View in EDS HTML Full Text PDF Full Text

A General Practice-Based Study of the Relationship between Indicators of Mental Illness and Challenging Behaviour among Adults with Intellectual Disabilities

Saved in:
Bibliographic Details
Title: A General Practice-Based Study of the Relationship between Indicators of Mental Illness and Challenging Behaviour among Adults with Intellectual Disabilities
Language: English
Authors: Felce, D., Kerr, M., Hastings, R. P.
Source: Journal of Intellectual Disability Research. Mar 2009 53(3):243-254.
Availability: Blackwell Publishing. 350 Main Street, Malden, MA 02148. Tel: 800-835-6770; Tel: 781-388-8599; Fax: 781-388-8232; e-mail: customerservices@blackwellpublishing.com; Web site: http://www.blackwellpublishing.com/jnl_default.asp
Peer Reviewed: Y
Physical Description: PDF
Page Count: 12
Publication Date: 2009
Document Type: Journal Articles
Reports - Research
Descriptors: Mental Retardation, Mental Disorders, Adults, Antisocial Behavior, Correlation, Pervasive Developmental Disorders, Adjustment (to Environment), Multiple Regression Analysis
DOI: 10.1111/j.1365-2788.2008.01131.x
ISSN: 0964-2633
Abstract: Background: Existing studies tend to show a positive association between mental illness and challenging behaviour among adults with intellectual disabilities (ID). However, whether the association is direct or artefactual is less clear. The purpose was to explore the association between psychiatric status and level of challenging behaviour, while controlling for adaptive behaviour and occurrence of autistic spectrum disorders. Methods: Data were collected on the age, gender, adaptive and challenging behaviour, social impairment and psychiatric status of 312 adults with ID. Participants were divided according to psychiatric status, group equivalence in adaptive behaviour and the presence of autistic spectrum disorders achieved, and differences in challenging behaviour explored. In addition, multiple regression was used to examine the association between psychiatric status and challenging behaviour after controlling for other participant characteristics and to test whether the interaction between psychiatric status and adaptive behaviour added significantly to explanation. Results: Challenging behaviour was higher among participants meeting threshold levels on the psychiatric screen. The regression analysis confirmed the association and demonstrated an interaction between total score on the psychiatric screen and level of adaptive behaviour. This moderated effect showed the relationship between psychiatric status and challenging behaviour to be stronger at lower adaptive behaviour. Conclusions: This study reinforces previous findings that psychiatric morbidity among people with ID is associated with higher levels of challenging behaviour and supports predictions that this association is more pronounced for people with severe ID. The precise nature and causal direction of the association requires further clarification. However, the understanding of how psychiatric problems might contribute to challenging behaviour needs to be part of the clinical appreciation of such behaviour.
Abstractor: As Provided
Number of References: 34
Entry Date: 2009
Accession Number: EJ828609
Database: ERIC
Full text is not displayed to guests.
FullText Links:
  – Type: pdflink
    Url: https://content.ebscohost.com/cds/retrieve?content=AQICAHj0k_4E0hTGH8RJwT4gCJyBsGNe_WN95AvKlDbXJGqwxwE9LFCfsEbZfCWezsalIxutAAAA4TCB3gYJKoZIhvcNAQcGoIHQMIHNAgEAMIHHBgkqhkiG9w0BBwEwHgYJYIZIAWUDBAEuMBEEDAUBWIJzr5UXSUJAMwIBEICBmdKqcs_OxAG2Bq6i7RFLs7UMLh7GEVX2ZxCVbg7xG5CDmENo0Z6bHfyKSiqaryEle2eav3zFjC6t71LjU47tMJ8V5dUXApNk762nZB6U_jZNrenhPbu0o3xID7INasQB6-uMnVDMYyv6RVnt696uzLjoxRhZlcxAaMa6EwEbgnPUd2RE5zKsF0W1iYMaXiC-9Be7m_45ss2WzQ==
Text:
  Availability: 1
  Value: <anid>AN0036518945;eul01mar.09;2019Jun04.10:46;v2.2.500</anid> <title id="AN0036518945-1">A general practice-based study of the relationship between indicators of mental illness and challenging behaviour among adults with intellectual disabilities. </title> <p>Background  Existing studies tend to show a positive association between mental illness and challenging behaviour among adults with intellectual disabilities (ID). However, whether the association is direct or artefactual is less clear. The purpose was to explore the association between psychiatric status and level of challenging behaviour, while controlling for adaptive behaviour and occurrence of autistic spectrum disorders. Methods  Data were collected on the age, gender, adaptive and challenging behaviour, social impairment and psychiatric status of 312 adults with ID. Participants were divided according to psychiatric status, group equivalence in adaptive behaviour and the presence of autistic spectrum disorders achieved, and differences in challenging behaviour explored. In addition, multiple regression was used to examine the association between psychiatric status and challenging behaviour after controlling for other participant characteristics and to test whether the interaction between psychiatric status and adaptive behaviour added significantly to explanation. Results  Challenging behaviour was higher among participants meeting threshold levels on the psychiatric screen. The regression analysis confirmed the association and demonstrated an interaction between total score on the psychiatric screen and level of adaptive behaviour. This moderated effect showed the relationship between psychiatric status and challenging behaviour to be stronger at lower adaptive behaviour. Conclusions  This study reinforces previous findings that psychiatric morbidity among people with ID is associated with higher levels of challenging behaviour and supports predictions that this association is more pronounced for people with severe ID. The precise nature and causal direction of the association requires further clarification. However, the understanding of how psychiatric problems might contribute to challenging behaviour needs to be part of the clinical appreciation of such behaviour.</p> <p>Keywords: intellectual disabilities; psychiatric status; challenging behaviour</p> <p>The prevalence of mental illness among people with intellectual disabilities (ID) remains contentious, so much so that [<reflink idref="bib11" id="ref1">11</reflink>]) began a recent paper on the topic by stating that the 'prevalence of mental ill‐health among adults with intellectual disabilities is unknown' (p. 27). Existing studies have shown a wide range in reported prevalence rates, which may be attributable to variation in the selective nature of study populations, diagnostic criteria, ascertainment methods, cohort sizes and whether point or lifetime rates were being reported. In their own study, [<reflink idref="bib11" id="ref2">11</reflink>]) ascertained the prevalence of mental ill‐health among a large sample of adults with ID (16 years and over), which constituted 3.33 per 1000 of the adult general population. They found point prevalence rates of 40.9% based on clinical diagnosis, 35.2% based on DC‐LD criteria ([<reflink idref="bib29" id="ref3">29</reflink>]), 16.6% based on International Classification of Diseases (ICD)‐10‐DCR criteria ([<reflink idref="bib34" id="ref4">34</reflink>]) and 15.7% based on Diagnostic and Statistical Manual of Mental Disorders (DSM)‐IV‐TR criteria ([<reflink idref="bib3" id="ref5">3</reflink>]). Findings across diagnostic criteria were sensitive to whether problem behaviours and autistic spectrum disorder were included as indicative in themselves of mental ill‐health. Prevalence rates excluding problem behaviours and autistic spectrum disorder varied less, respectively 22.4%, 19.1%, 14.5% and 13.9%. However, this does not mean that these figures are necessarily more valid estimates as it has been argued that ICD and DSM diagnostic criteria do not take adequate account of the consequence of developmental level on how psychopathology within psychiatric disorders might present in this population ([<reflink idref="bib30" id="ref6">30</reflink>]; [<reflink idref="bib13" id="ref7">13</reflink>]; [<reflink idref="bib11" id="ref8">11</reflink>]).</p> <p>Prior to Cooper <emph>et al.