The mood of the moment: Early detection and measurement of anxiety and depression in children and adolescents in a Dutch public health setting

In the Netherlands, child (mental) health care professionals screen for anxiety and depressive disorders in schoolchildren and adolescents and refer them to an effective intervention when needed. Screening is defined as the identification of a disease at an early stage or a previously unrecognized disease by the application of tests. Screening has two aims: a humanitarian and an economical aim. Although screening seems beneficial, it can cause harm as well. To prevent adverse consequences of screening, Wilson & Jungner described ten preconditions for screening in a public health setting. We scrutinized three of these preconditions in relation to the screening for an anxiety or depressive disorder in Dutch schoolchildren and adolescents, namely: 1) there must be an important health problem; 2) there must be a recognizable early symptomatic stage; and 3) there must be a suitable test. To examine whether anxiety and depressive disorders are important health problems in Dutch youth, we quantified the disease burden of anxiety and depressive disorders in 53,894 Dutch secondary school pupils. We quantified disease burden unadjusted and adjusted for comorbidities, as well as at individual and population level. At population level, both anxiety and depression yielded the greatest disease burden compared with eating disorders, substance use disorders, and somatic illnesses, and therefore, we concluded that anxiety and depressive disorders are important health problems for screening. Definitions of an early symptomatic stage of a depressive disorder are various: some describe it as transdiagnostic, while others describe it as moderate depression. In addition, the specific symptoms that play an important role in the development of a depressive disorder are still unknown. Therefore, we explored the association of age with 11 individual depression symptoms and 14 core anxiety symptoms and their interrelations in girls and boys separately. We found that depression symptoms showed more and/or stronger associations with other depression symptoms than with anxiety symptoms, and these associations increased with age. Age was, in particular, strongly associated with energy-related depression symptoms, like “having no energy” or “feeling tired”, in girls. These symptoms, next to “feeling sad or empty”, also showed the most and strongest associations with other depression symptoms, and these associations increased with age. We therefore suggested that these depression symptoms might play a central role in the development of depressive symptomatology in girls. To be suitable for the Dutch public health screening at schools, a test needs to meet several conditions: 1) the test should be a self-report questionnaire; 2) the questionnaire should measure an early stage of anxiety and depressive disorders and/or anxiety and depressive disorders in itself; 3) the questionnaire should be suitable for Dutch schoolchildren and adolescents aged 8 to 18 years; 4) the questionnaire should be suitable for screening and monitoring, and it is desirable that measurements can be standardized; and 5) the questionnaire should be feasible. We examined the psychometric properties of two kinds of self-report questionnaires: 1) the short versions of the Revised Child Anxiety and Depression Scale (RCADS), which are based on classical test theory; and 2) the PROMIS® pediatric item banks, short forms, and computerized adaptive tests Anxiety and Depressive Symptoms, which are based on item response theory. We concluded that the Dutch-Flemish PROMIS pediatric short forms Anxiety and Depressive Symptoms are preferable for assessing and monitoring anxiety and depression in Dutch schoolchildren and adolescents, based on the higher test accuracy over a broader range of the anxiety and depression constructs, as well as on the shortness. We furthered standardizing measurements for research purposes by linking the RCADS-25 scores to the PROMIS pediatric item banks Anxiety and Depressive Symptoms T-scores.