that they thought that the individual did have ASD, but that the assessment did not accurately reveal the individual s actual diagnostic status. Other commonly BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

13 Page of reported reasons for the diagnosis were to ensure that the child could access early intervention (n = ), school support (n = ) or disability services (n = ). Discussion This study investigated the diagnostic practices for ASD across Australia. The results revealed inconsistencies in ASD assessment practices across the states, and between the private and public service settings. In addition, some clinicians in Australia may not be practicing in a manner that is consistent with international best practice guidelines (e.g., NICE, ) or statements from Australian professional bodies (e.g. Silove et al., 0) for ASD assessment and diagnosis. The current findings are consistent with the results reported by Randall et al. (), who found that only a minority of Australian paediatricians follow current recommendations for diagnosing ASD. Comprehensive diagnostic assessments that comprise all of recommended elements are lengthy and expensive, so it is possible that the time required to administer standardized assessments of ASD symptomatology in addition to conducting observations of the individual across settings is prohibitive for practitioners. A small proportion of respondents (%) reported that they have diagnosed ASD when a person does not meet criteria for the disorder. This was more likely to happen in the private sector than in the public sector. The reasons for making this diagnosis included the assessment did not adequately reveal the actual diagnostic status or to ensure that the person could access early intervention, support at school or access other disability services. These findings are consistent with previous research that has investigated the diagnostic practices of clinicians in Queensland, the United States and the United Kingdom (Rushton et al., 0; Rogers et al., ; Skellern et al., 0). The results of these previous studies have indicated that up to % of participating health professionals had increased the level of diagnosis or severity, most commonly because of a lack of diagnostic certainty, but also to ensure that the individual could access funding, educational support or other services. The intentional ascription of an inaccurate diagnosis to facilitate access to services may contribute to the increased diagnostic rates over time. Indeed, Nassar et al. (0) found that the increased incidence of ASDs in WA was related BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

14 Page of BMJ Open to changes in diagnostic practices and service provision in this state. These findings highlight the complexity of ASD diagnosis and the challenges associated with funding being designated according to diagnosis rather than need. While the sample size in this study was small, the number of respondents was similar to that reported by Rogers et al. (), who included a sample of participants in a recent survey of diagnostic practices in the UK. Although our sample had representatives from all states and relevant professions, the numbers were not consistent across categories. In addition, respondents in this study were self-selected, perhaps because of a strong interest in good diagnostic standards, so the results may not represent the broader population of diagnosticians in Australia. Notwithstanding this, the findings suggest the need for the development of national standards in ASD diagnostic practices with evaluation of the implementation of these standards. Conclusion This research is the first study to investigate diagnostic practices for a range of professionals across Australia. While some Australian states have established rigorous standards for ASD assessments, there is currently no minimal national standard for ASD diagnosis. The variability in diagnostic practices of ASD across the nation, as well as assessments that are inconsistent with best practice guidelines may contribute to poor quality assessments, possible delayed diagnosis and access to intervention services. Conversely, assessments that more closely resemble current clinical guidelines for ASD diagnosis may be associated with longer wait list times. In addition, findings regarding the possible over-diagnosis of ASD have implications for service delivery, particularly when funding and service provision is determined based on diagnosis. These findings highlight the need for a consistent national standard in ASD diagnosis, to ensure an equitable process for families and individuals with ASD. BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

15 Page of Acknowledgements The authors also acknowledge the health professionals who dedicated their time to participate in this research. Funding The authors acknowledge the financial support of the Cooperative Research Centre for Living with Autism (Autism CRC), established and supported under the Australian Government's Cooperative Research Centres Program and the Department of Social Services. Contributors LT designed and administered the survey for health professionals, was involved in data analysis and interpretation and wrote and reviewed the manuscript. VE, MM, SM, JP, LQ, TS, KW and AW were involved in study design, including survey design and these authors also contributed to the preparation of the manuscript. All authors contributed to participant recruitment. Ethics approval This study was approved by the ethics committee of the University of Western Australia (Ref RA///). Data Sharing Statement No additional data available. BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

16 Page of BMJ Open Number of services months - months - months - months months Private Public Figure. Total number of public and private services which have wait-list periods of less than three months to over months. BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

