Development of ODD and CD symptoms in ASD Development of Oppositional Defiant Disorder and Conduct Disorder Symptoms in Autism Spectrum Disorder A.J Gaakeer Tilburg, 12 May 2016 Bachelor Thesis Psychology & Health Department of Developmental Psychology Supervisor: A.M. Scheeren Tilburg University Development of ODD and CD symptoms in ASD Abstract Autism spectrum disorder (ASD) is a common neurodevelopmental disorder and affects 60 to 70 of the 10,000 children. Literature has shown that children and adolescents with ASD often suffer from comorbid psychopathology. Oppositional defiant disorder (ODD) and conduct disorder (CD) are two examples of these comorbid disorders within ASD and both have been examined in the current study. ODD has shown to be a precursor for CD, which has a severe symptomology. There is not much known, about the development of ODD/CD symptoms in ASD, but there is evidence that ODD/CD symptoms within children and adolescents diagnosed with ODD or CD also decrease over time. Therefore, it has been hypothesized in the current study that the symptoms of ODD/CD in children and adolescents diagnosed with ASD decrease over time. The participants of the current study were the parents of 54 children and adolescents diagnosed with ASD. In order to assess these children, the Social Responsiveness Scale (SRS) and the Vragenlijst voor Gedragsproblemen bij Kinderen (VvGK) were used. The results showed a decrease of ASD symptoms and a stability of ODD/CD symptoms over a period of about 4 years. The reason why a decrease in ODD/CD symptoms is not found, might be due because of the involvement of puberty in our sample. So, further research would be necessary to create a better image of the development of ODD and CD in ASD. Keywords: Autism Spectrum Disorder, Oppositional Defiant Disorder, Conduct Disorder, Social Responsiveness Scale, comorbidity, development. Development of ODD and CD symptoms in ASD Introduction Autism spectrum disorder (ASD) is a common neurodevelopmental disorder and affects 60 to 70 of the 10,000 children (Fambonne, 2009). With detailed evidence it has been recognised in the clinical practise that children and adolescents with ASD often suffer from comorbid psychopathology (Gjevik, Eldevik, Fjaeran-Granum, & Sponheim, 2011). Some of these comorbidities are disruptive behaviour disorders, which can contribute to a broad variability in clinical presentation of ASD and have a decreasing effect on the well-being and health of individuals with ASD (Kaat & Lecalavier, 2013). According to the DSM-5, the core symptoms of ASD are severe and pervasive deficits in social communication and interactions and repetitive restrictive behaviours, activities and interests (APA, 2013; Worley & Matson, 2012). Levy, Mandell and Schultz (2009) stated that these core symptoms affect three core domains, namely socialisation, communication and behaviour. Due to these deficits and impairments, individuals with ASD experience delays in their overall development (Williams, Matson, Goldin, & Adams, 2014). One of these impairments within the domain of socialisation are for example an impaired use of non-verbal behaviours to regulate interactions. Furthermore, most individuals with ASD only have a few or no friends and their interaction with peers is delayed. Related to the communication domain, symptoms like delay in verbal language, delayed imaginative and social imitative play, and delayed imaginative and social imitative play are some good examples. The behavioural domain is affected with restricted, stereotyped and repetitive patterns of behaviour and interests. In the current study, a closer look will be taken at the development of the ASD symptoms and the development of the symptoms of some of the comorbid disruptive behaviour disorders in children and adolescents with ASD over time. Since it is known that there are also comorbid disorders that affect children and adolescents with ASD, a lot of research has been done. In a research about these comorbid Development of ODD and CD symptoms in ASD disorders with ASD, it was found that seventy percent of the participants with ASD had at least one comorbid disorder and forty-one percent had two or more (Simonoff, Pickles, Charman, Chandler, Loucas, & Baird, 2008). Some of the most common diagnoses that were found in this research were disorders like social anxiety disorder (29.9%), attentiondeficit/hyperactivity deficit/hyperactivity disorder (ADHD) (28.2%), oppositional defiant disorder (ODD) (28.1%) and conduct disorder (CD) (3.2%). Similarly, comparable results were found in another research (Amr, Raddad, El-Mehesh, Bakr, Sallam, & Amin, 2012). Sixty-three percent of the children with ASD was diagnosed with at least one comorbid disorder and the most common reported disorders were anxiety disorders (58.3%), obsessive compulsive disorder (OCD) (55%), ADHD (31.6%), CD (23.3%) and major depressive disorder (13.3%). In other studies, in which the prevalence of disruptive behaviour disorders, especially ODD and CD, in individuals with ASD was assessed, varying results were found. Leyfer et al. (2006) found comorbidity for disruptive disorders children with autism, namely ADHD (30.6%) and ODD (7%). De Bruin et al. (2007) found a prevalence of 37.2% for ODD and 9.6% for CD, whereas Gjevik et al. (2011) found a prevalence of 4% for ODD and 3% for CD. Mattila et al. (2010), who used the same measure instrument as Gjevik et al. (2011), surprisingly found a prevalence of 16% for ODD and 2% for CD. Gadow et al. (2004) found a prevalence 13.5% for ODD and 1.5% for CD, but a year later they did a comparable research and found the prevalence rate had risen to 27.6% for ODD and 7.1% for CD (Gadow, DeVincent, Pemeroy & Azizian, 2005). In a review article about disruptive behaviour disorders and ASD it was found that for children with ASD the prevalence estimates for ODD vary between the 4% and 37% and for CD vary between the 1% and 10% (Kaat & Lecavalier, 2013). In this review they compared the results of seven different