</emph>'s study, [<reflink idref="bib32" id="ref9">32</reflink>]) reviewed the literature on the prevalence of psychiatric disorders among children and adults with ID to examine the evidence base for the proposition that mental ill‐health is increased among people with ID when compared with the general population. They concluded that, despite methodological variations and interpretation problems between studies, there was sufficient evidence to support a conclusion that psychiatric disorder is increased among children, a finding that could be attributed to a greater presence of pervasive developmental disorders and problem behaviours and possibly an increased rate of anxiety disorders. Whitaker and Read also concluded that evidence points to there being a higher prevalence rate of psychiatric disorder in adults with severe ID compared with adults with mild ID or adults without ID, a conclusion supported by recent data ([<reflink idref="bib12" id="ref10">12</reflink>]). However, evidence was insufficient for Whitaker and Read to conclude that the overall prevalence rate of psychiatric disorder for adults with mild ID was higher than it was among the general population.</p> <p>[<reflink idref="bib32" id="ref11">32</reflink>]) also noted that behaviour problems were more common among children and adults with ID than they were among children and adults without ID. There is evidence that the presence of problem behaviours is associated with both degree of disability ([<reflink idref="bib14" id="ref12">14</reflink>]) and the presence of autistic spectrum or pervasive developmental disorders ([<reflink idref="bib17" id="ref13">17</reflink>]; [<reflink idref="bib5" id="ref14">5</reflink>]). If the conclusion that psychiatric morbidity is also increased among people with more severe ID is correct, the associations between degree of disability, the presence of autistic spectrum or pervasive developmental disorders, the presence of behaviour problems and the presence of mental ill‐health run in the same direction. This creates a degree of complexity. As behaviour problems may themselves be utilised as indicators of mental ill‐health, care needs to be taken that the association between mental ill‐health and challenging behaviour is not tautological, with the presence of challenging behaviour influencing psychiatric diagnosis as well as contributing to a score on whatever measure is used to quantify challenging behaviour. In addition, care needs to be taken that the association is not spurious, because of the possible association of both quantities with either degree of disability or the presence of autistic spectrum or pervasive developmental disorders.</p> <p>[<reflink idref="bib14" id="ref15">14</reflink>]) suggests three ways in which the association between challenging behaviour and mental illness may arise in people with ID. First, challenging behaviours may represent the atypical presentation of the core symptoms of a psychiatric disorder in people with severe ID. If this was true, one would expect severity of disability to moderate the relationship between presence of mental illness and level of challenging behaviour, with the association being more potent among people with more severe disability. Second, challenging behaviours may occur as secondary features of psychiatric disorders among people with severe ID. Again, one might expect a moderating effect of severity of disability. Third, psychiatric disorders may act as establishing operations for operant‐maintained challenging behaviours. Here, no specific link to severity of disability is made. However, one might still exist if functional limitations, such as in symbolic communication, influenced the operant development and maintenance of challenging as opposed to other forms of behaviour.</p> <p>Existing studies tend to show a positive association between psychiatric illness and challenging behaviour among adults with ID (e.g. [<reflink idref="bib7" id="ref16">7</reflink>]; [<reflink idref="bib24" id="ref17">24</reflink>]; [<reflink idref="bib18" id="ref18">18</reflink>]; [<reflink idref="bib28" id="ref19">28</reflink>]). However, whether the association is direct or artefactual has not been definitively established. Moreover, whether severity of disability moderates the association between psychiatric status and extent of challenging behaviour has been studied in only a limited way. [<reflink idref="bib22" id="ref20">22</reflink>]) compared adults with mild, moderate, or severe/profound ID with or without depression. Depressed adults with severe/profound ID were more likely to show self‐injury, screaming and aggressive behaviour, whereas these behaviours were not associated with depression in the mild ID group. The authors suggested that these data support a hypothesis that challenging behaviours might be seen as depressive equivalents in those with severe ID. [<reflink idref="bib31" id="ref21">31</reflink>]) replicated the analysis of Marston <emph>et al.</emph>, but found no association between depression and challenging behaviours in people with severe ID. The measures used in both of these studies did not have established psychometric properties, analysis was limited to associations with depression, and statistical analyses were not conducted that directly compared the strength of association between depression and challenging behaviours for different levels of ID.</p> <p>The main purpose of the current study was, therefore, to explore the association between psychiatric status, as determined by a psychiatric screening inventory, and scores on a measure of challenging behaviour, while controlling for degree of disability, as reflected by level of adaptive behaviour, and occurrence of autistic spectrum disorders. By using a psychiatric screen based on DSM criteria, tautology between indicators of mental illness and the presence of problem behaviour or autistic spectrum disorder was minimised. Control for adaptive behaviour and the occurrence of autistic spectrum disorders was undertaken within the analysis so as to ensure any association between psychiatric status and challenging behaviour was independent of mutual association with these quantities. In the event of there being a significant association between psychiatric status and levels of challenging behaviour, the second purpose was to explore whether level of adaptive behaviour had a moderating effect on that association. We adopted a regression analysis approach so that main effects and interactions could be explored independent of one another within a large sample. The study drew on data collected for research designed to evaluate the impact of health checking for people with ID conducted within primary care on the identification of previously unidentified morbidity ([<reflink idref="bib4" id="ref22">4</reflink>]). Although the sample was not drawn at random, the fact that it was identified through primary care rather than via the rolls of learning disability services may make it generally more representative and less prone to bias towards co‐occurring pathology.</p> <hd id="AN0036518945-2">Method</hd> <p></p> <hd id="AN0036518945-3">Participants</hd> <p>Forty general practices within three health authorities in South and Mid Wales participated. They had a combined registered patient population of 354 000, 20% of the 1.8 m in the territory. Each practice identified their patients with an ID with help from the research team by using keyword searches of computerised notes and records of medication (e.g. for neuroleptic and anti‐epileptic drugs commonly prescribed to this population). Having recruited them into the study by using a pro forma letter, the practices collectively referred 374 adult patients with ID to the researchers for possible inclusion. Written consent or assent from carers was obtained for 318 participants, the latter when the patient lacked the capacity to consent. Complete datasets for the current study were available for 312 participants. Their characteristics are set out in Table 1. Participants were not randomly selected from a sampling frame with known properties. As a result, there are areas where the achieved sample was not representative of the population of people with ID as a whole. For example, one would have expected more men than women. However, in other aspects, including age, proportion living in the family home, ability and presence of challenging behaviour, sample characteristics were in line with other UK surveys.