Autism Spectrum Disorder

Autism Spectrum Disorder is a syndrome characterized by a lack of communication, behavior, stereotypes, and rituals (Eikeseth, 2009). Initially thought to be produced by the environment, the sickness was recently determined to be a component of the severe neurodevelopmental syndrome (Niklasson, Rasmussen, Oskarsdottir, & Gillberg, 2009). ASD begins at birth and can be diagnosed at the age of 18 months. In a considerable majority of cases, the effects of ASD symptoms last a lifetime. ASD is associated with differences in impulsivity, psychopathology, and challenging behaviors, which are reported in greater numbers than in the general population. The inconsistencies make it very challenging for the individuals with ASD to live an independent life. In this paper, the question whether the increasing ASD prevalence is a result of the actual rise in the prevalence or because of other factors is answered.

ASD Prevalence

For many decades, autism prevalence and incidences has been increasing. However, it is not clear whether this increase is due to the broadened diagnostic approaches, better ascertainment, increased awareness, expanding the definition, increase in the incidence or a combination of these factors (Baird & Charman, 2006). Most recent scientific reports indicate the increasing prevalence of ASD although some attribute this trend to other factors. Autism has been observed to affect both children and adults even though the widespread presence in these populations is different. The increasing ASD commonness in UK and US has sparked fears of an autism epidemic amongst researchers since they started tracking it in the year 2000. Most of the concerns are embedded in the fact that the condition is affecting both old and young populations. However, the topic remains controversial due to its close characteristics to the related cognitive impairments (Attention Deficit Hyperactive Disorder).

Currently, there are heated debates over the increasing prevalence of ASD. Previously believed to be rare, many people are being diagnosed with this condition. According to Matson and Kozlowski (2010), every 10 in 10000 persons have ASD. The current approximations indicate that there is an increased rate of 110% in every 10,000 persons. We are certain that the percentage of people diagnosed with ASD continue increasing. However, there are controversies as to what causes the rise in the commonness of autism. Many researchers attribute the growth to the enhanced diagnostic criteria, new assessment instruments, the use of distinct research methodologies, inaccurate diagnosis, cultural diversities, an increasing level of awareness. Nevertheless, the details provided in these categories of factors complicate the general perception that includes autism regression and diagnostic substitution. To understand some of the reasons that researchers have provided about ASD, we will look at these factors one at a time.

Diagnostic Assessment and Criteria

The changes in diagnostic criteria are one of the factors that researchers attribute to the rise of ASD (Waldman, Nicholson, Adilov, & Williams, 2008). The diagnostic criteria for ASD were initially guided by the Diagnostic and Statistic Manual of Mental Disorders, Third Edition (DSM III) (American Psychiatric Association, 1987). Many classifications in this criteria embodied groupings such as ASD, symptoms number required for a diagnosis, and the age of the individual. Compared with the International Classification of Diseases series (ICD-10), the DSM criteria relied on the symptoms to determine whether an individual was to undergo the diagnosis. ICD-10 was used to classify mental illnesses to determine the most unusual symptoms of ASD. Luckily, the criteria that were initiated for DSM-IV and DSM-IV-TR have been found to merge with the ICD-10, leading to the diagnoses that are more consistent globally. Therefore, the deficits in communication and socialisation are merged into one group of symptoms endorsing the other three traits (deficiencies in non-verbal and verbal communication, the inadequacy of social reciprocity, and the incapacity of developing and maintaining developmental relevant relationships) significant during ASD diagnosis.

Satisfactory diagnosis requires that the individuals must meet the following benchmarks: three repetitive and restricted habits/behaviours, activities criteria, and interests; categorised sensory, motor, verbal, or other habits; compliance with ritualised behaviour patterns; and the controlling interests. Changes in these criteria affect the prevalence of ASD. Additionally, the universal idea that comprises ASD has been extended to constitute the Asperger Syndrome, an individual’s lifespan, and the individual having profound and severe intellectual disabilities. Therefore, the continually changing ASD diagnostic standards and the evaluation of the mentioned discrepancies varies with time. The alterations in the instruments of diagnoses contribute to the marked variances in incidences across different studies. In light of these changes, we should understand that how ASD is defined and the diagnostic criteria used significantly determine how the prevalence is evaluated.