studies, like the studies mentioned above, about the prevalence of disruptive behaviour disorders in children and adolescents with ASD. A combined prevalence rate over those seven studies was formed, Development of ODD and CD symptoms in ASD which gave a prevalence rate of 21% for ODD and 5% for CD. The prevalence of ODD in ASD is therefore higher than the prevalence of ODD in the general population (APA, 2000). Thus, there seems to be clear evidence that ASD is often related with disruptive behaviour disorder symptoms. Different studies showed similar results and the same comorbid disorders have been associated with ASD. Therefore, is seems urgent to create a better image of the development of disruptive behaviour disorders in children and adolescents with ASD and maybe early detection of those symptoms is possible. The focus in this thesis will lie on the symptoms of ASD and the symptoms of two disruptive behaviour disorders ODD and CD in children and adolescents with ASD. According to the DSM-5 people with ODD have a pattern of angry/irritable mood, argumentative/defiant behaviour or vindictiveness. A child with ODD for example argues a lot with his or her parents, feels very angry, ignores adult rules and may try to annoy other people or blame them for their mistakes (Comer, 2004). CD is a disorder that seems to look like ODD, but with a worse pathological symptomatology. CD is described as a repetitive and persistent pattern of behaviour in which the basic rights of others or major age-appropriate social norms or rules are violated, like aggression to people and animals, destruction of property, deceitfulness or theft and serious violations of rules (APA, 2013; Lindhiem, Bennett, Hipwell, & Pardini, 2015). Therefore, children with CD are a more severe problem than children with ODD. Many of them are suspended from school, put in to foster homes, or locked up in jail. As these children get older, their acts of physical violence may also include rape and sometimes even homicide (APA, 2013). Different causes for CD are mentioned and a number of cases have been linked to genetic factors, traumatic events or very bad parenting or family conflicts (Comer, 2004). However, there are many researchers who believe that ODD is a precursor of CD or conduct problems, when it is regarded along the developmental path of behaviour disorders (Del Valle, Kelley, & Seoanes, 2001; Kann & Hanna, 2000). Development of ODD and CD symptoms in ASD Furthermore, it was hypothesized that inattentive-hyperactive and oppositional behaviour are developmental precursors to conduct problems (Lahey, Van Hulle, Rathouz, Rodgers, Dónofrio, & Waldman, 2009). They found that conduct problems across 8-13 years were independently predicted in a slight degree by both inattentive-hyperactivity and oppositional behaviour. Generally, ODD and CD both have a serious impact on children and their development and therefore further research into the development of ODD and CD and the link with ASD and its development over time might be considerable. The current research will be about the development of the ODD and CD symptoms in children and adolescents with ASD and how their ASD symptoms develop over time. If a better image about the development of ODD/CD and ASD symptoms in children and adolescents with ASD could be created, these children and their parents will be better prepared for the future. Pellicano (2012) found that the autistic symptoms decrease over time. Pellicano examined thirty-seven children diagnosed with an autistic spectrum condition over a period of 3 years. The decrease of symptoms was especially found in the social domain. Furthermore, nineteen percent of the children failed to meet the criteria of the diagnostic instruments after 3 years, due to the substantial changes they have made in their behaviour and social communication. For the developmental course of the symptoms of ODD and CD similar results are found. According to Frick and Loney (1999) the symptoms of ODD and CD on average decrease over time, also without treatment. In a study about the prevalence and development of psychiatric disorders in childhood and adolescence a continuity was found in the prevalence of ODD and CD in children (Costello, Mustillo, Erkanli, Keeler, & Angold, 2003). The stability of the diagnosis of ODD and CD are well described in the literature. If the stability of the CD diagnosis is looked at over a time period of 4 years, about half of the boys between the age of 6 and 13 years who have been diagnosed with CD hold their diagnosis of CD (Lahey, Loeber, Hart, Frick, Applegate, Zhang, et.al., 1995). In a paper Development of ODD and CD symptoms in ASD about ODD and CD it was said that the stability of the diagnosis of ODD seems to be reasonably stable (Loeber, Burke & Pardini, 2009). In this paper a clinical research was discussed, in which boys between the age of 7 and 17 years old annually were assessed for ten years. If there was a diagnosis of ODD at one year, the next year 36% of the boys were again diagnosed with ODD, 27% met the criteria for CD and the rest (37%) was not diagnosed with one of the two diagnoses. According to another research about ODD, two-third of the children or adolescents that were diagnosed with ODD, did not meet the criteria of ODD anymore after three years (Steiner & Remsing, 2007). Similar, Connor (2002) found that circa 67% of the children that are once diagnosed with ODD and received treatment are symptom free after three years, but around the 30% percent of children with ODD will develop CD. This is mostly the case if children with ODD do not get any treatment (Zoccolillo, Pickles, Quinton & Rutter, 1992). When these children with CD become adults, 40 % percent of them will develop an antisocial personality disorder. When children and adolescents who were once diagnosed with ODD are reassessed at the age of 18, 70% cannot be diagnosed with ODD anymore (Nock, Kazdin, Hiripi & Kessler, 2007). Overall, it is found that from year to year the diagnosis of ODD is