17 Page of Table. Number of respondents from each state or territory of Australia, categorized by profession. Australian State/Territory ACT NSW NT Qld SA Tas Vic WA Total General Practice Paediatrics - Psychiatry Psychology - Speech Pathology - Occupational Therapy Other* Total 0 0 *Comprising one Manager (TAS), Researcher (QLD), Dual paediatrics/psychiatry (VIC), Autism consultant/researcher (SA) and not specified (NSW) BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

18 Page of BMJ Open Table. Proportion of respondents (N = ) from each discipline who administer developmental, cognitive, language, adaptive or ASD assessment measures. Respondents were given a list of assessments that fitted within each category, but were also able to specify other measures that they administer. Example assessments within each category are described at the foot of the table. Paediatrics (N = ) Psychiatry (N = ) Psychology (N = ) Speech Pathology (N = ) OT (N = ) Other (N = ) Developmental Cognitive Language Adaptive ASD.%.%.%.0%.% %.%.% 0.%.%.% 0.%.00%.00%.00%.00%.00%.%.%.%.%.% 0% 0 0 0% 0% Developmental Assessments: Griffiths, Bayley, Mullen Cognitive Assessments: WPPSI, WISC, WAIS, Leiter, UNIT, WNV Language Assessments: CELF, CASL, CCC-, CC-A, PLS Adaptive Assessments: VABS, ABAS, ABS, Scales of Independent Behaviour ASD Assessments: ADOS, ADI, Di, DISCO, CARS, M-CHAT, SCQ, ASSQ, ASRS, CAST, SRS Other Assessments: Connor s, CBCL, SDQ, BRIEF BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

19 Page of References Anagnostou, E., Zwaigenbaum, L., Szatmari, P., Fombonne, E., Fernandez, B. A., Woodbury- Smith, M., Scherer, S. W. (). Autism spectrum disorder: Advances in evidencebased practice. Canadian Medical Journal,, 0-. American Psychiatric Association. (). Diagnostic and statistical manual of mental disorders ( th ed.). Washington, DC: Author. Australian Advisory Board on Autism Spectrum Disorders. (0, July ). Position paper on the diagnosis and assessment of Autism Spectrum Disorders in Australia. Retrieved from %July%%Final.pdf. Australian Government. (, January ). Disability and Carers: Helping Children with Autism (HCWA) Eligbility Retrieved //,, from Australian Institute of Health and Welfare. (0, September). Rural, Regional and Remote Health. Indicators of Health System Performance Retrieved //,, from Baird, G., Cass, H., & Slonims, V. (0). Diagnosis of autism. British Medical Journal,, -. Cox, A., Klein, K., Charman, T., Baird, G., Baron-Cohen, S., Swettenham, J., Drew, A., & Wheelwright, S. (). Autism spectrum disorders at and months of age: Stability of clinical and ADI-R diagnosis. Journal of Child Psychology and Psychiatry, 0, -. Crane, L., Chester, J., Goddard, L., Henry, L., & Hill, E. L. (). Experiences of autism diagnosis: a survey of over 00 parents in the United Kingdom. Autism, Dover, C. J., & Le Couter, A. (0). How to diagnose autism. Archives of Disease in Childhood,, 0-. Eaves, L. C., & Ho, H. H. (0). The very early identification of autism: Outcome to age ½ -. Journal of Autism and Developmental Disorders,, -. BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