Inaccurate Diagnosis

Inaccurate diagnosis is believed to result in the rise in ASD commonness. For instance, Barbaresi, Colligan, Weaver, and Katusic (2009) discovered a 22.1% rise in the clinically determined ASD diagnoses between 1995 and 1997 compared to evidence/study-based ASD diagnoses that showed an increase of 8.2%. Clinical diagnosis is made through a brief observation using ICD and DSM procedures and not with regular tests. Nevertheless, even with the application of tests, there is a wide variation depending on the type of tests used and the respondent's characteristics. Moreover, different clinicians such as clinical and school psychologists, psychiatrists, and neurologists can evaluate the individuals with ASD. Due to the varying level of experience and skills, different clinicians may administer various levels of evaluations that may arrive at different diagnostic outcomes. In such a case, there may be inconsistent diagnoses leading to the justification of diverse ASD prevalence thresholds. Additionally, clinicians using research criteria as their diagnostic approaches would heavily rely on the homogenous procedures that have standard tests battery that has been carried out by experts in ASD. In such cases, diagnoses based on research could be more accurate compared to other less accurate diagnostic criteria that cause an increase in reported rates of ASD and thus an increased prevalence. Furthermore, a child with a mental disability or ASD has an increased tendency to receive a mental disability versus an ASD diagnosis compared to previous approaches (Posserud, Lundervold, Lie, & Gillberg, 2009). This means that more attention and resources are pulled towards ASD diagnosis that further accounts to the rise of ASD prevalence rates.

Research Methodology

ASD prevalence rate estimations can be obtained using data from retrospective accounts, registers, whole-region surveys and interviews through the telephone. Evidently, variations between study methodologies result to distinctions in the ASD prevalence rates. Fombonne, (2015) stated that current research concerning ASD prevalence rates is not enough evidence for or against the increasing commonness because different methods have been employed on individuals under assessment. In a recent CDC’s study, the only evidence that some researchers use while accounting for the increasing ubuquity is medical and education records (Center for Disease Control and Prevention, 2009). The differences in research methods result in higher ASD incidence levels in areas that had both education and medical records available. Henceforth, if such differences in methodologies occur in a single study, the prevalence rate findings will be different. Lastly, the use of autistic regression can be used for the assessment of children such that if the data covers ASD children below 13 years, the prevalence rate is likely to increase in the future.

Environmental Components

The environment is thought to influence the prevalence rates of ASD. For instance, the MMR vaccines and the current findings indicate that occasional irritation in the intestines of eleven of twelve cohorts under assessment were likely to result in delays in the development. Whereas the majority of researchers claim that physiological conditions have the chance to cause autism, authors such as Matson and Kozlowski (2010) argue that MMR vaccine results to behavioural disorders that constitute encephalitis and disintegrative psychosis. Taylor et al. (2012) refuted such claims withdrawing any links between the condition and the vaccine. In addition, there are many improvements in neonatal and perinatal cares, which results in greater survival rates for premature newborns. These new-borns are shown to have greater risks for neurodevelopmental disorders, including ASD (Johnson et al., 2010). The risk factors associated with perinatal care and the increased rates of neonatal hospitalisation are seen as the possible causes of increased prevalence of ASD. Some researchers claim that hurricanes and tropical storms cause ASD as they tend to disrupt development during the critical gestation period. Finally, there are claims that toxic metals and chemicals can cause ASD. However, these environmental causes have not been validated to date.