reasonably stable, but when stability of the diagnosis of ODD and CD is assessed over a longer period of time there can be spoken of a decrease in children who meet the criteria of both diagnoses. Furthermore, there is an overall decrease of symptoms of both ODD and CD over time. However, there is a small group of children who will develop CD or more severe problems over time. It is therefore very urgent to know more about the development of symptoms of ODD and CD in children and adolescents with ASD, because there is not much known if the symptoms of ODD and CD have the same course in children with ASD. Besides the fact that both ASD and ODD/CD are very common disorders within children and adolescents, what makes their comorbidity not very strange, there is something Development of ODD and CD symptoms in ASD else what ASD and ODD/CD might have in common. Accordingly, there is some evidence that speculates that ASD might be linked to offending and criminal behaviour, which is also the case with ODD and CD. It might be possible that criminal behaviour is related to a lack of understanding social cues, something that people with ASD do have problems with (Haskins & Silva, 2006). In addition to this, violent behaviour can occur as a consequence of disruption of routines or stress due to changes in the daily circumstances (Baron-Cohen, 1988). Furthermore, it is also possible that offending or violent behaviour is a causal effect of certain obsessions or defined interests (Barry-Walsh & Mullen, 2004). However, Mouridsen (2012) states in his paper about ASD and offending that there are a few serious crimes about ASD linked to offending, but that there is no strong evidence that people with ASD are more likely to convince a crime. In another research about the prevalence of children and adolescents with ASD in the criminal justice system, they found that children and adolescents with ASD had higher rates of crimes against other people, but lower rates of crimes against property in comparison with children and adolescents without ASD (Cheely, Carpenter, Letourneau, Nicholas, Charles & King, 2012). Mandy, Roughan and Skuse (2004) did a study about oppositionality in ASD and tested the three-way model of ODD in ASD of the DSM-5. Children and adolescents with ASD were assessed and these three dimensions, namely angry and irritable symptoms, argumentative and defiant behaviour and vindictiveness, were associated distinctively with matching psychopathology. In this way, evidence for the validity of the DSM-5 three-way ODD model in ASD was provided. In addition, it has been found that ODD and CD are more common within boys (Maughan, Rowe, Messer, Goodman & Meltzer, 2004). This is in agreement with ASD, because ASD is four times more common in boys than in girls (APA, 2013). So, there is small evidence that children and adolescents with ASD have sometimes been linked to offending and criminal behaviour, which both are very common within ODD and CD, and there is evidence that ASD is comorbid with ODD/CD, Development of ODD and CD symptoms in ASD especially ODD. The prevalence of CD in children and adolescents with ASD is not very big, but it has to be noted that ODD could develop in CD, which could lead to more serious and severe problems. As mentioned previously, it might be urgent to know more about the development of ODD/CD symptoms is children with ASD and that is what thesis will be about. The main question in this thesis is whether the symptoms of ODD and CD in children and adolescents with ASD decrease over time and if their ASD symptoms also decrease over time. Literature already showed that symptoms in children and adolescents diagnosed with ODD and CD decrease over time, but there is not much known about the ODD/CD symptoms within children and adolescents diagnosed with ASD. Although, there is already evidence for the fact that ASD symptoms decrease over time, this will also be checked. So there are two hypotheses, namely (1) ODD and CD symptoms in children and adolescents decrease over time and (2) the ASD symptoms within these children also decrease over time. The urgency of the current research is about creating a better picture of how ODD and CD symptoms will develop within children with ASD. In other words, will these symptoms develop in the same way as they do in children and adolescents without ASD? With little evidence that ASD could be linked to criminal and offending behaviour and clear evidence that ODD and CD are related to those behaviours, this study serves a social purpose. Therefore, it might be important to have a better image of the development of these symptoms, so early detection and treatment of these symptoms could be possible. It has been found that ODD is a precursor of CD, especially when its symptoms are untreated (Zoccolillo, Pickles, Quinton & Rutter, 1992). Furthermore, CD could result in more severe problems when children get older, like rape and theft with assault (APA, 2013) and sometimes when adulthood is reached it could lead to antisocial personality disorder (Zoccolillo, Pickles, Quinton & Rutter, 1992). All of them serious problems, one might want to prevent. Development of ODD and CD symptoms in ASD Method Participants The participants that have been included for the current study are the parents of children diagnosed with ASD, so that information of their children with ASD can be assessed. These participants were a part of a large scale study in the Netherlands about ASD that collected data on two moments of assessment, namely 2009/2010 (T1) & 2013 (T2) (Scheeren et al., 2012 & 2013). These children with ASD had been diagnosed on the basis of the DSM-IV-TR criteria (APA, 2000) by independent psychologist or psychiatrist prior to this study. The parents of children with ASD who participated in 2009/2010 were sent an email in 2013 with an online questionnaire again with questions about their children in order to obtain more information about children and adolescents with ASD. This questionnaire also included a Social