After our recent coverage on how biomarker can improve the accuracy of ADHD diagnosis, a new study on Attention Deficit Hyperactive Disorder (ADHD) seems to have sparked some more controversy as it is considered by a few critics as potentially misleading. Yet, many others vouch for its ability to improve the accuracy of ADHD diagnosis.
About 7% of children around the world are likely to have Attention Deficit Hyperactive Disorder (ADHD), as per the study conducted by Centre for Research in Evidence-based Practice, Australia’s Bond University. The study drew data from 175 previous studies conducted for a period of 36 years. These studies included over a million children from North America and Europe. When this data was compiled, the worldwide ADHD prevalence estimate stood at 7.2 percent and with a range of 6.7 to 7.8 percent.
Rae Thomas, a senior research fellow at the Bond University and lead author of the study, said the “prevalence estimates acts like an anchor”. The problem with ADHD diagnosis is that, public health officials are uncertain whether there is an over or under diagnosis of the disorder in their state. Thomas believes this estimation would help the officials to determine the nature of the diagnosis.
Rae said, “When people would hear the number, they will think this is much more or much less than what we expected”. Depending on the outcome, the officials might want to see why there was an over or a misdiagnosis. According to the study, the estimation might act as a benchmark to determine the accuracy of ADHD diagnosis in small towns as well as large countries.
Thomas, however, acknowledged that the standard of 7.2 percent may be a little higher than the factual ADHD position because many of diagnoses that they studied were conducted without a doctor’s supervision. In other words, many studies used a checklist of symptoms rather than conducting a relevant ADHD test. Many children never acknowledged the symptoms on the checklist because their ADHD symptoms did not affect their normal life. Consequentially, they were never diagnosed with ADHD.
Critics: Benchmark could be misleading
Critics said the benchmark stated by Thomas and team could be misleading. According to them, the 175 studies used by the researchers were not uniform. Different studies used different methods and criteria to determine attention deficit in a child. Moreover, some of the study results were as old as three decades. Undoubtedly, the understanding of and method to determine ADHD have undergone a massive change over these years, and so has the options around ADHD treatment and medication.
Dr. Eyal Shemesh, chief of Behavioural and Developmental Health, Kravis Children’s Hospital, New York City, said Thomas herself agreed that the average estimate varied between the several versions of Diagnostic and Statistical Manual of Mental Disorders, a manual considered as ‘bible’ by the mental health professionals. The estimate varied depending on the evaluation method and setting of the research. “If this is so, then any attempt to look at a specific community in relation to the estimate would be wrong”, points out Dr. Shemesh.
Moreover, Dr. Shemesh said if 4 percent of children in any state was suffering from ADHD, then the health officials would think there was an under diagnosis. However, if the percentage rose to 17, the officials would consider it to be a case of overdiagnosis. In both the cases, the reality might be different from what the officials conclude.
Supporters: A thorough study
Dr. Aaron Krasner, service chief of Adolescent Transitional Living, Silver Hill Hospital, Connecticut considered the estimate to be “as accurate as anyone could probably make it out to be”. The head of Centre for Paediatric Behavioural Health, Cleveland Clinic Paediatric Institute, Michael Manos thought the study was a thorough and comprehensive one. He said the range of 6.7 to 7.8 percent provided in the study should be the used to determine the accuracy of ADHD diagnosis in every community, state, and town.