20 Page of BMJ Open Fenske, E. C., Zalenski, S., Krantz, P. J., McClannahan, L. E. (). Age at intervention and treatment outcome for autistic children in a comprehensive intervention program. Analysis and Intervention in Developmental Disabilities,, -. Glasson, E. J., MacDermott, S., Dixon, G., Cook, H., Maley-Berg, A., & Wray, J. (0). Management of assessments and diagnoses for children with autism spectrum disorders: the Western Australian model. Medical Journal of Australia,, -. Granpeesheh, D., Dixon, D. R., Tarbox, J., Kaplan, A. M., & Wilke, A. E. (0). The effects of age and treatment intensity on behavioural intervention outcomes for children with autism spectrum disorders. Research in Autism Spectrum Disorders,, -. Horlin, C., Falkmer, M., Parsons, R., Albrecht, M. A., & Falkmer, T. (). The cost of Autism Spectrum Disorders. PLOS One, DOI:./journal.pone.0. Huerta, M., & Lord, C. (). Diagnostic evaluation of Autism Spectrum Disorders. Pediatric Clinics of North America,, -. Knapp, M., Romeo, R., & Beecham, J. (0). Economic cost of autism in the UK. Autism,, -. Leveratt, M. (0). Rural and remote Australia equity of access to health care services. The Australian Health Consumer,, -. Lord., C., Rutter, M., DiLavore, P., Risi, S., Gotham, K., & Bishop, S. (). Autism Diagnostic Observation Schedule, Second Edition (ADOS-). Torrance, CA: Western Psychological Services. Magiati, I., Tay, X. W., & Howling, P. (). Early comprehensive behvaiourally based interventions for children with autism spectrum disorders: a summary of findings from recent reviews and meta-analyses. Neuropsychiatry,, -0. Moore, V., & Goodson, S. (0). How well does early diagnosis of autism stand the test of time? Autism,, -. Nassar, N., Dixon, G., Bourke, J., Bower, C., Glasson, E., de Klerk, N., & Leonard, H. (0). Autism spectrum disorders in young children: effect of changes in diagnostic practices. International Journal of Epidemiology,, -. NICE. (). Autism in under s: recognition, referral and diagnosis. Retrieved from BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

21 Page of Ozonoff, S., Goodlin-Jones, B. L., & Solomon, M. (0). Evidence-based assessment of autism spectrum disorders in children and adolescents. Journal of Clinical Child and Adolescent Psychology, (), -0. Ozonoff, S., Iosif, A., Young, G. S., Hepburn, S., Thompson, M., Colombi, C., & Rogers, S. J. (). Onset patterns in autism: Correspondence between home video and parent 0. Prior, M., Roberts, J. M. A., Rodger, S., & Williams, K. (). A review of the research to report. Journal of the American Academy of Child and Adolescent Psychiatry, 0, - identify the most effective models of practice in early intervention for children with autism spectrum disorders. Australian Government Department of Families, Housing, Community Services and Indigenous Affairs, Australia. Available from Randall, M., Albien-Urious, N., Brignell, A., Gulnec, A., Marraffa, C., Silove, N., & Williams, K. (). Diagnosing autism: an Australian paediatric research network survey. Journal of Paediatrics and Child Health,, -. Reichow, B. (). Overview of meta-analyses on early intensive behavioral intervention for young children with autism spectrum disorders. Journal of Autism and Developmental Disorders,, -. Rogers, C. L., Goddard, L., Hill, E. L., Henry, L., & Crane, L. (). Experiences of diagnosing autism spectrum disorder: a survey of professionals in the United Kingdom. Autism,. Rogers, S. J., Estes, A., Lord, C., Vismara, L., Winter, J., Fitzpatrick, A., & Dawson, G. (). Effects of a brief Early Start Denver Model (ESDM)-based parent intervention on toddlers at risk for autism spectrum disorders: a randomized controlled trial. Journal of the American Academy of Child and Adolescent Psychiatry,, -. Rutter, M., LeCouter, A., & Lord, C. (0). Autism Diagnostic Interview, Revised (ADI-R). Torrance, CA: Western Psychological Services. Silove, N., Blackmore, R., Warren, A., Gibbs, V., & Roberts, J. (0, July). A consensus approach for the paediatrician s role in the diagnosis and assessment of autism spectrum BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

22 Page of BMJ Open disorders in Australia. Retrieved from Skellern, C., McDowell, M., & Schluter, P. (0). Diagnosis of autistic spectrum disorders in Queensland: Variations in practice. Journal of Paediatrics and Child Health,, -. Skellern, C., Schluter, P., & McDowell, M. (0). From complexity to category: Responding to diagnostic uncertainties of autistic spectrum disorders. Journal of Paediatics and Child Health,, 0-. Skuse, D., Warrington, R., Biship, D., Chowdhury, U., Lau, J., Mandy, W., & Place, M. (0). The developmental, dimensional and diagnostic interview (di): A novel computerized assessment for autism spectrum disorders. Journal of the American Academy of Child and Adolescent Psychiatry,, -. Stewart, J. R., Vigil, D. C., Ryst, E., & Yang, W. (). Refining best practices for the diagnosis of autism: A comparison between individual healthcare practitioner diagnosis and transdisciplinary assessment. Nevada Journal of Public Health,, Williams, M. E., Atkins, M., & Soles, T. (0). Assessment of Autism in community settings: Discrepancies in classification. Journal of Autism and Developmental Disorders,, 0-. World Health Organization. (). International classification of diseases: Diagnostic criteria for research (th edition). Geneva, Switzerland: Author. BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

