Sayyed Ali Samadi has an article at Brain Sciences titled "Overview of Services for Autism Spectrum Disorders (ASD) in Low- and Middle-Income Countries (LMICs) and among Immigrants and Minority Groups in High-Income Countries (HICs)"
Autism spectrum disorder (ASD) prevalence is rising  at different paces. The reported prevalence currently lies between 0.9% and 1.5% . In affluent and high-income countries, a higher speed is reported compared to a slower pace in developing countries . A recent worldwide ASD prevalence estimate of 0.6% falls far below estimates for Western developed societies. This reported difference probably reflects an inability to diagnose due to the shortage of available diagnostic services rather than a natural worldwide variation in the incidence of ASD in its different forms . There are various contributing factors to the reported difference. It reflects inequality in broadening the diagnosis services and different levels of awareness among countries and multiple degrees of endeavor for identification among children primarily. Hence, the increasing international wealth of information on ASD is based mainly on numerous studies conducted in developed, affluent countries . As de Leeuw et al.  indicated, “Autism research is heavily skewed towards western high-income countries”.
More attention should be considered to the presence of similarities and differences in the representation and the influence of ASD in different world regions and between different cultures and minority groups. Still, the available wealth of data remains limited in low-and-middle-income countries (LMICs) and among immigrants and minority groups in high-income countries (HICs). In many ways, there is considerable overlap between the situation for individuals with ASD in LMICs and HICs . There are similar challenges for this group of individuals and their family members and caregivers in both country groups. Hence, there are additional cultural, political, and economic challenges pertaining to LMICs . There are different aspects of ASD that have been understudied, and investigating their impacts on particular groups of individuals is missed in LMICs and HICs. It seems that healthcare policymakers were not entirely convinced to consider these research aspects and allocate strategies and resources for them. There are various reasons for this neglect; still, factors such as lack of suitable instruments for detection and diagnosis, lower levels of awareness and practiced stigma affecting demand for ASD caregiving and the dominance of specialist models for diagnosis and treatment, and finally, the high cost of researching ASD contributed to this imbalance in LMICs . There are understudied groups in the ASD population, such as groups with ASD and other developmental disabilities , and aspects of the life of individuals with ASD, such as their sexual development  in HICs.