Responsiveness Scale (SRS; Constantino & Gruber, 2005) that the parents had to fill in. The SRS, a questionnaire about the severity of autism symptoms, had also been filled in by the parents of children with ASD at T1. The average time between T1 and T2 was 45 months (3.8 years). In the current research, the data of both T1 and T2 are used to test the hypotheses that have been explained in the introduction of this paper. The data of 63 participants of the large scale study have been used for the current study. The 63 participants are, like explained earlier, the parents of 63 children and adolescents with ASD (58 boys; 5 girls). The range of age in years at T1 was between the 7.92 and the 18.92 years, with an average age of 13.23 years. During T2 the range was between 11.58 and 23.33 years, with average age of 17.04 years. Due to missing values in the response of 9 participants, the data of 54 participants is used for the analyses. A reason for this could be that some of the parents who participated at the time of T1, did not respond on the questionnaire that was sent via e-mail during T2 in Development of ODD and CD symptoms in ASD 2013. Table 1 gives a summary of the descriptive statics of the children that are assessed in the current research. Table 1 Descriptive statistics N Minimum Maximum Mean SD Age T1 54 7.92 18.42 12.87 2.94 Age T2 54 11.58 22.42 16.67 2.99 Procedure The participants (children and their parents) that are included in the current study were part of a large scale study from the Netherlands. This large scale study that started in 2009/2010 and involved a full battery of different tests. The parents and children (12 years or older) had to give informed consent. After receiving this the children were individually tested at school. The practitioners of these tests were 14 graduated psychology students. After the children participated in this study, the parents and teachers of the children received a booklet of questionnaires at home. They were asked to fill in those questionnaires concerning his/her child/pupil. In about four years later, in 2013, questionnaires and surveys were sent to the parents whose children participated in the original study. Those parents were contacted via email. Instruments Social Responsiveness Scale (SRS). The SRS is a questionnaire that assesses the severity of autism symptoms in children with ASD (Constantino & Gruber, 2005; Moul, Cauchi, Hawes, Brennan & Dadds, 2015). The SRS offers four forms each dedicated for a specific age group. For the current research the School-Age Form has been chosen. This form is for the age group of 4 through 18 years and can be filled in by a parent or a teacher of the Development of ODD and CD symptoms in ASD child, but in the current study only parents were involved. This test takes 15 to 20 minutes to complete. The SRS is a 65 item scale and contains five subscales, namely Social Awareness, Social Cognition, Social Communication, Social Motivation and Autistic Mannerisms (includes Restricted Interests and Repetitive Behaviour). Each item is rated on a 4-point scale: 0-Never true, 1-Sometimes true, 2-Often true, and 3-Almost always true. Of the 65 items, 17 items are reverse scored. Via this 4-point scale, the raw scores of the five subscales and total raw scores, which are the raw scores of the five subscales combined, are measured and filled in on a profile sheet. The total raw scores will be converted to total T-scores using standardization tables. The Total T-scores are divided into three groups: Severe range (Tscore >75), Mild to moderate range (T-score 60-75), and Normal range (T-score <60). The SRS has been compared with other more time-intensive tools like the autism diagnostic interview-revises (ADI-R) and according to that the SRS shows to have a good predictive validity for ASD (Constantino, Davis, Todd, Schindler, Gross, Brophy, Metzger, Shoushtari, Splinter & Reich, 2003). The SRS has a good reliability and sensitivity, but is poor on its specificity (Moul, Cauchi, Hawes, Brennan & Dadds, 2015). Vragenlijst voor Gedragsproblemen bij Kinderen (VvGK). The VvGK measures the extent to which the symptoms of the behavioural disorders ADHD, ODD and CD are present in children (Oosterlaan, Scheres, Antrop, Roeyers & Sergeant, 2000). It is a Dutch adjustment of the Disruptive Behaviour Disorders rating scale (Pelham, Gnagy, Greenslade & Milich, 1992). This test contains 42 items, behaviour descriptions that are based on the DSM-IV, and four subscales: inattentive, hyperactivity, ODD and CD. In the current study, only the data about ODD and CD have been included. This form is for the age group of 6 through 16 years and has to be filled in by a parent or a teacher of the child. An example of an item that has to be answered in this questionnaire would be: “Abuses people physically”. The items are rated on a 4-point scale: 1-Not at all, 2-A little, 3-Quite a lot, and 4-Very much. The raw scores are Development of ODD and CD symptoms in ASD measured by adding up the scores per scale. These total scores can be compared with norm groups. According to COTAN (2001), the reliability of this test is sufficient. The construct validity was rated good, but the criteria validity was rated inadequate/inapplicable, because, according of the authors of this test, the VvGK is not designed for a predictive purpose. The criterion validity does therefore not apply for this test. Data analysis In order to test the hypotheses that are shown in the introduction, paired sample t-tests will be done. These hypotheses are set up to (1) look if there is a decrease in ODD and CD symptoms in children diagnosed with ASD over time and (2) if there is a decrease in ASD symptoms over time. A paired sample t-test will be a good test to assess the first two hypotheses, because these paired sample t-test will take a look at the mean differences of the different variables over time. Scores of the VvGK for both ODD and CD and scores of the SRS for ASD will be tested separately. Results Three paired sample t-tests