Background characteristics, comorbidity, cognitive and social functioning, and parenting practices.
Background
Attention-Deficit/Hyperactivity Disorder (ADHD) is a disorder that affects a child or adult’s ability to sustain attention. There are many theories of what may cause the behaviors most often associated with ADHD. In general, research has identified this as a neurobiological disorder that can be treated with medication such as Ritalin. The neurobiological predisposing factors can be increased by family and school-related factors. For example, if a child lives in a home with constant conflict, the anxiety related to the intensity of arguing among the parents may increase the behavioral symptoms that the teacher will see in school.
In Janaury of 2002 an International Consensus Paper (156 k pdf)* was published on ADHD. It addresses concerns expressed by those who say ADHD does not exist.
Most studies on ADHD have looked at research samples that are comprised most often of male subjects. To a large extent this is because boys are more often diagnosed with ADHD. In part this may be due to the fact that boys more often externalize, or act out frustrations and behaviors. This behavior is more disruptive in the classroom and thus teachers are more likely to suggest to the parents that there is a problem. It seems that only girls with pronounced impairments due to ADHD are referred for help.
Recent discussions have begun to focus on the impact of ADHD in girls as compared to boys. Hinshaw’s review of relevant research suggested that girls with ADHD display more speech and language problems than boys as well a more significant impact on cognitive, or intellectual, abilities. Girls also seemed to have more problems with substance abuse and other “comorbid” disorders and problems with peer relations.
The purpose of the study was to look at the difference between girls with a diagnosis of ADHD-both combined and inattentive type- and a comparison group of girls who did not have ADHD.
Method
Summer research programs were conducted in 1997, 1998, and 1999. Recruitment of girls to participate came from many sources. All testing was done in non-medicated conditions. Intelligence (WISC-III) and academic achievement scores (WIAT) were obtained. Personality variables and parenting styles were also measured using detailed questionnaires.
The sample was from a ethnically diverse population of girls ranging in age from 6-12. Girls with an IQ less than 70, overt neurological damage, psychosis, pervasive developmental disorder, or medical conditions that prevented their participation in camp were excluded from the population studied.
Hypotheses
Four specific hypotheses, or research questions, were investigated:
- Girls with ADHD would display impairments, relative to comparison girls, on cognitive and achievement measures as well as on indicators of peer status and show higher rates of other psychiatric disorders;
- In keeping with interactive and transactional etiologic and risk models, such background characteristics as adoption status and child abuse, as well as developmental factors like speech and language delay, would be more pronounced in the girls with ADHD;
- Parents of the ADHD sample would rate their parenting practices as more harsh and authoritarian, and as less authoritative than parents of the comparison girls;
- Girls in the inattentive group (relative to the combined type) would show less amounts of disruptive comorbidity and peer rejection, histories of greater speech and language problems, lower general cognitive abilities, lower degrees of authoritarian parenting.
Results
- No significant differences were found between the groups of girls with ADHD and non ADHD in terms of age, family income, maternal education, ethnicity, etc.
- Both ADHD groups had far higher rates of inclusion in special education programs, grade retention, and parental reports of early speech and language problems than girls in the non ADHD population. Adoption was also found at a higher rate in the ADHD groups.
- Comorbid factors, or the existence of another disorder along with the diagnoses ADHD, were also found. Oppositional Defiant Disorder (ODD) and Conduct Disorder (CD) were found at a higher rate in girls with ADHD. Girls with combined types were more likely to show these behaviors than girls with Inattentive ADHD type.
- Inattentive ADHD type showed more social isolation than the combined type and more than girls without ADHD.
- Girls with ADHD scored lower than comparisons on measures of IQ and current reading and math achievement. Scores for girls with ADHD were also lower on the Freedom from Distractility Index score than on other index scores for the ADHD group.
Variable A. Combined (n=93) B. Inattentive (n=47) C. Comparison (n=88) WISC-III Verbal Comprehension Index Score 100.6102.8113.7WISC-III Perceptual Organization 100.7100.1108.9WISC-III Freedom From Distractibility 98.096.3109.6WISC-III Processing Speed 100.299.4108.1WIAT Basic Reading 102.1101.1112.0WIAT Math Reasoning 97.397.9109.1Hinshaw, 2002, page 1093.
- Parenting style of girls with ADHD combined showed greater incidence of authoritarian and overwhelmed/unsure styles than the comparison girls. Inattentive girls were in the middle.
Bottom line
The study shows the value of looking at how girls with ADHD differ from girls without ADHD. The social experience of boys and girls has been shown to be different in research. If studies of the gender impact simply compare how boys and girls with ADHD perform it does not give a clear picture of the impact of ADHD of girls.
To fully understand the implications of this study it is important to read more about the sample, how the research was conducted, and the author’s notations of limitations of the current study.
Further information on this topic is also available in their companion study that appears in the same Journal of Clinical and Consulting Psychology. This discussion looks at the neuropsychological performance in relation to subtypes and individual classifications.