Physical & Occupational Therapy in Pediatrics, 35(1):1–12, 2015 C 2015 by Informa Healthcare USA, Inc. Available online at http://informahealthcare.com/potp DOI: 10.3109/01942638.2014.904471
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ORIGINAL RESEARCH
Assessing Sensory Processing Problems in Children With and Without Attention Deficit Hyperactivity Disorder Beth Pfeiffer1 , Brian P. Daly2 , Elizabeth G. Nicholls3 , & Dominic F. Gullo4 1
Associate Professor, Department of Rehabilitation Sciences, Temple University, Philadelphia, PA, USA, 2 Assistant Professor, Department of Psychology, Drexel University, Philadelphia, PA, USA, 3 Doctoral Student, Department of Psychology, Drexel University, Philadelphia, PA, USA, 4 Professor, Department of Education, Drexel University, Philadelphia, PA, USA
ABSTRACT. Aims: This exploratory study investigated whether children with attention-deficit/hyperactivity disorder (ADHD) are at greater risk than children without ADHD for problems with sensory processing and if certain sensory systems are more closely associated with the core symptoms of ADHD, specifically inattention and hyperactivity/impulsivity. Methods: The sample included 20 children with ADHD and 27 children without ADHD, ages 5 to 10 years. Assessments included the Sensory Processing Measure-Home Form and the Conners 3rd edition-Parent Short Form. Results: After controlling for age, children with ADHD exhibited more sensory processing problems on all scales of the Sensory Processing Measure with small to medium effect sizes observed (η2 = .27 to .61). For children with ADHD, the Social Participation (r = .50) and Planning and Ideas (r = .73) subtests of the Sensory Processing Measure were significantly associated with hyperactivity/impulsivity, but not with inattention on the subtests of the Conners Parent Short Form. Conclusion: The results suggest the importance of assessing sensory processing issues in children with ADHD to guide in the intervention process. KEYWORDS. ADHD, ADHD subtypes, children, hyperactivity/impulsivity, inattention, sensory processing
In clinical practice, occupational therapists and physical therapists are likely to treat children diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD). Therapists are also likely to evaluate and treat problems associated with sensory processing, as recent data suggest that one in six children with ADHD display sensory symptoms severe enough to negatively impact aspects of everyday life functions (Ben-Sasson et al., 2009). Despite the prevalence of ADHD and sensory Address correspondence to: Dr Beth Pfeiffer, PhD, OTR/L, BCP, Department of Rehabilitation Sciences, Temple University, 3307 North Broad Street, Philadelphia, PA 19140, USA (E-mail: [email protected]). (Received 22 July 2013; accepted 5 March 2014)
1
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processing dysfunction (SPD) in children, the cooccurrence of these problems has not been well studied (Ghanizadeh, 2011). Sensory processing refers to the way an individual integrates sensory information and manages adaptive responses to the sensory environment to engage in meaningful daily life activities (Johnson-Ecker & Parham, 2000). Children who evidence sensory processing challenges are at heightened risk for poor social skills, low self-confidence and self-esteem (Parham & Mailloux, 2001), as well as compromised quality of life and well-being (Dunn, 2001). Moreover, findings from additional studies demonstrate that deficits in sensory processing occur at elevated rates in children with ADHD as compared to typically developing peers (Cheung & Siu, 2009; Dunn & Bennett, 2002; Mangeot et al., 2001; Yochman et al., 2004). Although these findings are generally consistent, there remain notable gaps and limitations in the research that are important to consider. For example, when examining sensory processing behaviors, previous studies have used the Sensory Profile (SP; Dunn, 1999). While the SP examines core aspects of sensory processing such as auditory, visual, tactile, and vestibular processing (Dunn, 1999; McIntosh et al., 1999), this measure does not evaluate important higher-level cognitive functions such as social behaviors and motor planning abilities (praxis), two important functional aspects of daily living for children. Children who are successful in their social behaviors demonstrate multiple positive outcomes (Eisenberg et al., 2006), while those who struggle are at risk for a host of negative outcomes including increased rates of emotional problems, alienation from peers, poor academic performance, and a higher incidence of involvement in the criminal justice system (National Association of School Psychologists, 2002). Motor planning, or praxis, is the “ability to conceptualize, plan, and organize movements in order to complete unfamiliar motor tasks” (Parham & Ecker, 2007, p. 27). While there is some emerging evidence to indicate that motor functions such as equilibrium, postural control, and balance performance are more impaired in children with ADHD than among typically developing peers (Iwanga et al., 2006; Shum & Pang, 2009), the association between praxis and ADHD has yet to be investigated despite the fact that motor abnormalities (e.g., physical restlessness) are among the hallmark symptoms of the disorder (American Psychiatric Association, 2000). Taken together, these findings suggest the need for more specific investigation of social participation and praxis in children with ADHD. The Sensory Processing Measure (SPM; Parham & Ecker, 2007) not only examines specific sensory systems but also evaluates social participation and planning and ideas (praxis). To our knowledge, no published studies have used the SPM to examine sensory processing issues in children diagnosed with ADHD. Research to date also has failed to identify whether a distinct pattern of sensory processing impairments exists in relation to the core deficits in ADHD. While several researchers have posited that children with sensory processing deficits display higher levels of inattention, distractibility, over-arousal, and impulsivity than do youth with normal sensory processing (Dunn, 1997; 1999; McIntosh et al., 1999), the theoretical overlap between these behavioral characteristics and the primary symptoms of ADHD (inattention and hyperactivity/impulsivity) have been studied in only two investigations. In one study of a sample of preschool children, children