were conducted and the descriptive statistics of these tests are shown in table 2. The first paired sample t-test shows the mean scores on the VvGK for ODD and shows no significant decrease in the VvGK score for ODD over time (t (52) = 0.66; p = 0.51 (two-tailed)), with a mean difference of -0.32. This does not agree with what was expected, because a significant decrease of ODD over time was expected. The second paired sample t-test shows the mean scores on the VvGK for CD and shows a no significant decrease in the VvGK score for CD over time (t (53) = -1.03; p = 0.31 (two-tailed)), with a mean difference of 0.28. This also is not in line with what was expected in the first hypothesis, because a significant decrease in CD symptoms over time was Development of ODD and CD symptoms in ASD expected. So, the first hypothesis is not statistically confirmed, because the symptoms of ODD and CD in children and adolescents did not decrease over time. The third paired sample t-test tests the second hypothesis and is based on the scores of the SRS. A significant decrease for the SRS scores over time (t (53) = 2.64; p = 0.01 (twotailed)) was found, with a mean difference of 7.54. This significant result agrees with what was expected in the second hypothesis, because these results indicate that there is a significant decrease of ASD symptoms in children and adolescents with ASD over time. Since it was assumed that both ASD and ODD/CD would decrease over time, a correlation matrix (table 3) was, in addition to the paired sample t-tests, conducted from the data. The total scores of ODD, CD and SRS for both T1 and T2 were used. The largest significant correlations that were found are between SRS T1 and SRS T2 (r = 0.622; p < 0.001) and ODD T1 and ODD T2 (r = 0.643; p < 0.001). What seems odd is that the correlation between CD T1 and CD T2 is lower than might be expected (r = 0.367; p = 0.004). It is still a medium to large effect, but one might expect a similar result as was found with SRS and ODD. Another strong correlation was between ODD T2 and CD t2 (r = 0.775; p > 0.001) and also ODD T1 and CD T1 were positive correlated (r = 0.4; p < 0.001). Finally, it was found that during T1 SRS is not correlated with ODD and CD, but after 4 years SRS has a medium to large correlation with both ODD and CD. Table 2 Descriptive statics of paired sample t-tests Mean N ODD T1 6.09 53 ODD T2 5.77 53 CD T1 0.80 54 CD T2 1.07 54 SRS T1 82.38 54 SRS T2 74.83 54 SD 3.52 4.58 1.20 2.10 1.20 3.56 Development of ODD and CD symptoms in ASD Table 3 Correlations between the different variables ODD T1 ODD T2 CD T1 ODD T1 1 ** ODD T2 .643 1 ** * CD T1 .400 .324 1 ** ** ** CD T2 .502 .775 .387 SRS T1 .259 .122 -.174 ** SRS T2 .077 .372 -.139 **. Correlation is significant at the 0.01 level (2-tailed). *. Correlation is significant at the 0.05 level (2-tailed). CD T2 1 .025 .342* SRS T1 SRS T2 1 .622** 1 Discussion The purpose of the current study was to see whether the symptoms of ODD and CD in children and adolescents with ASD decrease over time, and whether their ASD symptoms decrease as well. Literature showed that the ASD symptoms of children and adolescents with ASD decrease over time (Pellicano, 2012). It was therefore assumed that in the current research the ASD symptoms would decrease as well. Furthermore, it was found that the symptoms of ODD and CD in children diagnosed with ODD and CD also decrease over time (Frick and Lonely, 1999). Thereby, research about the stability of ODD and CD diagnosis showed that after a couple of years there is a decrease of children who meet the criteria for both diagnosis (Lahey, Loeber, Hart, Frick, Applegate, Zhang, et.al., 1995; Nock, Kazdin, Hiripi & Kessler, 2007; Steiner & Remsing, 2007). Therefore, it was assumed that ODD and CD symptoms in children and adolescents diagnosed with ASD would also decrease over a period of time. One of the major findings of the current research is that the ASD symptoms of the children and adolescents in the current study’s sample indeed decreased over time. In that way, one hypothesis was confirmed. Another major finding was that the symptoms of ODD and CD of the children and adolescents that were assesses in the current study, remained stable over time. So, a decrease of ODD and CD symptoms in children and adolescents was Development of ODD and CD symptoms in ASD not confirmed. Finally, positive correlations were found between ODD and CD on both times of assessment, which seems to support the idea that both disorders have something in common and it might say something about the idea that ODD could be a precursor of CD. ASD scores on the SRS had a medium to large positive correlation with ODD and CD at the second moment of assessment. The strange thing is that the symptoms of ODD and CD in children and adolescents with ASD did not decrease over time, while literature showed that symptoms in children diagnosed with ODD and CD do decrease over time. Furthermore, it was established that over a period of time half of the children diagnosed earlier with CD did not meet the criteria of CD anymore and 70% of the children diagnosed with ODD did not meet their diagnosis anymore when they were reassessed at the age of 18 (Lahey, Loeber, Hart, Frick, Applegate, Zhang, et.al., 1995; Nock, Kazdin, Hiripi & Kessler, 2007). The main difference between the current study and these studies that established a decrease in ODD/CD symptoms and diagnosis over time, is that in the current study ASD is involved. It might be possible that the diagnosis of ASD has a stabilizing effect on the ODD/CD symptoms within these children and adolescents with ASD. As mentioned previously, ASD has sometimes been associated with offending, violent and criminal behaviour, which also occurs in ODD and CD (Mouridsen, 2012). However, these studies about the link between ASD and offending, violent and criminal behaviour had no strong evidence for this association. Other studies established the possibility of the link between offending and criminal behaviour, namely