The most recent estimates of the prevalence rates of Autism Spectrum Disorder reveal that 1 in 68 children in the US are diagnosed with ASD. However, although the awareness of ASD has been increasing around the world, most studies of the prevalence rates and diagnosis of ASD originate in developed countries, and little is known about the situation in developing countries. Indonesia is the fourth most populated country in the world. However, as is the case in most developing countries, disability still receives limited attention from the Indonesian Government. In terms of ASD, there is no recent estimate of the prevalence rate of ASD in Indonesia following the estimates released 22 years ago which suggested that 1 in 833 children in Indonesia were being as diagnosed with ASD. Currently studies on ASD are still lacking and almost 500 cities and regencies in Indonesia are unable to identify and provide appropriate support services for people with ASD.
As a starting point to understanding the situation relating to ASD in developing countries, the first study in this thesis aimed to investigate the application of best practice guidelines in Indonesia. A survey was developed and undertaken with 67 practitioners with experience in assessing ASD. It was found that, similar to situations in developed countries, the three best practice components relating to ASD diagnosis were challenging to apply in the Indonesian context. Further, having more validated and culturally sensitive tools to assess ASD in Indonesian language was found to be one of the crucial needs of ASD specialists in Indonesia.
As a response to this finding, an Indonesian version of ADEC (ADEC-IND) was developed and evaluated for its psychometric properties and cultural appropriateness. The ADEC is an observation tool that has been shown to be effective in detecting ASD in children as young as 12 months. The tool has been validated within Australian and in Mexican children. In comparison to the gold standard measurement tools, the use of ADEC is more affordable, less time consuming in administration, and does not require lengthy and expensive training for its use. Considering these benefits and as a response to the first study results, the second and third studies that comprise this thesis were conducted in order to translate and validate the use of ADEC within the Indonesian context.
The ADEC was translated into the Indonesian language and then pilot tested with eight Indonesian children (Mage = 31.8 months, SD = 11.36) in Brisbane and Melbourne. In the translation process, after being translated, the first Indonesian version of ADEC (ADEC-IND) was reviewed independently by two reviewers and a revised draft was made based on the reviewers’ feedback. Subsequently, the revised draft was then pilot tested with each testing session videotaped and given an English subtitle. Each participant was tested using ADEC-IND and their parents interviewed using the ADI-R. All of the sessions were videotaped and given English subtitles. The study found that the revised and translated draft of ADEC-IND is ready for use in a large scale study, as the participants in the pilot study had no problem in understanding the instructions of ADEC-IND, and no difficulties were experienced with either the implementation or scoring.
Following the pilot testing and review, the revised version of ADEC-IND was tested with 82 children in Indonesia. The children were aged between 14 and 72 months (M=45.23 months, SD=14.51) who were classified within three diagnostic groups (typical developing children, children with ASD, and children with other disabilities). The participants were recruited from clinics and schools in five major cities in Indonesia (Jakarta, Bogor, Depok, Tangerang, and Bekasi). Similar to the pilot study, the children were assessed using the ADEC-IND and the parents were interviewed using the ADI-R. All sessions were videotaped. For investigating the inter-rater reliability, fifty videotaped sessions were given English subtitles and re-scored by a second assessor who was blind to the original scores, using the English version of the ADEC. The results showed that ADEC-IND possessed good sensitivity (.92 to .96), good specificity (.85 to .92), and high inter-rater reliability (r = .94, p < .001). ADEC-IND also showed good concurrent validity and good agreement (82.92%) with the ADI-R in classifying children into ASD and non-ASD groups. The implications of these findings are discussed in relation to the assessment and diagnosis of ASD in Indonesia.