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Sensory Processing and ADHD
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with greater sensory deficits were more likely to display higher levels of hyperactive behavior (Yochman et al., 2004). In a study of boys 6 to 10 years of age, boys with ADHD had more sensory processing difficulties than boys without ADHD, although no significant differences were found in the pattern of sensory processing problems between subtype of ADHD (Engel-Yeger & Ziv-On, 2011). While these preliminary findings provide initial support for a relationship between sensory issues and ADHD symptoms, there remains a need to more clearly examine and delineate specific relationships between the core symptoms of ADHD and select sensory processing difficulties. The goals of this exploratory study were to: (1) investigate whether children with ADHD experience higher levels of impairment from sensory processing problems relative to children without ADHD; and, (2) investigate which sensory systems are associated with inattention and hyperactivity/impulsivity, the core symptoms of ADHD.
METHODS Participants Twenty parents of children with a diagnosis of ADHD and 27 parents of children without a diagnosis of ADHD participated in the study. The children without ADHD had no other developmental delays or diagnoses as indicated on the demographic forms completed by their parents. None of the children without ADHD received supportive services. The children diagnosed with ADHD included 15 boys and 5 girls, 5–10 years of age (M = 9.1, SD = 1.3). The children without ADHD included 13 boys and 14 girls, 5–10 years of age (M = 8.3, SD = 1.6). The age range of 5–10 years was selected as the SPM is standardized for this age range. The study was approved by the Institutional Review Board at Temple University and all parents provided informed consent. A convenience sample of parents of children with ADHD was recruited several ways including: (a) a pediatricians’ office; (b) an ADHD information fair; and, (c) a Web site specific to childhood ADHD. For the eight parents of children with ADHD recruited through the pediatricians’ office, chart reviews were completed by the pediatrician and his staff to identify children with a current and primary Axis 1 diagnosis of ADHD based on the DSM-IV-TR criteria (APA, 2000) and the information was provided to parents. Parent participants not recruited through the pediatrician’s office provided confirmation on the demographic information form that their child had a diagnosis of ADHD provided by a health professional. Parents of children without ADHD were recruited through information and fliers posted in: (a) pediatricians’ offices; (b) community settings; and, (c) a local elementary school. Parents contacted the researchers and additional information was provided to parents by members of the research team or through a letter provided to the parents that explained the study. If parents were interested in participating in the study, they were asked to complete the written informed consent and return it to the research team. Exclusion criteria for all children included a diagnosis of a pervasive developmental disorder (PDD) such as Autism Spectrum Disorder as these children are at
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higher risk of sensory disorders (Cheung & Siu, 2009; Miller et al., 2012). For children with ADHD, a diagnosis of PDD was determined by chart review completed by the pediatrician or his staff when available or through the demographic questionnaire completed by parents. Two children with ADHD were excluded based on a diagnosis of a PDD. No formal psychiatric assessment was conducted on children without ADHD; instead, the absence of a pervasive developmental disorder and any other developmental delay or diagnoses was determined through parent report on the demographic questionnaire. No children without ADHD were excluded due to a PDD or other diagnoses. Twelve children diagnosed with ADHD were being treated with psychotropic medication. No children without ADHD were being treated with any medication. Demographic characteristics of the participants are presented in Table 1. Chi-square analyses revealed no significant differences between groups in age
TABLE 1. Demographics for Children With and Without Attention-Deficit/Hyperactivity Disorder (ADHD)
Demographic Gender Male Female Age (in years) Diagnosis ADHD Additional/Other diagnosis No Medications ADHD None Ethnicity African-American Asian Caucasian Hispanic/Latino Native American Other School placement Regular education Special education Learning support Combined Other Regular education with 504 or IEP Services received Psychology or psychiatry Behavioral Physical therapy Speech–language Occupational therapy Other None IEP = individualized education plan.