that these behaviours might be related to a lack of understanding social cues, that these behaviours could occur due to stress of changes in their routines or that these behaviours might be one of their obsessions (BaronCohen, 1988; Barry-Walsh & Mullen, 2004; Haskins & Silva, 2006). Finally, it was established that one could speak of a three-way model of ODD in ASD (Mandy, Roughna & Skuse, 2013). In other words, ODD symptoms are known to be present in individuals Development of ODD and CD symptoms in ASD diagnosed with ASD. So, maybe it is possible that that the certain characteristics of children and adolescents with ASD have a stabilizing effect on the ODD and CD symptoms and therefore the severity these ODD and CD symptoms in children and adolescents with ASD remains the same over 4 years in the current study. Another reason that might contribute to the fact that the ODD/CD remained stable in the current study, could be the age of the children of the parents that contributed. In the current study the average age was approximately 13 years during the first moment of assessment and 17 years during the second moment of assessment. During this period a child develops al lot, because the child reaches puberty and adolescence. Adolescence means becoming an adult and lasts from 10 to 21 years old (Westenberg, 2008). During adolescence a child also reaches puberty, which lasts from 10 to 15/16 years old. During the time of adolescence, a child is becoming more independent and is starting to detach from its parents. There is also a strong increase of emotional problems, like depression and anger. During puberty a child experiences a big sensitivity for stress (Arnett, 1999). Adolescents are therefore relatively easily irritated or angry. Due to these developments and changes within adolescents, problem behaviours are likely to occur (Farrington, 2004). For example, there is an increase of serious misbehaviour. The number of delinquencies and behaviour disorders increase strongly, but also misbehaviours like disobeying school rules are very common. Moffitt (1993) found that the number of arrests reaches its peak during the period of 15 to 20 years. Thereby, this study has found that the number of new offenders has a strong increase until the age of 16 years old. A study about the patterns and pathways of offending behaviour showed that the age group of 16 to 20 years old contained the highest number of offenders (Francis, Soothill & Fligelstone, 2004). So, according to these studies, adolescence is a period of development and change, associated with stress, emotional problems and therefore problem behaviour as a result. In the sample of the current study, these children with ASD should also Development of ODD and CD symptoms in ASD have experienced these developments, beside their ASD development. The problem behaviours that are associated with adolescence are similar to the symptoms of ODD/CD, like offending, aggressive, and criminal behaviour. The items of the VvGK that represent ODD and CD are similar to the characteristics of puberty, especially the items for ODD. For example, an item for ODD is “argues with adults”, which is very likely to occur in puberty. Other items of the VvGK for ODD that are pretty consistent with characteristics of puberty, asks if a child opposes to rules of adults, misbehaves, is often angry and is easily irritated. The items of the VvGK for CD are more severe, but include offending and criminal behaviour that, like mentioned previously, have also been associated with puberty and adolescence. Most of the children that were assessed in the current study at the first moment of assessment did not yet reach puberty or adolescence or were at the beginning of puberty or adolescence. What if their comorbid ODD/CD symptoms were naturally decreasing after the first moment of assessment, but during those four years between the two moments of assessment puberty began and, just like in normal children, problem behaviours increased and resulted in a stability of ODD/CD symptoms at the second moment of assessment. In other words, the characteristics of puberty were assessed and kept the ODD/CD symptoms at the same level. The studies that stated a decrease of ODD/CD symptoms and diagnosis, were assessed in children with ODD/CD that did not yet reach puberty or were just at the beginning of it or were assessed when puberty was over. Thus, it could be the case that the characteristics of puberty had an influence on the current study. On the basis of this alternative explanation, a limitation has to be mentioned. If this explanation is true and the characteristics of puberty really had an influence on the current research, this should have been taking into account. This implicates that maybe the moment of assessment was not right and better result would have been found if the time between these two moments was longer. The time between these two moments in the current study might be Development of ODD and CD symptoms in ASD relatively low, since better patterns of change can be seen in studies with a longer period of assessment (Nock, Hiripi & Kessler, 2007). Another implication might be that only parents were questioned. A parent might not have the ability to distinguish symptoms of ODD/CD and puberty characteristics within their child diagnosed with ASD. It might be possible that, mainly during the second moment of assessment, puberty was assessed in their children with ASD instead of the ODD/CD symptoms. Overall, it might be more desirable that information was retrieved directly from the child, instead of indirectly from one of their parents and maybe then other results would have come out. The other alternative explanation, previously mentioned, said that maybe the ASD symptoms within children and adolescents with ASD might have a stabilizing effect on the level of ODD/CD symptoms within children and adolescents diagnosed with ASD. This could suggest that only individuals with ASD and not without ASD were assessed, which might be a