Strengths and limitations
RECRUITMENT
Despite this being a small study, a strength is that it follows guidelines for health economic evaluations in digital health. We translated the clinical outcome to a value for patients and then valued the resources needed to provide the treatmentA limitation of the present study concerns the differences between groups regarding baseline characteristics, distribution among different sites, and differences in available resources at the recruitment sites. It is still unclear if need of healthcare was affected by differences between groups regarding care-seeking behavior at baseline, treatment approaches at the different clinics, or the fact that participants in the intervention group were encouraged to continue practicing the exercises on their own after the intervention period.Another limitation regards the costs for development of the internet-based treatment program and server. These costs were not included as part of the costs for treatment as we aimed to evaluate the clinical value in relation to costs, i.e., the costs for treatment if the internet-based treatment was implemented in clinical practice as a complement to usual care. Moreover, the infra-structure was already in place when the intervention was delivered as part of the regular Swedish digital healthcare system. However, infra-structures within healthcare systems may vary in different countries, as do of course other parameters, such as costs for healthcare personal. This can result in difficulties in generalizing our results to different geographical contexts, especially regarding cost-effectiveness of the intervention.It is worth to note that the visits to the clinic may cost more than what was stated in this study as only flexible costs were considered but not premises and operating costs. If so, the clinical costs were underestimated in this study.