Functional somatic disorders (FSD) are common conditions characterized by persistent patterns of physical symptoms that cannot be better explained by other physical or mental conditions. The conditions may cause severe impairment for the patients who are often characterized by impaired physical and mental health, lower social status, and poor labour market association.~In 2005, it was estimated that FSD accounted for 3% of hospitalizations and 10-20% of health care expenses in Denmark, and a newer Danish primary care study has shown patients with FSD to have higher annual health care costs compared with conventionally-defined conditions. In foreign nations, studies in clinical samples have shown increased direct and indirect health care costs of FSD which showed a dose-response relationship with severity of the FSD. One Canadian population-based study found increased health care use and costs in children, adolescents, and young adults with a first health record diagnosis of somatic symptom and related disorders. Even though these previous studies provide valuable knowledge to the field of FSD, their methodology may give rise to bias, i.e. inclusion of highly selected patient samples, the use of various diagnostic criteria for defining FSD, and the establishment of FSD by means of self-report. Evidently, studies investigating the socioeconomic burden in terms of direct health care use and costs of FSD in a randomly obtained population-based sample using solid methodology such as validated symptom criteria and diagnostic interviews for establishing FSD are highly lacking.~The objectives of this proposed study are:~To describe and investigate the healthcare use and healthcare costs for individuals with FSD and compare them with~individuals without FSD, and~individuals with severe physical disease
The goal of this observational case-control study is to learn about direct healthcare use and costs of functional somatic disorders.~The aim of the proposed study is to investigate the use and costs of direct healthcare for individuals with functional somatic disorders.~Researchers will compare direct healthcare use and costs of individuals with functional somatic disorders and compare them with that of healthy controls and individuals with other severe physical disease, respectively.