limitation. In addition, the sample of the current research was not very big and also considered to be a limitation. These limitations could give a good perspective for eventual further research. First of all, the biggest drops of ODD/CD symptoms and diagnosis of children diagnosed with these disorders that were found in previous research, assessed these children over a big period of time and they were mostly assessed when puberty did not enter yet or had just began or after puberty. For this reason, it might be wise to have the second moment of assessment, which in the current study had a mean age around the 17, a few years after puberty has ended or add an extra moment of assessment. In that way, a study is created with a pre-puberty, puberty and post-puberty moment assessment in children diagnosed with ASD, and maybe the influence of puberty could be detected. In addition, a control group could be added with children that are not diagnosed with ASD to detect the differences of the levels of ODD/CD symptoms Development of ODD and CD symptoms in ASD between children with ASD and without ASD. It might be possible that ODD symptoms could be found during puberty in children without ASD, but not before and after puberty. These ideas for further research could provide more information about the association of comorbid ODD and CD symptoms in children with ASD. Furthermore, in the current study correlations have been found between the scores of ASD, ODD and CD at the second moment of assessment. This might suggest that ASD and ODD/CD might be more related than could be established in the current study. When more participants in further research about this subject are added and more research about the cohesion between ASD and ODD/CD will be done, interesting results might be found. In the current study a decrease of ASD symptoms within children and adolescents with ASD has been established. Results showed no changes of their comorbid ODD and CD symptoms, and therefore little associations between ASD and ODD/CD within children with ASD have been found. Further research about these associations is urgent, because comorbidity of ODD in children with ASD is common and a small group of children, when untreated, with ODD will develop CD, which is a more severe problem (Connor, 2002). If we know more about how ASD and ODD/CD are related within these children with ASD, early interventions could be developed and the behaviour problems that occur in these children could be decreased or stopped. References American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders (4th ed.). Washington, DC: Author. American Psychiatric Association. (2013). Diagnostic and statistical manual of mental Development of ODD and CD symptoms in ASD disorders (5th ed.). Washington, DC: Author. Amr, M., Raddad, D., El-Mehesh, F., Bakr., A., Sallam, K., & Amin, T. (2012). Comorbid psychiatric disorders in Arab children with Autism spectrum disorders. Research in Autism Spectrum Disorders, 6(1), 240-248. Arnett, J. J. (1999). Adolescent storm and stress, reconsidered. American Psychologist, 54, 317-326. Baron-Cohen, S. (1988). An assessment of violence in a young man with Asperger’s syndrome. Journal of Child Psychology and Psychiatry, 29, 351–360. Barry-Walsh, J. B., & Mullen, P. E. (2004). Forensic aspects of Asperger’s syndrome. Journal of Forensic Psychiatry & Psychology, 15, 96–107. Cheely, C. A., Carpenter, L. A., Letourneau, E. J., Nicholas, J. S., Charles, J., & King, L. B. (2012). The prevalence of youth with autism spectrum disorders in the criminal justice system. Journal of Autism and Development Disorders, 42(9), 1856-1886. Constantino, J. N., Davis, S. A., Todd, R. D., Schindler, M. K, Gross, M. M., Brophy, S. L., Metzger, L. M., Shoushtari, C. S., Splinter, R., & Reich, W. (2003). Validation of a Brief Quantitative Measure of Autistic Traits: Comparison of the Social Responsiveness Scale with the Autism Diagnostic Interview-Revised. Journal of Autism and Developmental Disorders, 33(4), 427-433. Constantino, J. N., & Gruber, C. P. (2005). Social Responsiveness Scale (SRS). Los Angeles, CA: Western Psychological Services. Comer, R.J. (2004). Abnormal psychology. New york: Worth. Development of ODD and CD symptoms in ASD Connor, D.F. (2002), Aggression and Antisocial Behavior in Children and Adolescents: Research and Treatment. New York: The Guilford Press. Costello, E. J., Mustillo, S., Erkanli, A., Keeler, G., & Angold, A. (2003). Prevalence and development of psychiatric disorders in childhood and adolescence. American Medical Association, 60(8), 837-844. Del Valle, P., Kelley, S. L., & Seoanes, J. E. (2001). The "Oppositional Defiant" and "Conduct Disorder" Child: A Brief Review of Etiology, Assessment, and Treatment. Behavioral Development Bulletin, 10(1), 36-41. Egberink, I.J.L., Janssen, N.A.M., & Vermeulen, C.S.M. (21-03-2016). COTAN 2001, Vragenlijst voor Gedragsproblemen bij Kinderen (VvGK). Bekeken via www.cotandocumentatie.nl. Farrington, D. P. (2004). Conduct disorder, aggression, and delinquency. In R. M. Lerner & L. Steinberg (2004), Handbook of Adolescent Psychology, 2nd edition (pp. 627-664). Hoboken, NJ: John Wiley. Fombonne, E. (2009). Epidemiology of pervasive developmental disorders. Pediatric Research, 65(6), 591–598. Francis, B., Soothill, K., & Fligelstone, R. (2004). Identifying Patterns and Pathways of Offending Behaviour: A New Approach to Typologies of Crime. European Journal of Criminology, 1(1), 48-87. Frick, P.J., & Loney, B.R. (1999). Outcomes of children and adolescents with oppositional defiant disorder and conduct disorder. In H.C. Quay, & A.E. Hogan (Eds.), Handbook of disruptive behavior disorders (pp. 507-524). Gadow, K. D., DeVincent, C. J., Pomeroy, J., & Azizian, A. (2004). Psychiatric Development of ODD and CD symptoms in ASD symptoms in preschool children with PDD and clinic and comparison samples. Journal of Autism and Developmental Disorders, 34, 379–393. Gadow, K. D., DeVincent, C. J., Pomeroy, J., & Azizian, A. (2005). Comparison of DSM-IV