Internet-Delivered Psychological Treatment for Parents With Health Anxiety by Proxy: Replicated Randomized Single-Case Experimental Design.

Background: Health anxiety by proxy is characterized by ruminations about severe illness in one's child that can cause severe distress in affected parents. Health anxiety by proxy may lead to repeated unnecessary medical consultations and checking the child's body for symptoms, as well as heightened attention to their child's behavior, sign of illness, and bodily symptoms. It has been hypothesized that health anxiety by proxy may pose a risk for transmission of maladaptive symptom coping and health anxiety from the parent to their child. In spite of this, no targeted treatment has previously been evaluated. Therefore, we developed an internet-delivered psychological treatment containing 8 modules based on cognitive behavioral therapy and acceptance and commitment therapy. Objective: The objective of this study was to investigate the feasibility and effect of the internet-delivered treatment PROXY for parents with health anxiety by proxy. Methods: A total of 4 participants with health anxiety by proxy entered a replicated randomized single-case experimental design. They were randomly allocated to a baseline period of 7-26 days before entering the 8-week treatment and 14-33 days follow-up phase. The primary outcomes were daily measures of anxiety, impact of anxiety, and value-based actions measured using 5 questions answered on a scale of 1-10 through a text-message link. The primary outcomes were analyzed using visual analysis and supplemented with statistical randomization tests. Secondary outcomes were standardized questionnaire measures of anxiety-related symptoms, experience of the treatment, and negative effects of the treatment reported using descriptive statistics for each participant individually. Results: Visual and statistical analyses indicated that PROXY was an effective treatment for 2 participants as the primary outcomes changed in the preferable direction for both of them. The effect of PROXY was questionable for the remaining 2 participants, although visual analysis showed that the impact of anxiety decreased for one of them. The 2 participants with questionable effect also thought that the treatment was too short. All 4 participants were happy with the treatment, but 2 participants experienced that health anxiety for their own health deteriorated during treatment. Conclusions: PROXY holds potential as a treatment for HA by proxy. However, more work is required to determine when and how PROXY should be introduced to parents with HA by proxy, particularly in relation to duration of treatment, possible comorbidities, and the need for findings to be replicated in larger groups.