</p> <p>1 Characteristics of full sample (n = 312) and those meeting (n = 143) and not meeting (n = 169) psychiatric caseness*</p> <p> <ephtml> <table><thead valign="bottom"><tr><th><bold>Group</bold></th><th><bold>Mean age (SD)</bold></th><th><bold>Male (%)</bold></th><th><bold>Residence (%)</bold></th><th><bold>Mean ABS score (SD)</bold></th><th><bold>Challenging behaviour (%)</bold><bold>†</bold></th><th><bold>Triad of social impairments</bold><bold>‡</bold><bold> (%)</bold></th></tr><tr><th><bold>Independent</bold></th><th><bold>Family home</bold></th><th><bold>Staffed home</bold></th></tr></thead><tbody valign="top"><tr><td>Full sample (<italic>n</italic> = 312)</td><td>41.5 (14.8)</td><td>43</td><td>10</td><td>46</td><td>45</td><td>171.7 (70.5)</td><td>15</td><td>33</td></tr><tr><td>Above threshold for mental illness* (<italic>n</italic> = 143)</td><td>41.1 (13.8)</td><td>43</td><td>14</td><td>41</td><td>45</td><td>169.5 (69.5)</td><td>25</td><td>42</td></tr><tr><td>Below threshold for mental illness* (<italic>n</italic> = 169)</td><td>41.9 (15.7)</td><td>44</td><td>7</td><td>49</td><td>44</td><td>173.5 (71.4)</td><td>6</td><td>25</td></tr></tbody></table> </ephtml> </p> <p>1 *  Meeting threshold levels on the Psychopathology Instrument for Mentally Retarded Adults ([<reflink idref="bib23" id="ref23">23</reflink>]).</p> <ulist> <item>2 †   Either 5 items scored at level 3 on the Irritability and Hyperactivity domains of the Aberrant Behavior Checklist ([<reflink idref="bib2" id="ref24">2</reflink>]) or a combined score on these domains above 30.</item> <item>3 ‡   The triad of social impairments are characteristic of autistic spectrum disorder ([<reflink idref="bib33" id="ref25">33</reflink>]).</item> <item>4 ABS, Adaptive Behavior Scale ([<reflink idref="bib26" id="ref26">26</reflink>]).</item> </ulist> <hd id="AN0036518945-4">Procedures and measurement</hd> <p>The research received ethical approval. In addition to age, gender and place of residence, information was gained on each participant's adaptive behaviour, challenging behaviour, social impairment and psychiatric status by interviewing a carer who knew the person well.</p> <p>Adaptive behaviour was assessed by using Part One of the Adaptive Behavior Scale (2nd edition) (ABS) ([<reflink idref="bib26" id="ref27">26</reflink>]), which comprises 66 items spanning 10 domains of functioning. The authors report internal consistency coefficients averaged across age groups for the 10 domains ranging from 0.81 to 0.99 and correlation coefficients for test–retest reliability from 0.88 to 0.99 ([<reflink idref="bib26" id="ref28">26</reflink>]). Adequate levels of item discrimination, criterion‐related validity and construct validity are also reported ([<reflink idref="bib26" id="ref29">26</reflink>]). In this study, a total ABS raw score was calculated by combining the domain scores.</p> <p>Challenging behaviour was assessed by using the Aberrant Behavior Checklist (ABC) ([<reflink idref="bib2" id="ref30">2</reflink>]). The ABC comprises 58 behaviours, each relating to one of five sub‐scales: irritability, hyperactivity, inappropriate speech, stereotypy and lethargy. The authors report internal consistency coefficients for the five sub‐scales ranging from 0.86 to 0.94, correlation coefficients for test–retest reliability from 0.96 to 0.99, and correlation coefficients for inter‐rater reliability from 0.55 to 0.69. Scores on the irritability and hyperactivity domains were used to establish a criterion for categorising participants as having severe challenging behaviour, as we have done in previous research (e.g. [<reflink idref="bib20" id="ref31">20</reflink>]; [<reflink idref="bib27" id="ref32">27</reflink>]).</p> <p>Participant social impairment was assessed by using the Disability Assessment Schedule (DAS) ([<reflink idref="bib19" id="ref33">19</reflink>]). The DAS was designed to elicit information on abilities and behaviour problems in adults and children with ID. The schedule consists of eight sections of which four are concerned with physical and developmental skills, and four with behavioural abnormalities. Nine items relating to three of the latter four sections were used in the current study to assess the triad of social impairments, said to be characteristic of autism ([<reflink idref="bib33" id="ref34">33</reflink>]). These items focus on abnormalities of social and imaginative activities, stereotypies and echolalia. Test–retest reliability for the three sections concerned was reported by the authors to average 84%, with inter‐respondent reliability averaging 79%. Reaching a threshold level on each item results in an individual being categorised as having the triad of social impairments.</p> <p>Participant psychiatric status was assessed by using the Psychopathology Instrument for Mentally Retarded Adults (PIMRA) ([<reflink idref="bib23" id="ref35">23</reflink>]). The PIMRA comprises 56 psychopathological items divided equally into eight diagnostic domains reflecting major DSM III categories: schizophrenia, affective disorder, psychosexual disorder, adjustment disorder, anxiety disorder, somatoform disorder, personality disorder and inappropriate adjustment. The author reports an internal consistency coefficient for the total score of 0.83 and test–retest reliabilities for ratings by people other than the subject of 0.48–1.00 for the sub‐scale and total scores. The author suggests that the presence of four of the seven assessed items in each sub‐scale indicates a threshold level for that psychiatric problem. Using the PIMRA scores, three indicators of psychiatric status were employed. A participant was categorised as meeting psychiatric caseness if at least one sub‐scale reached the threshold level. The number of threshold levels each participant attained was calculated (possible range = 0–8). In addition, a total PIMRA score across the 56 items was calculated.</p> <hd id="AN0036518945-5">Design and data analysis</hd> <p>Two approaches were taken to exploring the association between presence of mental illness and challenging behaviour while controlling for level of adaptive behaviour and occurrence of autistic spectrum disorders. In the first, a combination of partitioning the data and creating matched subgroups where necessary was used to remove the influence of confounding factors. In the second, multivariate regression was used to explore the association between the level of challenging behaviour and various indicators of psychiatric status after having first taken account of other personal characteristics.</p> <hd id="AN0036518945-6">Method 1</hd> <p>In the first approach, the 312 participants were divided into two groups based on assessed psychiatric caseness (see Table 1); 143 (46%) were categorised as meeting the threshold for mental illness and 169 (54%) were categorised as below the threshold for mental illness. The two groups were similar to each other in age, gender distribution and adaptive behaviour. The slight differences that existed between them were far from being statistically significant (Mann–Whitney <emph>U</emph> = 11927, <emph>P</emph> = 0.84; <emph>χ</emph><sups>2</sups> = 0.04, d.f. = 1, <emph>P</emph> = 0.84; Mann–Whitney <emph>U</emph> = 11623.5, <emph>P</emph> = 0.56 respectively). As a result of this equivalence, any difference in challenging behaviour would likely be independent of the impact of age, gender and adaptive behaviour without any further need for analytic control.</p> <p>However, the proportion categorised as having the triad of social impairments characteristic of autistic spectrum disorders was significantly higher in the mental illness group (<emph>χ</emph><sups>2</sups> = 10.30, d.f. = 1, <emph>P</emph> < 0.005). Therefore, any difference in challenging behaviour between the groups would not be independent of the impact of autistic spectrum disorder. This gives rise to the need to control additionally for the presence of these disorders, while also retaining equivalence of adaptive behaviour. The first investigation made was to partition the data into those with and without the triad of social impairments and explore the similarity in adaptive behaviour between those with and without psychiatric caseness separately. There were 102 participants with the triad of social impairments. Those who met threshold level for mental illness (<emph>n</emph> = 60) were equivalent in adaptive behaviour to those below the threshold level (<emph>n</emph> = 42) (ABS means = 119.4 and 116.1 respectively, SDs = 51.2 and 51.7, Mann–Whitney <emph>U</emph> = 1233.0, <emph>P</emph> = 0.85). There were 210 participants who were assessed as not having the triad of social impairments. Those who met threshold level for mental illness (<emph>n</emph> = 83) had non‐significantly higher adaptive behaviour to those below the threshold level (<emph>n</emph> = 127) (ABS means = 205.7 and 192.5 respectively, SDs = 57.6 and 66.9, Mann–Whitney <emph>U</emph> = 4739.0, <emph>P</emph> = 0.22). The effect size of this difference is of a level considered worthy of note by using common guidelines (i.e. in the 0.20–0.30 range). Therefore, it was important to take a subsample to reduce the extent of difference. The target was to achieve a mean ABS close to the 205.7 figure found among those who met threshold level for mental illness. Twenty‐five people with lower adaptive behaviour were therefore removed from the group below threshold level until close similarity was reached (mean ABS score of the adjusted sample (<emph>n</emph> = 102) = 204.7, SD = 65.6, Mann–Whitney <emph>U</emph> = 4122, <emph>P</emph> = 0.76). Selection of those to remove was done in the following way. The database was ordered by ascending ABS score. For ABS scores below the target mean, when there was more than one member in the below threshold level group with a score similar to a mental illness group member, one of them was eliminated (the person adjacent to the mental illness group member was retained). This procedure meant that eliminated people were not simply those with the lowest ABS scores; they were selected from across the spectrum of those who had ABS scores below the mean so as to maintain the range and variance in the sample. They were also selected without regard to any assessment of challenging behaviour.