Children with ADHD (n = 20) n (%)
Children without ADHD (n = 27) n (%)
15 (75.0) 5 (25.0) 9.1 (1.3)
13 (48.1) 14 (51.9) 8.3 (1.6)
17 (85.0) 3 (15.0) 0 (0)
0 (0) 0 (0) 0 (0)
12 (60.0) 8 (40.0)
0 (0) 27 (100.0)
3 (15.0) 0 (0) 12 (60.0) 3 (15.0) 0 (0) 2 (10.0)
3 (11.1) 6 (22.2) 17 (63.0) 0 (0) 1 (3.7) 0 (0)
8 (40.0) 1 (5.0) 2 (10.0) 2 (10.0) 1 (5.0) 6 (30.0)
24 (88.9) 0 (0) 0 (0) 0 (0) 3 (11.1) 0 (0)
9 (45.0) 2 (10.0) 0 (0) 2 (10.0) 0 (0) 7 (35.0) 7 (35.0)
0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 27 (100)
Sensory Processing and ADHD
5
or gender. However, there was a significant difference in race/ethnicity between children with and without ADHD. The group without ADHD included more Asian-American children (χ 2 = 12.34, p < .05).
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Measures Demographic Form. The form included open-ended questions on the child’s age, gender, diagnosis, and medications. Questions also asked about ethnic background of the child (African-American, Asian, Caucasian, Latino/a, Native American, or Other), school placement (i.e., regular education with or without supports, resource room, special education), and special education services that the child receives (i.e., psychological supports, occupational, physical, and/or speech therapy, behavioral support services). Sensory Processing Measure-Home Form (SPM; Parham & Ecker, 2007) is a norm-referenced assessment completed by a parent or primary caregiver that measures sensory processing in the five sensory systems of visual, auditory, tactile, proprioceptive, and vestibular functioning, as well as higher-level sensory processing functions including social participation and praxis. The SPM includes a total of 75 items. There are four response options for each item: never, occasionally, frequently, always that correspond with the frequency of the behavior during the past month. A total standard score is obtained as well as separate standard scores for seven sensory systems and areas: social participation, vision, hearing, touch, body awareness, balance and motion, planning and ideas. Scores that fall within one standard deviation of the mean for each category represent “Typical processing,” one to two standard deviations above the mean indicates “Some Problems,” and scores two standard deviations above the mean represent “Definite Dysfunction” (Parham & Ecker, 2007). The Home Form was used for the purposes of this study as parents completed the questionnaire. Internal consistency was established with Cronbach’s alpha ranging from .77 to .95 and strong test–retest reliability was demonstrated with estimates ranging from .94 to .98 (Parham & Ecker, 2007; Parham et al., 2007). Conners 3rd Edition-Parent Short Form (Conners, 2008) is a standardized rating scale of parent’s observations about their child’s behavior. The purpose of the instrument is to assess symptoms of ADHD and common comorbid problems. The Parent rating form contains the following scales: inattention, hyperactivity/impulsivity, learning problems, executive function, aggression, and peer relations. Forty-two items are rated on a scale of 0 to 3. Parents are instructed to base their ratings on the frequency of the behavior in the past month. Response options include the following: 0 = Not true at all (Never, Seldom); 1 = Just a little true (Occasionally); 2 = Pretty much true (Often, Quite a bit); or, 3 = Very much true (Very often, Very infrequently). Raw scores are converted to T-scores with a mean of 50 and a standard deviation of 10. Norms are provided by age and gender. A T-score between 40 to 59 suggests appropriate levels of behavior, 60–69 suggests elevated levels of problems, while a T-score of 70 or above represents clinically significant problems. For the purposes of this study, we only examined the inattention and hyperactivity/impulsivity scales as they directly correspond with the core symptoms of ADHD. Standardization based on a large, representative national sample revealed internal consistency coefficients on the content scales of the parent form
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that ranged from .83 to .94 (Conners, 2008). Specific internal consistency coefficients for the inattention and hyperactivity/impulsivity scales were .93 and .94, respectively (Conners, 2008). Adequate test–retest reliability was demonstrated for the parent form with estimates ranging from .72 to .98 (Conners, 2008).
