Case Definition in Epidemiologic Studies of AD/HD
Introduction
Attention-deficit/hyperactivity disorder (AD/HD) is the most common neurobehavioral disorder of childhood 1, 2. It is often chronic in nature, with symptoms which may continue into adulthood. AD/HD is a significant public health concern and represents a costly public health problem 3, 4, 5.
Epidemiologic studies of AD/HD help to address important, but not yet agreed upon, issues related to AD/HD frequency, distributions, and determinants. To address these closely interrelated components requires clearly described and applied AD/HD definitional and assessment methods. Goldman et al. (6) stated that a combination of different types of information (e.g., from several sources, careful examination, appropriate testing, several visits, teacher's reports, a multidisciplinary team approach) is needed to establish the diagnosis of AD/HD. Our proposed research model of identifying AD/HD cases resembles, to a certain degree, current recommended clinical practice (7). A combination of different types of information is required to identify an AD/HD case and most importantly, to avoid overlooking a case for both clinical and research purposes. This article provides details of the methods used in retrospectively identifying and defining incident cases of AD/HD utilizing a population-based birth cohort and the unique resources of the Rochester Epidemiology Project (REP) (8).
Section snippets
Study Setting
Rochester, Minnesota, is located 90 miles southeast of Minneapolis-St. Paul, the closest major urban center. Using census data from 1990, the years the children from this birth cohort were in school, there were 70,745 residents who were 96% white, fairly young (75% ≤ 45 years old), and primarily middle class. With the exception of the place of employment (predominantly health care and computer industries), characteristics of the Rochester population are similar to those of the US white
Results
Among our population-based birth cohort of 5718 children, we identified 379 AD/HD incidence cases using research criteria for AD/HD case definition (Table 2). Of the 379, only 31 (8.2%) moved prior to age 16. The display of numbers of AD/HD cases who satisfied five different combinations of three different categories of information is given in Table 1. Of particular interest were the 228 AD/HD cases who met DSM-IV criteria and the 151 AD/HD cases who did not meet DSM-IV criteria. The median
Discussion
Population-based epidemiologic studies of AD/HD are limited in numbers. Most of the AD/HD research is based on clinic-referred samples of children 17, 18, which may not reflect the spectrum of AD/HD in the population at large. Therefore, population-based, non-referred samples of children with AD/HD are critically needed in order to increase our understanding of AD/HD and increase the generalizability and comparability among studies 4, 16, 19. A population-based birth cohort is a powerful tool
Conclusion
In summary, epidemiologic studies of AD/HD and other developmental and psychiatric disorders, even though difficult and challenging, are feasible when properly planned and implemented. Our approach of developed research criteria for defining AD/HD cases by combining three different categories of information (meets DSM-IV criteria, positive questionnaire results, and recorded clinical diagnosis of AD/HD) is especially appropriate for retrospective, population-based research with reliable,
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Childhood Attention-Deficit/Hyperactivity Disorder, Sex, and Obesity: A Longitudinal Population-Based Study
2016, Mayo Clinic ProceedingsCitation Excerpt :Attention-deficit/hyperactivity disorder incidents were identified by applying research criteria to the 1961 children (34% of the birth cohort) from our birth cohort who had any recorded behavioral or learning concerns. Study subjects were defined as having research-identified ADHD incident cases (n=379) if their school and/or medical records included various combinations of the following 3 categories of information: (1) meets criteria for ADHD from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision; (2) positive ADHD questionnaire results; (3) documented clinical diagnosis of ADHD (with or without specific subtype).22 For each participant with ADHD, we randomly selected 2 age- and sex-matched controls without ADHD from the birth cohort after excluding those with severe intellectual disability.
Incidence of enuresis and encopresis among children with attention-deficit/hyperactivity disorder in a population-based birth cohort
2013, Academic PediatricsCitation Excerpt :We have previously published descriptions of the identification of the 5718 members of the 1976 to 1982 birth cohort in Rochester, Minnesota, who remained in the community at least until 5 years of age and who were included as subjects for this study.1,15,16
Attention-deficit/hyperactivity disorder after early exposure to procedures requiring general anesthesia
2012, Mayo Clinic ProceedingsCitation Excerpt :Alternatively, because the requirement for an IEP-EBD captures a broad spectrum of behaviors of widely differing etiologies, one can postulate that the significant association between procedures requiring anesthesia and ADHD may reflect an effect on the risk for core aspects of ADHD (inattention, hyperactivity, and impulsivity) but not on associated severe behavior problems that trigger the need for IEP-EBD. Limitations of analyses using this birth cohort have been extensively discussed.14,15,42 To highlight the most salient limitation, as mentioned previously in this article, we cannot distinguish between the effects of anesthesia per se and the potential effects of the procedure or surgery accompanying the anesthesia.
Co-occurring Mental Disorders in Transitional Aged Youth With Substance Use Disorders – A Narrative Review
2022, Frontiers in Psychiatry
This project was supported by research grant HD29745 and AR30582 from the Public Health Service of the National Institutes of Health (Bethesda, MD) and Mayo Foundation (Rochester, MN).