</p> <p>Non‐parametric statistical methods were employed. Differences between groups were tested for significance by using a <emph>χ</emph><sups>2</sups> test in relation to the proportion considered to have severe challenging behaviour and the Mann–Whitney <emph>U</emph> test in relation to total ABC scores. The relative risk of being considered to have severe challenging behaviour given psychiatric status was calculated, together with the associated 95% confidence interval. An effect size was calculated from the Mann–Whitney test statistics (<emph>m</emph>, <emph>n</emph>, <emph>U</emph>), using the formula <emph>U</emph>/<emph>mn</emph>, together with the associated 95% confidence interval ([<reflink idref="bib25" id="ref36">25</reflink>]). <emph>U</emph>/<emph>mn</emph> is equal to 0.5 when there is no effect and either 0 or 1 when there is a perfect effect or complete discrimination. It is equivalent to the area under the receiver operating characteristic (ROC) curve. Size of association between the number of PIMRA thresholds attained and total ABC scores, and between total PIMRA scores and total ABC scores was established by calculating Spearman rank correlation coefficients.</p> <hd id="AN0036518945-7">Method 2</hd> <p>Variables were entered into a multivariate regression, with total ABC score as the dependent variable. Age, gender, ABS total score and presence of the triad of social impairments characteristic of autistic spectrum disorder were entered in Block 1. One of three alternative indicators of psychiatric status was entered in Block 2: psychiatric caseness, number of thresholds met or total PIMRA score. At this point, it was possible to conclude (see Results) that psychiatric status was associated with level of challenging behaviour, independently of ABS level and the presence of the triad of social impairments. Therefore, an interaction term, representing the interaction of ABS and psychiatric status was entered in Block 3 to test whether the former moderated the impact on challenging behaviour of the latter. The term was created by taking the product of the standardised values of the variables in question (i.e. the contributing variables were centred before creating the interaction term as recommended by [<reflink idref="bib1" id="ref37">1</reflink>]).</p> <hd id="AN0036518945-8">Results</hd> <p>Significantly higher proportions of participants who met threshold levels for psychiatric caseness were categorised as having severe challenging behaviour within the full sample, within those who had the triad of social impairments in the full sample and within those who did not have the triad of social impairments in the adjusted sample (see Table 2). Overall, risk of having severe challenging behaviour was over four times greater among participants who met threshold levels for psychiatric caseness. Risk was lower but still significantly increased for participants with the triad of social impairments (about twice as great) and higher for those without the triad of social impairments (over 14 times greater). ABC scores were also significantly higher among those who met threshold levels for psychiatric caseness in all three comparisons (see Table 3). Effects size indicators showed a substantial effect within the full sample and those without the triad of social impairments. Effect size was less, although still moderate, for those with the triad of social impairments. There were significant associations between total ABC scores and both the number of PIMRA thresholds attained and total PIMRA scores among the full sample, among those who had the triad of social impairments in the full sample and among those who did not have the triad of social impairments in the adjusted sample (see Table 4). All associations were indicative of medium to large effect sizes according to [<reflink idref="bib10" id="ref38">10</reflink>]) rules of thumb.</p> <p>2 Proportion of participants categorised as having severe challenging behaviour according to psychiatric status, relative risk (RR) and 95% RR confidence intervals (CI)</p> <p> <ephtml> <table><thead valign="bottom"><tr><th><bold>Group</bold></th><th><bold>Categorised as having severe challenging behaviour (%)</bold></th></tr><tr><th><bold>Above threshold</bold></th><th><bold>Below threshold</bold></th><th><bold>Significance</bold></th><th><bold>RR</bold></th><th><bold>Low 95% RR CI</bold></th><th><bold>High 95% RR CI</bold></th></tr></thead><tbody valign="top"><tr><td>Full sample (<italic>n</italic> = 312)</td><td>25.2</td><td>5.9</td><td><italic>χ</italic><sup>2</sup> = 22.9, d.f. = 1, <italic>P</italic> < 0.001</td><td>4.23</td><td>2.13</td><td>8.92</td></tr><tr><td>Sample with triad (<italic>n</italic> = 102)</td><td>40.0</td><td>19.0</td><td><italic>χ</italic><sup>2</sup> = 5.0, d.f. = 1, <italic>P</italic> < 0.05</td><td>2.10</td><td>1.09</td><td>4.23</td></tr><tr><td>Adjusted sample without triad (<italic>n</italic> = 185)</td><td>14.5</td><td>1.0</td><td><italic>χ</italic><sup>2</sup> = 12.7, d.f. = 1, <italic>P</italic> < 0.001</td><td>14.75</td><td>2.58</td><td>88.14</td></tr></tbody></table> </ephtml> </p> <p>3 Mean total Aberrant Behavior Checklist scores according to psychiatric status</p> <p> <ephtml> <table><thead valign="bottom"><tr><th><bold>Group</bold></th><th><bold>Mean total Aberrant Behavior Checklist scores</bold></th></tr><tr><th><bold>Above threshold</bold></th><th><bold>Below threshold</bold></th><th><bold>Significance</bold></th><th><bold>AUROC</bold></th><th><bold>Low 95% AUROC CI</bold></th><th><bold>High 95% AUROC CI</bold></th></tr></thead><tbody valign="top"><tr><td>Full sample (<italic>n</italic> = 312)</td><td>31.7</td><td>15.0</td><td><italic>U</italic> = 6617, <italic>P</italic> < 0.001</td><td>0.27</td><td>0.22</td><td>0.33</td></tr><tr><td>Sample with triad (<italic>n</italic> = 102)</td><td>41.7</td><td>29.3</td><td><italic>U</italic> = 883, <italic>P</italic> < 0.01</td><td>0.35</td><td>0.25</td><td>0.46</td></tr><tr><td>Adjusted sample without triad (<italic>n</italic> = 185)</td><td>24.4</td><td>8.8</td><td><italic>U</italic> = 2078, <italic>P</italic> < 0.001</td><td>0.25</td><td>0.18</td><td>0.32</td></tr></tbody></table> </ephtml> </p> <ulist> <item>5 AUROC, Area under the Receiver Operating Characteristic (ROC) curve; CI, confidence interval.