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Procedure After receipt of the signed consent form, parents of children with or without ADHD received via mail an introductory letter with brief instructions on how to complete the packet, the demographic form, the Sensory Processing MeasureHome Form, and the Conners-Parent Short Form with instructions to mail the packet back to the research team. Parents that returned completed packets received a gift card in the amount of $20.00. Data Analyses Data analyses were conducted using Statistical Package for Social Sciences (SPSS) version 19.0. To determine whether there was a higher occurrence of sensory processing problems among children diagnosed with ADHD, a one-way multivariate analysis of covariance (MANCOVA) was conducted using group as the independent variable and the seven SPM subscales as dependent variables. Prior to conducting the MANCOVA, Pearson product correlation coefficients were calculated among the SPM subscales. All of the subscales of the SPM were significantly correlated (p < .001), therefore justifying using MANCOVA as the method of analysis. Age in months was used as the covariate in order to control for potential developmental differences among the children. To determine whether there was a difference in sensory processing problems among children with ADHD who were taking medication compared to those who were not, a one-way MANCOVA was conducted using medication status as the independent variable and the seven SPM subscales as dependent variables with age in months as the covariate. This analysis sought to determine if the use of medication altered sensory processing patterns. Additionally, analysis of covariance (ANCOVA) were conducted to determine whether scores on the inattention and hyperactivity/impulsivity subscales of the Conners-Parent Short Form differed between children with ADHD taking medication (N = 12) as compared to children with ADHD not taking medication (N = 8). For these analyses, age in months was the covariate. Among children with ADHD, bivariate correlations were calculated between SPM subscale scores and inattention and hyperactivity/impulsivity subscale scores of the Conners-Parent Short Form. These correlations were performed to determine whether there is an association between sensory processing problems and the core symptoms of ADHD. RESULTS Sensory Processing Measure-Home Form The one-way MANCOVA for SPM subscale scores revealed a significant multivariate group effect [F (7,38) = 24.93, p < .001, η2 = .71]. Power to detect the effect
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was 1.00. Children with and children without ADHD differed in sensory processing. Given the significance of the overall multivariate test, the univariate tests for each of the six SPM subscales were conducted with a Bonferroni adjustment to control for the type I error rate often found when performing multiple comparisons. The Bonferroni-adjusted alpha level of .007 per test was used (.05/7). Table 2 presents the means, standard deviations, and univariate tests of significance for the SPM subscales. For each of the SPM subscales, children with ADHD had a higher mean score compared to children without ADHD. Eta squared (η2 ), an effect size estimate varied from .27 to .61. According to Cohen (1992), interpretation is as follows: small (.20), medium (.50), and large (.80); therefore, the effect size varied from small to medium. Regarding interpretative classification, the total SPM score of 12 (60%) children with ADHD indicated “some problems” or “definite dysfunction.” In contrast, the total SPM score of one (4%) child without ADHD indicated “some problems” and no child had “definite dysfunction.” The one-way MANCOVA indicated that there was no significant difference in SPM subscale scores between children with ADHD who took medication and those who did not [F (7,11) = 1.26, p = .356]. Conners-Parent Short Form One-way ANCOVA indicated there was a significant main effect for the Hyperactivity/Impulsivity subscale controlling for age [F (1,44) = 104.88, p < .001]. Children with ADHD had a higher mean score (M = 81.4. SD = 11.4) than children without ADHD (M = 48.4, SD = 9.7). One-way ANCOVA also indicated a significant main effect for the Inattention subscale controlling for age [F (1,44) = 99.90, p < .001]. Children with ADHD had a higher mean score (M = 78.6, SD = 10.6) than children without ADHD (M = 48.4, SD = 9.2). According to the interpretative guidelines for the Hyperactivity/Impulsivity subscale, 17 children with ADHD had scores that indicated clinically significant problems, one child had a score indicating at-risk for problems, and two children had scores in the appropriate levels of behavior range. In contrast, 23 children without ADHD had scores in the appropriate levels of behavior range, two had scores indicating clinically significant problems, and two had scores indicating at-risk for problems. For the Inattention subscale, 17 children with ADHD had scores that
TABLE 2. Comparison of Subscale Scores for the Sensory Processing Measure-Home Form Between Children with ADHD and Children without ADHD Subscale
Children with ADHD Mean (SD)
Children without ADHD Mean (SD)
F DF (1,44)
p
η2
Social Visual Hearing Touch Body Balance Planning
62.0 (9.6) 56.7 (11.6) 59.6 (9.7) 60.0 (9.4) 62.0 (7.6) 57.0 (10.5) 65.1 (8.3)
45.0 (7.4) 44.8 (6.5) 45.6 (4.6) 45.3 (7.2) 43.2 (5.2) 46.5 (7.1) 44.9 (6.2)
44.7∗∗ 19.0∗∗ 44.2∗∗ 35.9∗∗ 101.8∗∗ 15.4∗∗ 81.3∗∗