Cultural Factors

Kamer, Zohar, Youngmann, Diamond, Inbar, and Senecky (2004) discovered that there was an increase in the rates of ASD in the US. This was meant to conclude that prevalence rates were more in developed countries compared to developing nations. This was true since there was a clear distinction between ASD children in Israel and those in Ethiopia. Therefore, social factors and acculturation played a critical role when identifying ASD children, and therefore affected the general prevalence rates in those countries. According to other researchers, ethnic bias accounts for diagnostic differences on ASD prevalence rates. Sun and Allison (2010) suggested that such ideas concerning ASD were un-heard in the Eastern countries. They undertook reviews of epidemiological studies, which have been carried out from 1971 to 2008 in Asia (Iran, China, Israel, Japan, Taiwan and Indonesia). They discovered significant differences across these countries about ASD prevalence rates which were seen to increase with time. Therefore, inclining to Kamer et al. (2004), the prevalence rates differences are determined across ethnic groups, countries or groups of countries.

Awareness

This is a critical factor when it comes to an understanding of the increasing prevalence rates. According to Ouellette-Kuntz et al. (2007), the reason for the rising presence of ASD is caused by the continued increase in the ASD awareness. The acknowledgement arises as a result of the constant discussions of the condition in the media, which often centers on the vaccinations that trigger such disorders. Parents have become more aware of the condition and can identify whether their children have the condition, hence, seek medical attention. Therefore, an increased level of awareness amongst parents makes them take their children to be assessed even though they might not have done that before. Moreover, due to services simultaneously causing an increase and improvement in awareness, the ASD diagnoses are more acceptable to both clinicians and parents increasing the prevalence rates. Such discoveries ensure that the condition is nor misdiagnosed or under diagnosed.

For several decades, ASD reported cases have been steady. Therefore, it seems that there will be no end to the insights regarding the increasing number of individuals with ASD. Several researchers attribute the difference in prevalence rates to the variation of the diagnostic criteria used and the efforts put to prioritise ASD during assessment or multiple diagnoses. Some researchers contend presence of numerous factors that determine the increased prevalence. Others concentrate on a few and not all considerations when determining prevalence rates. The diagnosis at a young age broadened diagnostic criteria, and improved efficacy of case ascertainment are the fundamental elements that have resulted in the observed increase in ASD prevalence rates. However, there is a need for more research to test and prove these hypotheses. Nevertheless, despite the inadequacy of solid retorts about the high ASD incidence rates, several thoughts can be provided basing on the existing works.

The present ASD prevalence rates are higher than the ones found in the previous studies. Nonetheless, portions of these documented evidence showing the rise can be coined to increasing prevalence rates. Therefore, it is not by coincidence that the use of distinct diagnostic criteria makes researchers come up with different numbers. Compared to previous descriptions the frequent relative changes in the diagnostic criteria remains at the core of the observed increase in ASD prevalence rates. This means that we cannot compare current findings with previous findings that indicated lower prevalence rates. Such differences may have been the cause of inaccurate diagnosis that appeared in previous studies. Consequently, in the absence of control measures in observing changes in any particular diagnostic criteria, experts seem to imply that researchers are in no position to make claims that increases are being observed. Furthermore, there are explosions at the media concerning ASD treatment, assessment, and awareness. With such enhanced awareness, improved testing and assessment resources have been developed and can be applied to children as young as one year. Ultimately, many parents are having their children being assessed which is contrary to what they would have done without awareness.

Conclusion

Even though the substantial changes in prevalence rates, cultural factors, distinct research methods, and environmental factors played a critical role in increasing prevalence of ASD in the present times, the diagnostic criteria variations and enhanced ASD attentiveness have robust implications in the study of ASD. Even though differences in research methods are stated in many studies, they cannot specifically apply for ASD. This means that it is unlikely that such a factor would lead to the increase in the prevalence rates. Additionally, cultural elements can be utilised in explaining variation across different cultures and regions globally; they are insufficient to justify the rise in prevalence rates in ASD. Environmental components lacks in research to understand their influence on the rising ASD prevalence rates.

References

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