</item> <item>4 Associations between Psychopathology Instrument for Mentally Retarded Adults (PIMRA) Scores and Aberrant Behavior Checklist (ABC) scores, and between the number of PIMRA thresholds attained and ABC scores</item> </ulist> <p> <ephtml> <table><thead valign="bottom"><tr><th><bold>Group</bold></th><th><bold>Association between PIMRA and ABC total scores</bold></th><th><bold>Association between number of PIMRA thresholds and ABC scores</bold></th></tr><tr><th><bold><italic>r</italic><sub>s</sub></bold></th><th><bold>Significance</bold></th><th><bold><italic>r</italic><sub>s</sub></bold></th><th><bold>Significance</bold></th></tr></thead><tbody valign="top"><tr><td>Full sample (<italic>n</italic> = 312)</td><td>0.60</td><td><italic>P</italic> < 0.001</td><td>0.43</td><td><italic>P</italic> < 0.001</td></tr><tr><td>Sample with triad (<italic>n</italic> = 102)</td><td>0.41</td><td><italic>P</italic> < 0.001</td><td>0.32</td><td><italic>P</italic> < 0.001</td></tr><tr><td>Adjusted sample without triad (<italic>n</italic> = 185)</td><td>0.60</td><td><italic>P</italic> < 0.001</td><td>0.48</td><td><italic>P</italic> < 0.001</td></tr></tbody></table> </ephtml> </p> <p>In the regression analysis, age, total ABS scores and presence of the triad of social impairments characteristic of autistic spectrum disorder, but not gender, were found to have significant beta coefficients and thus contributed independently to the prediction of challenging behaviour (see Table 5). Collectively, these variables explained 23% of the variance in ABC scores. All three of the alternative measures of psychiatric status entered in Block 2 had significant beta coefficients (all <emph>P</emph> < 0.001) and contributed significantly and independently to the proportion of variance explained: psychiatric caseness a further 9%, the number of thresholds met a further 19% and total PIMRA score a further 23% of variance. As the latter performed best, it is this variable that is shown in Block 2 in Table 5 and upon which the interaction term with level of adaptive behaviour entered in Block 3 was based. That interaction term had a significant beta weight and added significantly, albeit modestly, to the proportion of variance explained (a further 1%). The final model explained nearly half of the variance in ABC scores, with lower age, presence of the triad of social impairments, low ABS scores and higher PIMRA scores contributing to higher ABC scores.</p> <p>5 Multiple regression coefficients and model summaries for the full sample</p> <p> <ephtml> <table><thead valign="bottom"><tr><th /><th><bold>Beta</bold></th><th><italic><bold>P</bold></italic></th></tr></thead><tbody valign="top"><tr><td>Block 1</td><td>Age</td><td>−0.13</td><td>0.011</td></tr><tr><td>Gender</td><td>0.04</td><td>0.389</td></tr><tr><td>Triad of social impairments</td><td>0.31</td><td>0.000</td></tr><tr><td>ABS score</td><td>−0.20</td><td>0.001</td></tr><tr><td><italic>R</italic><sup>2</sup> = 0.23, adjusted <italic>R</italic><sup>2</sup> = 0.22, <italic>F</italic><sub>4,307</sub> = 22.42, <italic>P</italic> = 0.000</td></tr><tr><td>Blocks 1 & 2</td><td>Age</td><td>−0.16</td><td>0.000</td></tr><tr><td>Gender</td><td>0.04</td><td>0.330</td></tr><tr><td>Triad of social impairments</td><td>0.15</td><td>0.006</td></tr><tr><td>ABS score</td><td>−0.25</td><td>0.000</td></tr><tr><td>PIMRA score</td><td>0.50</td><td>0.000</td></tr><tr><td><italic>R</italic><sup>2</sup> = 0.45, adjusted <italic>R</italic><sup>2</sup> = 0.44, <italic>F</italic><sub>5,306</sub> = 50.19, <italic>P</italic> = 0.000, Δ<italic>R</italic><sup>2</sup> = 0.23, Δ<italic>F</italic><sub>1,306</sub> = 125.05, <italic>P</italic> = 0.000</td></tr><tr><td>Blocks 1–3</td><td>Age</td><td>−0.16</td><td>0.000</td></tr><tr><td>Gender</td><td>0.03</td><td>0.452</td></tr><tr><td>Triad of social impairments</td><td>0.11</td><td>0.046</td></tr><tr><td>ABS score</td><td>−0.29</td><td>0.000</td></tr><tr><td>PIMRA score</td><td>0.52</td><td>0.000</td></tr><tr><td>ABS × PIMRA interaction</td><td>−0.12</td><td>0.005</td></tr><tr><td><italic>R</italic><sup>2</sup> = 0.46, adjusted <italic>R</italic><sup>2</sup> = 0.45, <italic>F</italic><sub>6,305</sub> = 44.07, <italic>P</italic> = 0.000, Δ<italic>R</italic><sup>2</sup> = 0.01, Δ<italic>F</italic><sub>1,305</sub> = 7.85, <italic>P</italic> = 0.005</td></tr></tbody></table> </ephtml> </p> <ulist> <item>6 Δ<emph>R</emph><sups>2</sups> = change in <emph>R</emph><sups>2</sups>, Δ<emph>F</emph> = <emph>F</emph> test of significance for the change in <emph>R</emph><sups>2</sups>.</item> <item>7 ABS, Adaptive Behavior Scale; PIMRA, Psychopathology Instrument for Mentally Retarded Adults.</item> </ulist> <p>As the interaction between ABS and PIMRA scores was significant, further analysis was undertaken to explore the nature of the effect by using the graphical analysis method described by [<reflink idref="bib1" id="ref39">1</reflink>]). Figure 1 shows that higher PIMRA scores are associated with higher ABC scores irrespective of whether ABS scores are low, average or high (i.e. there is a strong main effect for this association). However, the most marked association is when ABS scores were low.</p> <p>Graph: 1 Illustration of the effect of the interaction between Adaptive Behavior Scale (ABS) and Psychopathology Instrument for Mentally Retarded Adults (PIMRA) scores on predicted Aberrant Behavior Checklist (ABC) scores. Predicted ABC scores were derived from the regression line with the constant term and the mean level entered for the age, gender and triad of social impairments terms. ABS low was one SD below the mean, ABS high was one SD above the mean, PIMRA low was one SD below the mean and PIMRA high was one SD above the mean. The ABS–PIMRA interaction term, being calculated from standardised scores was represented by the coefficient multiplied by either 1 (both ABS and PIMRA either below or above the mean) or −1 (one of ABS or PIMRA below the mean, the other above the mean).</p> <hd id="AN0036518945-9">Discussion</hd> <p>The aim was to explore the association between psychiatric status and the occurrence of challenging behaviour, while controlling for level of adaptive behaviour and the occurrence of autistic spectrum disorders. The sample was identified from primary care practices, which served approximately one eighth of the population of Wales. The use of a primary care sample is distinctive and adds potential value to this research, in that the sample is not restricted to the recipients of any particular ID service or services. However, the sample was not randomly selected. Practices nominated adults for the study after they had gained permission to do so. Based on information from 16 practices on the total number of individuals identified as opposed to those referred to the research, it was estimated that a total of about 745 adults would have been identified. The achieved sample constitutes 43% of this estimated total, and there were areas where it was not representative of the population of people with ID as a whole. However, in many important respects concerned with the distribution of age, behavioural characteristics and place of residence, the achieved sample appeared broadly representative of UK ID populations.</p> <p>Diagnostic validity is always a challenge in research such as this. The use of the ABS to characterise degree of disability is considered a strength as it is a fine grain assessment which, although not reflecting IQ directly, is a direct measure of the functional limitations that accompany ID. The sections of the DAS used to assess the triad of social impairments characteristic of autistic spectrum disorders are well established for this purpose. The greatest weakness is the use of a psychiatric screen by which to characterise the participants' psychiatric status. Screening assessments are likely to be over inclusive. The proportion assessed as meeting at least one threshold level indicative of possible mental illness in this study was 45.8%, which is higher than any of the point prevalence rates reported by [<reflink idref="bib11" id="ref40">11</reflink>]). Although not dissimilar to the 40.9% Cooper <emph>et al.</emph> found based on clinical diagnosis, it is considerably higher than the 15.7% based on DSM criteria, an earlier version of which informed the development of the PIMRA. In the present study, the following proportions of the sample attained threshold levels for the individual domains: 4.5% schizophrenia, 12.2% affective disorder, 0% psychosexual disorder, 13.5% adjustment disorder, 24.4% anxiety disorder, 8.3% somatoform disorder, 4.5% personality disorder and 12.2% inappropriate adjustment. It is possible that the procedure for identifying the sample may have contributed to the inflated ascertainment of mental illness in that identification partly relied on medication records. Alternatively, although [<reflink idref="bib11" id="ref41">11</reflink>]) demonstrated that DSM criteria do not include the presence of challenging behaviour or pervasive developmental disorder as indicative of mental illness in themselves, the inflated ascertainment of possible mental illness, particularly reflected in the proportions with adjustment problems, may mean that participants have been included on the basis of behavioural repertoire rather than psychiatric symptomatology. The possibility of there still being a degree of tautology in the relationship between psychiatric status and level of challenging behaviour remains.