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ORIGINAL RESEARCH
Assessing Sensory Processing Problems in Children With and Without Attention Deficit Hyperactivity Disorder Beth Pfeiffer1 , Brian P. Daly2 , Elizabeth G. Nicholls3 , & Dominic F. Gullo4 1
Associate Professor, Department of Rehabilitation Sciences, Temple University, Philadelphia, PA, USA, 2 Assistant Professor, Department of Psychology, Drexel University, Philadelphia, PA, USA, 3 Doctoral Student, Department of Psychology, Drexel University, Philadelphia, PA, USA, 4 Professor, Department of Education, Drexel University, Philadelphia, PA, USA
ABSTRACT. Aims: This exploratory study investigated whether children with attention-deficit/hyperactivity disorder (ADHD) are at greater risk than children without ADHD for problems with sensory processing and if certain sensory systems are more closely associated with the core symptoms of ADHD, specifically inattention and hyperactivity/impulsivity. Methods: The sample included 20 children with ADHD and 27 children without ADHD, ages 5 to 10 years. Assessments included the Sensory Processing Measure-Home Form and the Conners 3rd edition-Parent Short Form. Results: After controlling for age, children with ADHD exhibited more sensory processing problems on all scales of the Sensory Processing Measure with small to medium effect sizes observed (η2 = .27 to .61). For children with ADHD, the Social Participation (r = .50) and Planning and Ideas (r = .73) subtests of the Sensory Processing Measure were significantly associated with hyperactivity/impulsivity, but not with inattention on the subtests of the Conners Parent Short Form. Conclusion: The results suggest the importance of assessing sensory processing issues in children with ADHD to guide in the intervention process. KEYWORDS. ADHD, ADHD subtypes, children, hyperactivity/impulsivity, inattention, sensory processing
In clinical practice, occupational therapists and physical therapists are likely to treat children diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD). Therapists are also likely to evaluate and treat problems associated with sensory processing, as recent data suggest that one in six children with ADHD display sensory symptoms severe enough to negatively impact aspects of everyday life functions (Ben-Sasson et al., 2009). Despite the prevalence of ADHD and sensory Address correspondence to: Dr Beth Pfeiffer, PhD, OTR/L, BCP, Department of Rehabilitation Sciences, Temple University, 3307 North Broad Street, Philadelphia, PA 19140, USA (E-mail: [email protected]). (Received 22 July 2013; accepted 5 March 2014)
1
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2
Pfeiffer et al.
processing dysfunction (SPD) in children, the cooccurrence of these problems has not been well studied (Ghanizadeh, 2011). Sensory processing refers to the way an individual integrates sensory information and manages adaptive responses to the sensory environment to engage in meaningful daily life activities (Johnson-Ecker & Parham, 2000). Children who evidence sensory processing challenges are at heightened risk for poor social skills, low self-confidence and self-esteem (Parham & Mailloux, 2001), as well as compromised quality of life and well-being (Dunn, 2001). Moreover, findings from additional studies demonstrate that deficits in sensory processing occur at elevated rates in children with ADHD as compared to typically developing peers (Cheung & Siu, 2009; Dunn & Bennett, 2002; Mangeot et al., 2001; Yochman et al., 2004). Although these findings are generally consistent, there remain notable gaps and limitations in the research that are important to consider. For example, when examining sensory processing behaviors, previous studies have used the Sensory Profile (SP; Dunn, 1999). While the SP examines core aspects of sensory processing such as auditory, visual, tactile, and vestibular processing (Dunn, 1999; McIntosh et al., 1999), this measure does not evaluate important higher-level cognitive functions such as social behaviors and motor planning abilities (praxis), two important functional aspects of daily living for children. Children who are successful in their social behaviors demonstrate multiple positive outcomes (Eisenberg et al., 2006), while those who struggle are at risk for a host of negative outcomes including increased rates of emotional problems, alienation from peers, poor academic performance, and a higher incidence of involvement in the criminal justice system (National Association of School Psychologists, 2002). Motor planning, or praxis, is the “ability to conceptualize, plan, and organize movements in order to complete unfamiliar motor tasks” (Parham & Ecker, 2007, p. 27). While there is some emerging evidence to indicate that motor functions such as equilibrium, postural control, and balance performance are more impaired in children with ADHD than among typically developing peers (Iwanga et al., 2006; Shum & Pang, 2009), the association between praxis and ADHD has yet to be investigated despite the fact that motor abnormalities (e.g., physical restlessness) are among the hallmark symptoms of the disorder (American Psychiatric Association, 2000). Taken together, these findings suggest the need for more specific investigation of social participation and praxis in children with ADHD. The Sensory Processing Measure (SPM; Parham & Ecker, 2007) not only examines specific sensory systems but also evaluates social participation and planning and ideas (praxis). To our knowledge, no published studies have used the SPM to examine sensory processing issues in children diagnosed with ADHD. Research to date also has failed to identify whether a distinct pattern of sensory processing impairments exists in relation to the core deficits in ADHD. While several researchers have posited that children with sensory processing deficits display higher levels of inattention, distractibility, over-arousal, and impulsivity than do youth with normal sensory processing (Dunn, 1997; 1999; McIntosh et al., 1999), the theoretical overlap between these behavioral characteristics and the primary symptoms of ADHD (inattention and hyperactivity/impulsivity) have been studied in only two investigations. In one study of a sample of preschool children, children