23 Page of Appendix A Question category Participants were asked Diagnostic whether they worked in a private or public (hospital, Setting. government or non-government organization) practice setting if their service was located in a metropolitan, regional, rural or remote setting in Australia about the nature of the service, i.e., whether they conduct general developmental assessments or only ASD assessments whether they work as a sole practitioner or as part of a multidisciplinary team. Respondents then described the nature of collaboration within the multidisciplinary team, or with external agencies or professionals. Diagnostic the number and length of assessment sessions they conduct Practice. for ASD assessments whether the assessments include multiple informants, such as parent and teacher, over multiple settings specific details about the assessment measures that they include in diagnostic assessments for ASD. Diagnostic the number assessments that their service had conducted in Outcomes. the months prior to the survey the percentage of the assessments that had resulted in an ASD diagnoses. the frequency of Social (Pragmatic) Communication Disorder diagnoses in their service whether they had ever diagnosed ASD when an individual did not meet diagnostic criteria for the diagnosis. BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

24 DIAGNOSTIC EVALUATION FOR AUTISM SPECTRUM DISORDER: A SURVEY OF HEALTH PROFESSIONALS IN AUSTRALIA Journal: BMJ Open Manuscript ID bmjopen--0.r Article Type: Research Date Submitted by the Author: -Aug- Complete List of Authors: Taylor, Lauren; University of Western Australia, School of Psychology; Cooperative Research Centre for Living with Autism (Autism CRC) Eapen, Valsamma; South Western Sydney Local Health District, ICAMHS; University of New South Wales, School of Psychiatry Maybery, Murray; University of Western Australia, School of Psychology; Cooperative Research Centre for Living with Autism (Autism CRC) Midford, Suzanne; Western Australian Autism Diagnostician's Forum Paynter, Jessica; The AEIOU Foundation, Research Department Quarmby, Lyndsay; University of Tasmania, Centre for Rural Health Smith, Timothy; Disability Services Commission Williams, Katrina; University of Melbourne, Developmental Medicine Whitehouse, Andrew; Telethon Kids' Institute; Cooperative Research Centre for Living with Autism (Autism CRC) <b>primary Subject Heading</b>: Health policy Secondary Subject Heading: Paediatrics, Health policy Keywords: Autism Spectrum Disorder, Diagnosis, Health policy < HEALTH SERVICES ADMINISTRATION & MANAGEMENT BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

25 Page of BMJ Open DIAGNOSTIC EVALUATION FOR AUTISM SPECTRUM DISORDER: A SURVEY OF HEALTH PROFESSIONALS IN AUSTRALIA Lauren J. Taylor,,, Valsamma Eapen,, Murray T. Maybery,, Sue Midford, Jessica Paynter,,, Lyndsay Quarmby, Timothy Smith,, Katrina Williams,,,, Andrew J. O. Whitehouse,. School of Psychology, The University of Western Australia, Australia. University of New South Wales, New South Wales, Australia. Western Australian Autism Diagnostician s Forum, Western Australia, Australia. Research Department, AEIOU Foundation, Queensland, Australia. Centre for Rural Health, University of Tasmania, Australia. Disability Services Commission, Western Australia, Australia. Department of Paediatrics, University of Melbourne, Melbourne, Australia. Developmental Medicine, Royal Children s Hospital, Melbourne, Australia. Murdoch Children s Research Institute, Melbourne, Australia. Telethon Kids Institute, The University of Western Australia, Australia. Cooperative Research Centre for Living with Autism (Autism CRC), Brisbane, Queensland, Australia. School of Applied Psychology, Griffith University, Gold Coast, Queensland, Australia *Corresponding Author: Word count: 00 (all inclusive) Lauren Taylor School of Psychology, Henry Wellcome Building Institute of Psychiatry, Psychology and Neuroscience King s College London De Crespigny Park London SE AF lauren.taylor@kcl.ac.uk + (0) 00 BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