</p> <p>Aside from this, the study has demonstrated a relationship between psychiatric status and occurrence of challenging behaviour independent of level of adaptive behaviour and presence of autistic spectrum disorder. We did this using two analytic methods. The first attempted to control for confounding variables by comparing groups matched on salient characteristics. Differences and associations within the data were tested for significance by using non‐parametric methods, which make no assumptions about the underlying distribution of the data. However, while similarity of group means and standard deviations was demonstrated for each confounding variable separately, the possibility continues that groups may differ in relation to combinations of variables. The second analytic method employs data at an individual level and therefore is not subject to this limitation. The fact that the two analyses produce similar conclusions suggests a robust relationship between challenging behaviour and psychiatric disorder.</p> <p>The use of relative risk or effect size estimates is a useful addition to the first analytical approach, giving a measure of potency of effect in addition to statistical significance. These suggest that challenging behaviours were very strongly related to psychiatric problems in those without the triad of social impairments, but much less so within the subgroup with the triad of social impairments. This can be interpreted in terms of autistic spectrum disorders having an independent association with level of challenging behaviour, resulting in the proportion of challenging behaviour associated with mental illness being lower. Therefore, challenging behaviours may have utility as diagnostic markers for psychiatric problems in those with ID who do not have autism but may be less useful diagnostically for those with ID and autism.</p> <p>The multivariate analyses suggest a pattern of multiple determination of challenging behaviour. Age during the adult years was a negative predictor of challenging behaviour, the presence of autistic symptoms a positive predictor, and adaptive behaviour a negative predictor. There was also a strong main effect relationship of psychiatric disorder on challenging behaviour. The adaptive behaviour and psychiatric disorder effects also interacted such that the association between psychiatric disorder and challenging behaviour was most pronounced at lower levels of adaptive behaviour. Although this interaction effect formally accounted for only a small proportion of variance in challenging behaviour scores, proportion of variance explained is a notoriously misleading measure in moderated multiple regression analyses where it is difficult to detect statistically significant effects in applied studies ([<reflink idref="bib21" id="ref42">21</reflink>]).</p> <p>The patterns of association found are open to a number of interpretations. They are consistent with the first two hypothesised pathways of effect described by [<reflink idref="bib14" id="ref43">14</reflink>]). The fact that the association was more marked at lower adaptive behaviour supports the proposition that challenging behaviour may represent either the atypical presentation or the secondary features of a psychiatric disorder among people with more severe ID. They may also be consistent with the third of [<reflink idref="bib14" id="ref44">14</reflink>]) hypotheses, namely that psychiatric disorders may act as establishing operations for operant‐maintained challenging behaviours. However, this would depend on evidence that links the risk of operant development of challenging behaviour to severity of ID. [<reflink idref="bib15" id="ref45">15</reflink>]) proposed a three‐level model for the development of stereotypy and self‐injury, which sees the behaviours initially as internal regulation of rhythmic patterns as part of maturation and development, progressing through the modulation of arousal and ending as learned behaviours that have acquired function. This model has not been fully tested, although the latter transition has received some support from research on children with severe ID by [<reflink idref="bib16" id="ref46">16</reflink>]). Once developed, for such behaviours to be maintained requires them to be efficient ([<reflink idref="bib9" id="ref47">9</reflink>]). In terms of response efficiency, challenging behaviours have the advantage of being topographically simple, gross motor movements. Hence, it might be reasonable to hypothesise that they would have a higher likelihood of becoming functional given a more restricted repertoire of other responses that could assume similar functions, particularly fine motor movements or symbolic communication.</p> <p>A further hypothesis is that challenging behaviours and psychiatric status are not directly linked but co‐occur because of underlying biological pathology, which may also give rise to severity of ID and be implicated in the occurrence of autistic spectrum disorder. A great number of genetic conditions give rise to severe ID. It would be surprising for there not to be other neurological sequelae. However, yet another possibility is that the presence of challenging behaviour, particularly in association with severe ID, may increase the likelihood of certain risk factors for mental illness such as social isolation, separation from loved ones, sudden and unplanned life changes, or unsympathetic or ill treatment. All in all, there is a need for prospective research on the aetiologies of mental illness and challenging behaviour and their links to genetic and environmental precursors.</p> <p>In conclusion, despite the need for caution expressed above, this study has reinforced previous findings that psychiatric morbidity among people with ID is associated with higher levels of challenging behaviour. The precise nature and causal direction of the association requires further clarification. Our results are consistent with several hypotheses about the association between psychiatric disorder and challenging behaviours, and also directly support the contention that this association may be strongest in those with more severe ID. Thus, it is too early to reject the proposition that challenging behaviours may be indicative of the presence of psychiatric problems in people with severe ID (cf. [<reflink idref="bib31" id="ref48">31</reflink>]). Our data do not unfortunately help to distinguish between the hypotheses suggested by [<reflink idref="bib14" id="ref49">14</reflink>]) nor other hypotheses discussed here. However, these results do reinforce the need for developmental research to understand the emergence and co‐emergence of challenging behaviours and psychiatric disorder.</p> <p>The understanding of how psychiatric problems might contribute to challenging behaviour (or vice versa) also needs to be part of the clinical appreciation of such behaviour. Assessment needs to be holistic and approaches to challenging behaviour sufficiently inclusive and flexible to bring psychiatric and psychological perspectives together. For example, [<reflink idref="bib14" id="ref50">14</reflink>]) describes the case for viewing repetitive self‐injury among people with severe ID as an atypical presentation of obsessive–compulsive disorder. [<reflink idref="bib6" id="ref51">6</reflink>]) reported that fluoxetine significantly reduced self‐injurious and aggressive behaviours, which had a compulsive nature in seven out of ten participants whereas there were no such changes among six participants who showed non‐compulsive self‐injury or aggression. Moreover, treatment of mental illness may be an effective route to take even when it is only one of a number of possible contributing factors. Affective disorders change the motivational basis for behaviour. Activities usually undertaken may be stripped of positive reinforcement. Termination or avoidance of such activities may become negatively reinforcing. If a person has learned that a particular challenging behaviour deflects demands to engage in activity or removes the need to continue to participate in an activity, episodes of depression and the like may precipitate increases in challenging behaviour. One treatment approach might be to reverse prior learning; another would be to treat the depression. The fact that the common use of antipsychotic medication for people with ID and challenging behaviour is not evidence‐based ([<reflink idref="bib8" id="ref52">8</reflink>]) should not overshadow the need for specific well‐established treatment of well‐defined psychiatric problems.