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Sensory Processing and ADHD
3
with greater sensory deficits were more likely to display higher levels of hyperactive behavior (Yochman et al., 2004). In a study of boys 6 to 10 years of age, boys with ADHD had more sensory processing difficulties than boys without ADHD, although no significant differences were found in the pattern of sensory processing problems between subtype of ADHD (Engel-Yeger & Ziv-On, 2011). While these preliminary findings provide initial support for a relationship between sensory issues and ADHD symptoms, there remains a need to more clearly examine and delineate specific relationships between the core symptoms of ADHD and select sensory processing difficulties. The goals of this exploratory study were to: (1) investigate whether children with ADHD experience higher levels of impairment from sensory processing problems relative to children without ADHD; and, (2) investigate which sensory systems are associated with inattention and hyperactivity/impulsivity, the core symptoms of ADHD.
METHODS Participants Twenty parents of children with a diagnosis of ADHD and 27 parents of children without a diagnosis of ADHD participated in the study. The children without ADHD had no other developmental delays or diagnoses as indicated on the demographic forms completed by their parents. None of the children without ADHD received supportive services. The children diagnosed with ADHD included 15 boys and 5 girls, 5–10 years of age (M = 9.1, SD = 1.3). The children without ADHD included 13 boys and 14 girls, 5–10 years of age (M = 8.3, SD = 1.6). The age range of 5–10 years was selected as the SPM is standardized for this age range. The study was approved by the Institutional Review Board at Temple University and all parents provided informed consent. A convenience sample of parents of children with ADHD was recruited several ways including: (a) a pediatricians’ office; (b) an ADHD information fair; and, (c) a Web site specific to childhood ADHD. For the eight parents of children with ADHD recruited through the pediatricians’ office, chart reviews were completed by the pediatrician and his staff to identify children with a current and primary Axis 1 diagnosis of ADHD based on the DSM-IV-TR criteria (APA, 2000) and the information was provided to parents. Parent participants not recruited through the pediatrician’s office provided confirmation on the demographic information form that their child had a diagnosis of ADHD provided by a health professional. Parents of children without ADHD were recruited through information and fliers posted in: (a) pediatricians’ offices; (b) community settings; and, (c) a local elementary school. Parents contacted the researchers and additional information was provided to parents by members of the research team or through a letter provided to the parents that explained the study. If parents were interested in participating in the study, they were asked to complete the written informed consent and return it to the research team. Exclusion criteria for all children included a diagnosis of a pervasive developmental disorder (PDD) such as Autism Spectrum Disorder as these children are at
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higher risk of sensory disorders (Cheung & Siu, 2009; Miller et al., 2012). For children with ADHD, a diagnosis of PDD was determined by chart review completed by the pediatrician or his staff when available or through the demographic questionnaire completed by parents. Two children with ADHD were excluded based on a diagnosis of a PDD. No formal psychiatric assessment was conducted on children without ADHD; instead, the absence of a pervasive developmental disorder and any other developmental delay or diagnoses was determined through parent report on the demographic questionnaire. No children without ADHD were excluded due to a PDD or other diagnoses. Twelve children diagnosed with ADHD were being treated with psychotropic medication. No children without ADHD were being treated with any medication. Demographic characteristics of the participants are presented in Table 1. Chi-square analyses revealed no significant differences between groups in age
TABLE 1. Demographics for Children With and Without Attention-Deficit/Hyperactivity Disorder (ADHD)
Demographic Gender Male Female Age (in years) Diagnosis ADHD Additional/Other diagnosis No Medications ADHD None Ethnicity African-American Asian Caucasian Hispanic/Latino Native American Other School placement Regular education Special education Learning support Combined Other Regular education with 504 or IEP Services received Psychology or psychiatry Behavioral Physical therapy Speech–language Occupational therapy Other None IEP = individualized education plan.
