Objectives — To identify families in which the parents reported the child's illness as particularly stressful (high perception of illness threat), and to find out which health problems the parents perceive as particularly threatening.

Design — The parents registered the diagnosis and perception of illness threat in relation to the child's latest illness within a four-week retrospective period. Selected psychosocial conditions of the families were recorded in the same questionnaire. Setting - 18,949 families with at least one child under the age of 8 years, resident in the County of Ringkobing in western Denmark at 1 March 1988.

Subjects — An age-stratified random sample of 1982 families was entered in the study. 85% of the families returned the questionnaire.

Results — There was a considerable variation in the parents' perception of illness threat. On the basis of a score it was possible to group parents with a high, medium, and low perception of illness threat. Every fourth family reported a high perception of illness threat. A multivariate analysis, with a high perception of illness threat as dependent and selected psychosocial conditions and the diagnosis as independent variables, led to the following main results: 1) parents with a high perception of the general health threat («worried» parents) most frequently reported a high perception of illness threat, 2) the diagnoses were decisive; in particular, inflammation in the middle ear, bronchitis, pneumonia, and accidents led to the parents' reporting a high perception of illness threat, 3) parents without experience of children and children's illnesses more frequently perceived an actual illness as a high illness threat than parents with this experience, 4) parents more frequently perceive an illness in girls as a high illness threat.

Conclusions — «Worried» parents, without experience of children and children's illnesses, perceive the child's latest illness as a high illness threat. These families need special care.