</p> <hd id="AN0036518945-10">Acknowledgements</hd> <p>This research was supported by a grant from the Henry Smith Charity. We would like to thank the participants, their families and the general practices for taking part. We would also like to thank Helen Baxter, Glyn Jones, Kathy Lowe, Rosie Chapman, Brandon Hayward, Jill Patterson, Samantha Brophy, Rebecca Turner, Amanda Meek, William Fraser, Kirsty Pound, James Belcher and Beth Rees for their involvement.</p> <ref id="AN0036518945-11"> <title> Footnotes </title> <blist> <bibl id="bib1" idref="ref37" type="bt">1</bibl> <bibtext> Role of the funding source: The Henry Smith Charity had no involvement in the study design, the collection, analysis and interpretation of data, the writing of the report or the decision to submit the paper for publication. Ethical approval: Ethical approval was provided by the Bro‐Taff, Gwent and Dyfed Powys ethics committees. Competing interests: None.</bibtext> </blist> </ref> <ref id="AN0036518945-12"> <title> References </title> <blist> <bibtext> Aiken L. S. & West S. G. (1991) Multiple Regression: Testing and Interpreting Interactions. Sage, Newbury Park, CA.</bibtext> </blist> <blist> <bibl id="bib2" idref="ref24" type="bt">2</bibl> <bibtext> Aman M. G. & Singh N. N. (1986) The Aberrant Behavior Checklist. Slosson Educational Publications, New York.</bibtext> </blist> <blist> <bibl id="bib3" idref="ref5" type="bt">3</bibl> <bibtext> American Psychiatric Association (2000) Diagnostic and Statistical Manual of Mental Disorders, 4th edn., revised (DSM‐IV‐TR). American Psychiatric Association, Arlington, VA.</bibtext> </blist> <blist> <bibl id="bib4" idref="ref22" type="bt">4</bibl> <bibtext> Baxter H., Lowe K., Houston H., Jones G., Felce D. & Kerr M. (2006) Previously unidentified morbidity in patients with intellectual disability. British Journal of General Practice 56, 93 – 8.</bibtext> </blist> <blist> <bibl id="bib5" idref="ref14" type="bt">5</bibl> <bibtext> Blacher J. & McIntyre L. L. (2006) Syndrome specificity and behavioural disorders in young adults with intellectual disability: cultural differences in family impact. Journal of Intellectual Disability Research 50, 184 – 98.</bibtext> </blist> <blist> <bibl id="bib6" idref="ref51" type="bt">6</bibl> <bibtext> Bodfish J. W. & Madison J. T. (1993) Diagnosis and fluoxetine treatment of compulsive disorder of adults with mental retardation. American Journal on Mental Retardation 98, 360 – 7.</bibtext> </blist> <blist> <bibl id="bib7" idref="ref16" type="bt">7</bibl> <bibtext> Borthwick‐Duffy S. A. (1994) Prevalence of destructive behaviours: a study of aggression, self‐injury and property destruction. In: Destructive Behavior in Developmental Disabilities: Diagnosis and Treatment (eds T. Thompson & D. B. Gray), pp. 3 – 23. Sage, Thousand Oaks, CA.</bibtext> </blist> <blist> <bibl id="bib8" idref="ref52" type="bt">8</bibl> <bibtext> Brylewski J. & Duggan L. (1999) Antipsychotic medication for challenging behaviour in people with intellectual disability: a systematic review of randomized controlled trials. Journal of Intellectual Disability Research 43, 360 – 71.</bibtext> </blist> <blist> <bibl id="bib9" idref="ref47" type="bt">9</bibl> <bibtext> Carr E. G. (1988) Functional equivalence as a mechanism of response generalization. In: Generalization and Maintenance: Life‐style Changes in Applied Settings (eds R. H. Horner, R. L. Koegel & G. Dunlap), pp. 194 – 219. Paul H Brookes, Baltimore, MD.</bibtext> </blist> <blist> <bibtext> Cohen J. (1992) A power primer. Psychological Bulletin 112, 155 – 9.</bibtext> </blist> <blist> <bibtext> Cooper S.‐A., Smiley E., Morrison J., Williamson A. & Allan L. (2007a) Mental ill‐health in adults with intellectual disabilities: prevalence and associated factors. British Journal of Psychiatry 190, 27 – 35.</bibtext> </blist> <blist> <bibtext> Cooper S.‐A., Smiley E., Finlayson A., Jackson L., Allan L., Williamson A. et al. (2007b) Prevalence, incidence and factors predictive of mental ill‐health in adults with profound intellectual disabilities. Journal of Applied Research in Intellectual Disabilities 20, 493 – 501.</bibtext> </blist> <blist> <bibtext> Einfeld S. L. & Tonge B. J. (1999) Observations on the use of the ICD‐10 guide for mental retardation. Journal of Intellectual Disability Research 43, 408 – 12.</bibtext> </blist> <blist> <bibtext> Emerson E. (2001) Challenging Behaviour: Analysis and Intervention on People with Severe Intellectual Disabilities. Cambridge University Press, Cambridge.</bibtext> </blist> <blist> <bibtext> Guess D. & Carr E. (1991) The emergence and maintenance of stereotypy and self‐injury. American Journal on Mental Retardation 96, 299 – 319.</bibtext> </blist> <blist> <bibtext> Hall S., Oliver C. & Murphy G. (2001) Early development of self‐injurious behavior: an empirical study. American Journal on Mental Retardation 106, 189 – 99.</bibtext> </blist> <blist> <bibtext> Hastings R. P. & Mount R. H. (2001) Early correlates of behavioural and emotional problems in children and adolescents with severe intellectual disabilities: a preliminary study. Journal of Applied Research in Intellectual Disabilities 14, 381 – 91.</bibtext> </blist> <blist> <bibtext> Holden B. & Gitlesen J. P. (2003) Prevalence and psychiatric symptoms in adults with mental retardation and challenging behaviour. Research in Developmental Disabilities 24, 323 – 32.</bibtext> </blist> <blist> <bibtext> Holmes N., Shah A. & Wing L. (1982) The Disability Assessment Schedule: a brief screening device for use with the mentally retarded. Psychological Medicine 2, 879 – 90.</bibtext> </blist> <blist> <bibtext> Lowe K., Felce D. & Blackman D. (1995) People with learning disabilities and challenging behaviour: the characteristics of those referred and not referred to specialist teams. Psychological Medicine 25, 595 – 603.</bibtext> </blist> <blist> <bibtext> McClelland G. H. & Judd C. M. (1993) Statistical difficulties of detecting interactions and moderator effects. Psychological Bulletin 114, 376 – 90.</bibtext> </blist> <blist> <bibtext> Marston G. M., Perry D. W. & Roy A. (1997) Manifestations of depression in people with intellectual disability. Journal of Intellectual Disability Research 41, 476 – 80.</bibtext> </blist> <blist> <bibtext> Matson J. (1988) The Psychopathology Instrument for Mentally Retarded Adults. IDS Publishing Co., Worthington, OH.</bibtext> </blist> <blist> <bibtext> Moss S., Emerson E., Kiernan C., Turner S., Hatton C. & Alborz A. (2000) Psychiatric symptoms in adults with learning disability and challenging behaviour. British Journal of Psychiatry 177, 452 – 6.</bibtext> </blist> <blist> <bibtext> Newcombe R. G. (2006) Confidence intervals for an effect size measure based on the Mann–Whitney statistic. Part 1: general issues and tail‐area‐based methods. Statistics in Medicine 25, 543 – 57.</bibtext> </blist> <blist> <bibtext> Nihira K., Leland H. & Lambert N. (1993) Adaptive Behavior Scale‐Residential and Community, 2nd edn. Pro‐ed, Austin, TX.</bibtext> </blist> <blist> <bibtext> Robertson J., Emerson E., Pinkney L., Caesar E., Felce D., Meek A. et al. (2004) Quality & costs of community‐based residential supports for people with mental retardation and challenging behavior. American Journal on Mental Retardation 109, 332 – 44.</bibtext> </blist> <blist> <bibtext> Rojahn J., Matson J. L., Naglieri J. A. & Mayville E. (2004) Relationships between psychiatric conditions and behavioural problems among adults with mental retardation. American Journal on Mental Retardation 109, 21 – 33.</bibtext> </blist> <blist> <bibtext> Royal College of Psychiatrists (2001) DC‐LD: Diagnostic Criteria for Psychiatric Disorders for Use with Adults with Learning Disabilities/Mental Retardation, (Occasional Paper OP48). Gaskell, London.</bibtext> </blist> <blist> <bibtext> Sturmey P. (1995) DSM‐IIIR and persons with dual diagnosis: conceptual issues and strategies for future research. Journal of Intellectual Disability Research 39, 357 – 64.</bibtext> </blist> <blist> <bibtext> Tsiouris J. A., Mann R., Patti P. J. & Sturmey P. (2003) Challenging behaviours should not be considered as depressive equivalents in individuals with intellectual disability. Journal of Intellectual Disability Research 47, 14 – 21.</bibtext> </blist> <blist> <bibtext> Whitaker S. & Read S. (2006) The prevalence of psychiatric disorders among people with intellectual disabilities: an analysis of the literature. Journal of Applied Research in Intellectual Disabilities 19, 330 – 45.