Children with ADHD (n = 20) n (%)
Children without ADHD (n = 27) n (%)
15 (75.0) 5 (25.0) 9.1 (1.3)
13 (48.1) 14 (51.9) 8.3 (1.6)
17 (85.0) 3 (15.0) 0 (0)
0 (0) 0 (0) 0 (0)
12 (60.0) 8 (40.0)
0 (0) 27 (100.0)
3 (15.0) 0 (0) 12 (60.0) 3 (15.0) 0 (0) 2 (10.0)
3 (11.1) 6 (22.2) 17 (63.0) 0 (0) 1 (3.7) 0 (0)
8 (40.0) 1 (5.0) 2 (10.0) 2 (10.0) 1 (5.0) 6 (30.0)
24 (88.9) 0 (0) 0 (0) 0 (0) 3 (11.1) 0 (0)
9 (45.0) 2 (10.0) 0 (0) 2 (10.0) 0 (0) 7 (35.0) 7 (35.0)
0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 27 (100)
Sensory Processing and ADHD
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or gender. However, there was a significant difference in race/ethnicity between children with and without ADHD. The group without ADHD included more Asian-American children (χ 2 = 12.34, p < .05).
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Measures Demographic Form. The form included open-ended questions on the child’s age, gender, diagnosis, and medications. Questions also asked about ethnic background of the child (African-American, Asian, Caucasian, Latino/a, Native American, or Other), school placement (i.e., regular education with or without supports, resource room, special education), and special education services that the child receives (i.e., psychological supports, occupational, physical, and/or speech therapy, behavioral support services). Sensory Processing Measure-Home Form (SPM; Parham & Ecker, 2007) is a norm-referenced assessment completed by a parent or primary caregiver that measures sensory processing in the five sensory systems of visual, auditory, tactile, proprioceptive, and vestibular functioning, as well as higher-level sensory processing functions including social participation and praxis. The SPM includes a total of 75 items. There are four response options for each item: never, occasionally, frequently, always that correspond with the frequency of the behavior during the past month. A total standard score is obtained as well as separate standard scores for seven sensory systems and areas: social participation, vision, hearing, touch, body awareness, balance and motion, planning and ideas. Scores that fall within one standard deviation of the mean for each category represent “Typical processing,” one to two standard deviations above the mean indicates “Some Problems,” and scores two standard deviations above the mean represent “Definite Dysfunction” (Parham & Ecker, 2007). The Home Form was used for the purposes of this study as parents completed the questionnaire. Internal consistency was established with Cronbach’s alpha ranging from .77 to .95 and strong test–retest reliability was demonstrated with estimates ranging from .94 to .98 (Parham & Ecker, 2007; Parham et al., 2007). Conners 3rd Edition-Parent Short Form (Conners, 2008) is a standardized rating scale of parent’s observations about their child’s behavior. The purpose of the instrument is to assess symptoms of ADHD and common comorbid problems. The Parent rating form contains the following scales: inattention, hyperactivity/impulsivity, learning problems, executive function, aggression, and peer relations. Forty-two items are rated on a scale of 0 to 3. Parents are instructed to base their ratings on the frequency of the behavior in the past month. Response options include the following: 0 = Not true at all (Never, Seldom); 1 = Just a little true (Occasionally); 2 = Pretty much true (Often, Quite a bit); or, 3 = Very much true (Very often, Very infrequently). Raw scores are converted to T-scores with a mean of 50 and a standard deviation of 10. Norms are provided by age and gender. A T-score between 40 to 59 suggests appropriate levels of behavior, 60–69 suggests elevated levels of problems, while a T-score of 70 or above represents clinically significant problems. For the purposes of this study, we only examined the inattention and hyperactivity/impulsivity scales as they directly correspond with the core symptoms of ADHD. Standardization based on a large, representative national sample revealed internal consistency coefficients on the content scales of the parent form
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Pfeiffer et al.
that ranged from .83 to .94 (Conners, 2008). Specific internal consistency coefficients for the inattention and hyperactivity/impulsivity scales were .93 and .94, respectively (Conners, 2008). Adequate test–retest reliability was demonstrated for the parent form with estimates ranging from .72 to .98 (Conners, 2008).
