At 12 years of age, 1 of 19 boys and 1 of 48 girls were registered with hyperkinetic disorder in Norwegian specialist health services. The percentages of children with the diagnosis were stable in the years 2008–2016 for Norway as a whole. The percentages are slightly higher in Norway than in Sweden, Denmark and Finland (12), but correspond with the estimate of 3.4 % in a meta-analysis of 41 studies from 27 countries (13). The percentages receiving medication are at the same level as in Sweden and Denmark, but higher than in Finland (5).
As previously reported, there are substantial variations among the counties. The counties at the top have percentages that are four times as high as the county at the bottom. These variations cannot be explained by differences in gender distribution among those who receive the diagnosis or by the average age at the time of diagnosis. The most likely explanation is regional differences in diagnostic practice. Similar differences among counties have also been previously shown for autism spectrum disorder (4).
The findings from the medical record review indicate that hyperkinetic disorder is often less well documented than other chronic conditions, e.g. cerebral palsy (14). Nor does the Norwegian Patient Registry have information about who has ‘grown out of’ the diagnosis. We also know from previous studies that many children who meet the criteria for psychiatric diagnoses have not been in contact with specialist health services (6). Thus, we cannot use our findings to estimate the actual prevalence of hyperkinetic disorder in the child population in Norway.
From the medical record reviews, we concluded that the diagnosis had not been reliably documented in half of the cases. It is important to emphasise that we have not conducted an independent diagnostic assessment with our own clinical examination of the children. Symptoms consistent with hyperkinetic disorder were recorded for many children, but the information was too scant to reach a conclusion or there was a lack of differential diagnostic assessments. For the majority of those who did not have reliably documented diagnoses, however, there were clear indications that they did not meet the diagnostic criteria. This could indicate that some children are diagnosed with hyperkinetic disorder without actually having it.
Inadequate differential diagnostic assessment and evaluation was the most important reason that diagnoses were not reliably documented. Our assessments were based on all the information found in the medical record, and a lack of one or more assessment components did not automatically result in a conclusion of inadequate differential diagnostics. However, these inadequacies often occur because a standardised psychiatric interview with a broad survey of symptoms was not conducted. Another widespread deficiency in the differential diagnostics was that learning disabilities were not mapped or assessed. Cognitive ability and developmental testing was often not carried out even though learning disabilities were mentioned in both the referral and the anamnesis. In other cases, cognitive ability tests were conducted and clear indications of learning disability or delayed development were found, but the diagnostic assessment did not take this into account. Some medical records contained information about other circumstances in the child’s life that could help to explain the symptoms, such as divorce, serious illness of a parent, parental neglect, abuse or bullying. Learning disabilities, delayed development or difficult circumstances in the child’s life do not exclude the child from having hyperkinetic disorder, but there was often no discussion of what these problems meant for the child’s symptoms and functioning.
The national guideline provides little direction and does not set clear requirements as to what should be included in an assessment of hyperkinetic disorder. As such, it does not provide adequate guidance to those conducting the assessments. We believe this is one reason why many of the diagnoses are poorly documented in the medical records.
Another problem is the brief, imprecise definition of the actual diagnosis in ICD-10, which does not provide specific diagnostic criteria (3). All research on hyperkinetic disorder is based on the diagnostic criteria developed for use in research, and it is therefore important that these criteria are also used in clinical practice (2). Use of the research criteria was part of the diagnostic procedure at many of the institutions we visited. In our view, these diagnostic criteria should also be included in the national guideline, as they provide good and essential support for diagnosing the disorder.
In addition, our impression is that there is a need to improve the quality of the observations of children carried out by specialist health services. The reports from the school observations usually contained only information about the symptoms of hyperkinetic disorder and not information about other factors that could affect the child’s behaviour, such as the classroom environment, organisation of the teaching, and the interaction between the teacher and pupil. Unfortunately, there are no well-evaluated methods for observations of this kind.
Another important experience from the medical record review was that we seldom found information about how the children and parents perceived the problems, the type of help they needed and how they dealt with the diagnosis. It was the kindergarten or school that usually wanted the referral. Our protocol contained no formal survey of involvement from the parents and children. A lack of such information in the medical records makes it uncertain whether the families were given the opportunity for user involvement to which they are entitled (9).
The review of medical records had some weaknesses. We could not analyse the reasons for the county-wise differences because the number of participants per county was too small. Since we only visited clinics in specialist mental health services, we cannot comment on the diagnostics employed at somatic hospitals or by private contract specialists. Many medical records were reviewed by only one expert, which may have made the conclusions vulnerable to subjectivity. Ideally, two experts should have reviewed all the records.
The proportion of children with F90 diagnoses from the specialist health service is lower in the Norwegian Mother and Child Cohort Study than among the general Norwegian childhood population (15). Nonetheless, we believe that our findings are representative for how assessment and diagnosis of hyperkinetic disorder are carried out in specialist mental health services for children and adolescents in Norway.