symptoms in elementary school-age children with PDD versus clinic and community samples. Autism, 9, 392–415. Gjevik, E., Eldevik, S., Fjæran-Granum, T., & Sponheim, E. (2011). Kiddie-SADS reveals high rates of DSM-IV disorders in children and adolescents with autism spectrum disorders. Journal of Autism and Developmental Disorders, 41, 761-769 Haskins, B. G., & Silva, J. A. (2006). Asperger's disorder and criminal behavior: forensicpsychiatric considerations. Journal of the American Academy of Psychiatry and the Law Online, 34(3), 374-384. Kaat, A. J., & Lecavalier, L. (2013). Disruptive behavior disorders in children and adolescents with autism spectrum disorders: A review of the prevalence, presentation, and treatment. Research in Autism Spectrum Disorders, 7(12), 1579-1594. Kann, R. T., & Hanna, F. J. (2000). Disruptive Disorders in Children and Adolescents: How Do Girls Differ from Boys? Journal of Counseling & Development, 78, 267-274. Lahey, B.J., Loeber, R., Hart, E., Frick, P., Applegate, B., Zhang, Q., e.a. (1995). Four-year longitudinal study of conduct disorder in boys: Patterns and predictors of persistence. Journal of Abnormal Psychology, 104, 83-93. Lahey, B. B., Van Hulle, C. A., Rathouz, P. J., Rodgers, J. L., D’Onofrio, B. M., & Waldman, I. D. (2009). Are Oppositional-Defiant and Hyperactive–Inattentive Symptoms Developmental Precursors to Conduct Problems in Late Childhood?: Genetic and Environmental Links. Journal of Abnormal Child Psychology, 37, 45-58. Development of ODD and CD symptoms in ASD Levy, S. E., Mandell, D. S., & Schultz, R. T. (2009). Autism. The Lancet, 374(9701), 16271638. Leyfer, O. T., Folstein, S. E., Bacalman, S., Davis, N. O., Dinh, E., Morgan, J., TagerFlusberg, H., & Lainhart, J. E. (2006). Comorbid psychiatric disorders in children with autism: Interview development and rates of disorders. Journal of Autism and Developmental Disorders, 36, 849-861. Lindhiem, O., Bennett, C. B., Hipwell, A. E., & Pardini, D. A. (2015). Beyond Symptom Counts for Diagnosing Oppositional Defiant Disorder and Conduct Disorder. Journal of Abnormal Child Psychology, 43(7), 1379-1397. Loeber, R., Burke, J., & Pardini, D.A. (2009). Perspectives on oppositional defiant disorder, conduct disorder, and psychopathic features. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 50, 133-142. Mandy, W., Roughan, L., & Skuse, D. (2013). Three Dimensions of Oppositionality in Autism Spectrum Disorder. Journal of Abnormal Child Psychology, 42, 291-300. Mattila, M.-L., Hurtig, T., Haapsamo, H., Jussila, K., Kuusikko-Gauffin, S., Kielinen, M., et al. (2010). Comorbid psychiatric disorders associated with Asperger syndrome/highfunctioning autism: A community- and clinic-based study. Journal of Autism and Developmental Disorders, 40, 1080–1093. Maughan, B., Rowe, R., Messer, J., Goodman, R., & Meltzer, H. (2004). Conduct Disorder and Oppositional Defiant Disorder in a national sample: developmental epidemiology. Journal of Child Psychology and Psychiatry, 45(3), 609-621. Moffitt, T. E. (1993). Adolescence-Limited and Life-Course-Persistent Antisocial Behavior: A Developmental Taxonomy. Psychological Review, 100(4), 674-701. Development of ODD and CD symptoms in ASD Moul, C., Cauchi, A., Hawes, D. J., Brennan, J., & Dadds, M. R. (2015). Differentiating Autism Spectrum Disorder and Overlapping Psychopathology with a Brief Version of the Social Responsiveness Scale. Child Psychiatry, 46, 108-117. Mouridsen, S. E. (2012). Current status of research on autism spectrum disorders and offending. Research in Autism Spectrum Disorders, 6(1), 79-86. Nock, M.K., Kazdin, A.E., Hiripi, E., & Kessler, R.C. (2007). Lifetime prevalence, correlates, and persistence of oppositional defiant disorder: results from the National Comorbidity Survey Replication. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 48, 703-713. Oosterlaan, J., Scheres, A., Antrop, I., Roeyers, H. & Sergeant, J.A. (2000). Handleiding bij de Vragenlijst voor Gedragsproblemen bij Kinderen, VvGK. Lisse: Harcourt Test Publishers. Pelham, W. E., Gnagy, E, M,, Greenslade, K. E., & Milich R. (1992). Teacher ratings of DSM-III-R symptoms for the disruptive behaviors disorder. Journal of the American Academy of Child and Adolescent Psychiatry, 31(2), 210-218. Pellicano, E. (2012). Do Autistic symptoms persist across time? Evidence of substantial change in symptomatology over a 3-year period in cognitively able children with autism. American Journal of Intellectual and Developmental Disabilities, 117(2), 156166. Scheeren, A. M., de Rosnay, M., Koot, H. M., & Begeer, S. (2013). Rethinking theory of mind in high-functioning autism spectrum disorder. Journal of Child Psychology and Psychiatry, 54(6), 628–635. Scheeren, A. M., Koot, H. M., & Begeer, S. (2012). Social interaction style of children Development of ODD and CD symptoms in ASD and adolescents with high-functioning autism spectrum disorder. Journal of Autism and Developmental Disorders, 42(10), 2046–2055. Simonoff, E., Pickles, A., Charman, T., Chandler, S., Loucas, T., & Baird, G. (2008). Psychiatric disorders in children with autism spectrum disorders: Prevalence, comorbidity, and associated factors in a population-derived sample. Journal of the American Academy of Child & Adolescent Psychiatry, 47(8), 921-929. Steiner, H., Remsing, L.; Work Group on Quality Issues. (2007). Practice parameter for the assessment and treatment of children and adolescents with oppositional defiant disorder. Journal of the American Academy of Child and Adolescent Psychiatry, 46, 126-141. Williams, L. W., Matson, J. L., Goldin, R. L., & Adams, H. L. (2014). Children assessed for Autism Spectrum Disorder: Developmental delay and change over time in BDI-2 developmental quotients. Research in Autism Spectrum Disorders, 8(11), 1500-1507. Worley, J. A., & Matson, J. L. (2012). Comparing symptoms of autism spectrum disorders using the current DSM-IV-TR diagnostic criteria and the proposed DSM-V diagnostic criteria. Research in Autism Spectrum Disorders, 6(2), 965-970.