</bibtext> </blist> <blist> <bibtext> Wing L. & Gould J. (1979) Severe impairments of social interaction and associated abnormalities in children: epidemiology and classification. Journal of Autism and Developmental Disorders 9, 11 – 29.</bibtext> </blist> <blist> <bibtext> World Health Organization (1993) The ICD‐10 Classification of Mental and Behavioural Disorders: Diagnostic Criteria for Research. World Health Organization, Geneva.</bibtext> </blist> </ref> <aug> <p>By D. Felce; M. Kerr and R. P. Hastings</p> <p>Reported by Author; Author; Author</p> </aug> <nolink nlid="nl1" bibid="bib11" firstref="ref1"></nolink> <nolink nlid="nl2" bibid="bib29" firstref="ref3"></nolink> <nolink nlid="nl3" bibid="bib34" firstref="ref4"></nolink> <nolink nlid="nl4" bibid="bib30" firstref="ref6"></nolink> <nolink nlid="nl5" bibid="bib13" firstref="ref7"></nolink> <nolink nlid="nl6" bibid="bib32" firstref="ref9"></nolink> <nolink nlid="nl7" bibid="bib12" firstref="ref10"></nolink> <nolink nlid="nl8" bibid="bib14" firstref="ref12"></nolink> <nolink nlid="nl9" bibid="bib17" firstref="ref13"></nolink> <nolink nlid="nl10" bibid="bib24" firstref="ref17"></nolink> <nolink nlid="nl11" bibid="bib18" firstref="ref18"></nolink> <nolink nlid="nl12" bibid="bib28" firstref="ref19"></nolink> <nolink nlid="nl13" bibid="bib22" firstref="ref20"></nolink> <nolink nlid="nl14" bibid="bib31" firstref="ref21"></nolink> <nolink nlid="nl15" bibid="bib23" firstref="ref23"></nolink> <nolink nlid="nl16" bibid="bib33" firstref="ref25"></nolink> <nolink nlid="nl17" bibid="bib26" firstref="ref26"></nolink> <nolink nlid="nl18" bibid="bib20" firstref="ref31"></nolink> <nolink nlid="nl19" bibid="bib27" firstref="ref32"></nolink> <nolink nlid="nl20" bibid="bib19" firstref="ref33"></nolink> <nolink nlid="nl21" bibid="bib25" firstref="ref36"></nolink> <nolink nlid="nl22" bibid="bib10" firstref="ref38"></nolink> <nolink nlid="nl23" bibid="bib21" firstref="ref42"></nolink> <nolink nlid="nl24" bibid="bib15" firstref="ref45"></nolink> <nolink nlid="nl25" bibid="bib16" firstref="ref46"></nolink>
Header DbId: eric
DbLabel: ERIC
An: EJ828609
AccessLevel: 3
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 0
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: A General Practice-Based Study of the Relationship between Indicators of Mental Illness and Challenging Behaviour among Adults with Intellectual Disabilities
– Name: Language
  Label: Language
  Group: Lang
  Data: English
– Name: Author
  Label: Authors
  Group: Au
  Data: <searchLink fieldCode="AR" term="%22Felce%2C+D%2E%22">Felce, D.</searchLink><br /><searchLink fieldCode="AR" term="%22Kerr%2C+M%2E%22">Kerr, M.</searchLink><br /><searchLink fieldCode="AR" term="%22Hastings%2C+R%2E+P%2E%22">Hastings, R. P.</searchLink>
– Name: TitleSource
  Label: Source
  Group: Src
  Data: <searchLink fieldCode="SO" term="%22Journal+of+Intellectual+Disability+Research%22"><i>Journal of Intellectual Disability Research</i></searchLink>. Mar 2009 53(3):243-254.
– Name: Avail
  Label: Availability
  Group: Avail
  Data: Blackwell Publishing. 350 Main Street, Malden, MA 02148. Tel: 800-835-6770; Tel: 781-388-8599; Fax: 781-388-8232; e-mail: customerservices@blackwellpublishing.com; Web site: http://www.blackwellpublishing.com/jnl_default.asp
– Name: PeerReviewed
  Label: Peer Reviewed
  Group: SrcInfo
  Data: Y
– Name: PhysDesc
  Label: Physical Description
  Group: PhysDesc
  Data: PDF
– Name: Pages
  Label: Page Count
  Group: Src
  Data: 12
– Name: DatePubCY
  Label: Publication Date
  Group: Date
  Data: 2009
– Name: TypeDocument
  Label: Document Type
  Group: TypDoc
  Data: Journal Articles<br />Reports - Research
– Name: Subject
  Label: Descriptors
  Group: Su
  Data: <searchLink fieldCode="DE" term="%22Mental+Retardation%22">Mental Retardation</searchLink><br /><searchLink fieldCode="DE" term="%22Mental+Disorders%22">Mental Disorders</searchLink><br /><searchLink fieldCode="DE" term="%22Adults%22">Adults</searchLink><br /><searchLink fieldCode="DE" term="%22Antisocial+Behavior%22">Antisocial Behavior</searchLink><br /><searchLink fieldCode="DE" term="%22Correlation%22">Correlation</searchLink><br /><searchLink fieldCode="DE" term="%22Pervasive+Developmental+Disorders%22">Pervasive Developmental Disorders</searchLink><br /><searchLink fieldCode="DE" term="%22Adjustment+%28to+Environment%29%22">Adjustment (to Environment)</searchLink><br /><searchLink fieldCode="DE" term="%22Multiple+Regression+Analysis%22">Multiple Regression Analysis</searchLink>
– Name: DOI
  Label: DOI
  Group: ID
  Data: 10.1111/j.1365-2788.2008.01131.x
– Name: ISSN
  Label: ISSN
  Group: ISSN
  Data: 0964-2633
– Name: Abstract
  Label: Abstract
  Group: Ab
  Data: Background: Existing studies tend to show a positive association between mental illness and challenging behaviour among adults with intellectual disabilities (ID). However, whether the association is direct or artefactual is less clear. The purpose was to explore the association between psychiatric status and level of challenging behaviour, while controlling for adaptive behaviour and occurrence of autistic spectrum disorders. Methods: Data were collected on the age, gender, adaptive and challenging behaviour, social impairment and psychiatric status of 312 adults with ID. Participants were divided according to psychiatric status, group equivalence in adaptive behaviour and the presence of autistic spectrum disorders achieved, and differences in challenging behaviour explored. In addition, multiple regression was used to examine the association between psychiatric status and challenging behaviour after controlling for other participant characteristics and to test whether the interaction between psychiatric status and adaptive behaviour added significantly to explanation. Results: Challenging behaviour was higher among participants meeting threshold levels on the psychiatric screen. The regression analysis confirmed the association and demonstrated an interaction between total score on the psychiatric screen and level of adaptive behaviour. This moderated effect showed the relationship between psychiatric status and challenging behaviour to be stronger at lower adaptive behaviour. Conclusions: This study reinforces previous findings that psychiatric morbidity among people with ID is associated with higher levels of challenging behaviour and supports predictions that this association is more pronounced for people with severe ID. The precise nature and causal direction of the association requires further clarification. However, the understanding of how psychiatric problems might contribute to challenging behaviour needs to be part of the clinical appreciation of such behaviour.
– Name: AbstractInfo
  Label: Abstractor
  Group: Ab
  Data: As Provided
– Name: Ref
  Label: Number of References
  Group: RefInfo
  Data: 34
– Name: DateEntry
  Label: Entry Date
  Group: Date
  Data: 2009
– Name: AN
  Label: Accession Number
  Group: ID
  Data: EJ828609
PLink https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=eric&AN=EJ828609
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.1111/j.1365-2788.2008.01131.x
    Languages:
      – Text: English
    PhysicalDescription:
      Pagination:
        PageCount: 12
        StartPage: 243
    Subjects:
      – SubjectFull: Mental Retardation
        Type: general
      – SubjectFull: Mental Disorders
        Type: general
      – SubjectFull: Adults
        Type: general
      – SubjectFull: Antisocial Behavior
        Type: general
      – SubjectFull: Correlation
        Type: general
      – SubjectFull: Pervasive Developmental Disorders
        Type: general
      – SubjectFull: Adjustment (to Environment)
        Type: general
      – SubjectFull: Multiple Regression Analysis
        Type: general
    Titles:
      – TitleFull: A General Practice-Based Study of the Relationship between Indicators of Mental Illness and Challenging Behaviour among Adults with Intellectual Disabilities
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Felce, D.
      – PersonEntity:
          Name:
            NameFull: Kerr, M.
      – PersonEntity:
          Name:
            NameFull: Hastings, R. P.
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 01
              M: 03
              Type: published
              Y: 2009
          Identifiers:
            – Type: issn-print
              Value: 0964-2633
          Numbering:
            – Type: volume
              Value: 53
            – Type: issue
              Value: 3
          Titles:
            – TitleFull: Journal of Intellectual Disability Research
              Type: main
ResultId 1