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Procedure After receipt of the signed consent form, parents of children with or without ADHD received via mail an introductory letter with brief instructions on how to complete the packet, the demographic form, the Sensory Processing MeasureHome Form, and the Conners-Parent Short Form with instructions to mail the packet back to the research team. Parents that returned completed packets received a gift card in the amount of $20.00. Data Analyses Data analyses were conducted using Statistical Package for Social Sciences (SPSS) version 19.0. To determine whether there was a higher occurrence of sensory processing problems among children diagnosed with ADHD, a one-way multivariate analysis of covariance (MANCOVA) was conducted using group as the independent variable and the seven SPM subscales as dependent variables. Prior to conducting the MANCOVA, Pearson product correlation coefficients were calculated among the SPM subscales. All of the subscales of the SPM were significantly correlated (p < .001), therefore justifying using MANCOVA as the method of analysis. Age in months was used as the covariate in order to control for potential developmental differences among the children. To determine whether there was a difference in sensory processing problems among children with ADHD who were taking medication compared to those who were not, a one-way MANCOVA was conducted using medication status as the independent variable and the seven SPM subscales as dependent variables with age in months as the covariate. This analysis sought to determine if the use of medication altered sensory processing patterns. Additionally, analysis of covariance (ANCOVA) were conducted to determine whether scores on the inattention and hyperactivity/impulsivity subscales of the Conners-Parent Short Form differed between children with ADHD taking medication (N = 12) as compared to children with ADHD not taking medication (N = 8). For these analyses, age in months was the covariate. Among children with ADHD, bivariate correlations were calculated between SPM subscale scores and inattention and hyperactivity/impulsivity subscale scores of the Conners-Parent Short Form. These correlations were performed to determine whether there is an association between sensory processing problems and the core symptoms of ADHD. RESULTS Sensory Processing Measure-Home Form The one-way MANCOVA for SPM subscale scores revealed a significant multivariate group effect [F (7,38) = 24.93, p < .001, η2 = .71]. Power to detect the effect
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Sensory Processing and ADHD
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was 1.00. Children with and children without ADHD differed in sensory processing. Given the significance of the overall multivariate test, the univariate tests for each of the six SPM subscales were conducted with a Bonferroni adjustment to control for the type I error rate often found when performing multiple comparisons. The Bonferroni-adjusted alpha level of .007 per test was used (.05/7). Table 2 presents the means, standard deviations, and univariate tests of significance for the SPM subscales. For each of the SPM subscales, children with ADHD had a higher mean score compared to children without ADHD. Eta squared (η2 ), an effect size estimate varied from .27 to .61. According to Cohen (1992), interpretation is as follows: small (.20), medium (.50), and large (.80); therefore, the effect size varied from small to medium. Regarding interpretative classification, the total SPM score of 12 (60%) children with ADHD indicated “some problems” or “definite dysfunction.” In contrast, the total SPM score of one (4%) child without ADHD indicated “some problems” and no child had “definite dysfunction.” The one-way MANCOVA indicated that there was no significant difference in SPM subscale scores between children with ADHD who took medication and those who did not [F (7,11) = 1.26, p = .356]. Conners-Parent Short Form One-way ANCOVA indicated there was a significant main effect for the Hyperactivity/Impulsivity subscale controlling for age [F (1,44) = 104.88, p < .001]. Children with ADHD had a higher mean score (M = 81.4. SD = 11.4) than children without ADHD (M = 48.4, SD = 9.7). One-way ANCOVA also indicated a significant main effect for the Inattention subscale controlling for age [F (1,44) = 99.90, p < .001]. Children with ADHD had a higher mean score (M = 78.6, SD = 10.6) than children without ADHD (M = 48.4, SD = 9.2). According to the interpretative guidelines for the Hyperactivity/Impulsivity subscale, 17 children with ADHD had scores that indicated clinically significant problems, one child had a score indicating at-risk for problems, and two children had scores in the appropriate levels of behavior range. In contrast, 23 children without ADHD had scores in the appropriate levels of behavior range, two had scores indicating clinically significant problems, and two had scores indicating at-risk for problems. For the Inattention subscale, 17 children with ADHD had scores that
TABLE 2. Comparison of Subscale Scores for the Sensory Processing Measure-Home Form Between Children with ADHD and Children without ADHD Subscale
Children with ADHD Mean (SD)
Children without ADHD Mean (SD)
F DF (1,44)
p
η2
Social Visual Hearing Touch Body Balance Planning
62.0 (9.6) 56.7 (11.6) 59.6 (9.7) 60.0 (9.4) 62.0 (7.6) 57.0 (10.5) 65.1 (8.3)
45.0 (7.4) 44.8 (6.5) 45.6 (4.6) 45.3 (7.2) 43.2 (5.2) 46.5 (7.1) 44.9 (6.2)
44.7∗∗ 19.0∗∗ 44.2∗∗ 35.9∗∗ 101.8∗∗ 15.4∗∗ 81.3∗∗