26 Page of Abstract Objectives: There is currently no agreed Australian standard for diagnosis of Autism Spectrum Disorder (ASD) even though there are specific diagnostic services available. We suspected inconsistent diagnostic practices for health professionals in Australia and aimed to assess these practices across the nation by surveying all relevant professional groups. Design: In this study, we completed a survey of health professionals whose clinical practice includes participating in the diagnostic process for ASD in Australia. Participants completed an online questionnaire which included questions about their diagnostic setting, diagnostic practice and diagnostic outcomes in -. Participants: Participants covered a range of disciplines including paediatrics, psychiatry, psychology, speech pathology and occupational therapy. All states and territories of Australia were represented. Setting: Participants came from a range of service settings which included hospitals, nongovernment organisations, publicly funded diagnostic services and private practice. Results: There was variability in diagnostic practices for ASD in Australia. While some clinicians work within a multidisciplinary assessment team, others practice independently and rarely collaborate with other clinicians to make a diagnostic decision. Only half of the respondents reported that they include a standardised objective assessment tool such as the Autism Diagnostic Observation Schedule in ASD assessments, and one third indicated that they do not include measures of development, cognition and language in assessments where ASD is suspected. Conclusions: Reported practice of some professionals in Australia may not be consistent with international best practice guidelines for ASD diagnosis. These findings highlight the need for a minimum national standard for ASD diagnosis throughout Australia that ensures best practice regardless of the type of setting in which the service is provided. Key Words: Autism Spectrum Disorder; Diagnosis; Australia BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

27 Page of BMJ Open Strengths and Limitations of this study This is the first national study to investigate the diagnostic practices of health professionals from different disciplines across Australia. While the study included clinicians from a range of professional backgrounds, there were an unequal number of respondents from each professional group. Respondents were self-selected and may be committed to high standards of clinical practice. BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.

28 Page of DIAGNOSTIC EVALUATION FOR AUTISM SPECTRUM DISORDER: A SURVEY OF HEALTH PROFESSIONALS IN AUSTRALIA In the absence of biomarkers, diagnosis of Autism Spectrum Disorder (ASD) is based on the behavioural presentation of an individual. The gold standard in ASD diagnosis is a best estimate clinical diagnosis which is determined in accordance with current diagnostic classification systems and following rigorous assessment practices. There is general consensus that a rigorous diagnostic assessment for ASD would consist of a physical examination, hearing test, child observation and parent interview which includes a full developmental history (NICE, ). Best-practice ASD assessments are more comprehensive, and also comprise standardised developmental or cognitive testing, language assessment and information from more than one setting, ideally from a source other than the parent or carer who has been interviewed [-]. Rigorous assessments enhance the accuracy of diagnoses and provide information about an individual s strengths and difficulties which is important for intervention planning. Despite the internationally recognised best practice guidelines for ASD diagnosis [], and position statements from professional bodies [-] Australia does not have a national standard for ASD diagnosis. In addition, health services are governed on a state or territory basis, rather than a national level. While in some jurisdictions, eligibility for publicly-funded intervention for children with ASD requires a diagnosis made by a multidisciplinary team comprising a medical professional, psychologist and speech pathologist, other states have less stringent criteria, requiring only a pediatrician or psychiatrist. Furthermore, eligibility for funding from the Helping Children with Autism funding package is determined following a conclusive ASD diagnosis which can be provided by a single paediatrician or psychiatrist []. Identifying ASD accurately and early is essential given that state and federal funding for early intervention is based on a formal diagnosis made before a child turns seven []. An inaccurate diagnosis may mean that children are not eligible for early intervention which contains elements that specifically focus on areas of difficulty in ASD []. Alternatively, children who are misdiagnosed with ASD may access services that are not relevant or effective for their areas of difficulty thereby wasting resources. In addition, it is well established that early intervention improves outcomes for children with ASD [-] and that children who start BMJ Open: first published as./bmjopen--0 on September. Downloaded from on June by guest. Protected by copyright.