An Embodied Conversational Agent in an eHealth Self-management Intervention for Chronic Obstructive Pulmonary Disease...

Embodied conversational agents (ECAs) have the potential to stimulate actual use of eHealth apps. An ECA's design influences the user's perception during short interactions, but daily life evaluations of ECAs in health care are scarce.

This is an exploratory, long-term study on the design of ECAs for eHealth. The study investigates how patients perceive the design of the ECA over time with regard to the ECA's characteristics (friendliness, trustworthiness, involvement, expertise, and authority), small talk interaction, and likeliness of following the agent's advice.

We developed an ECA within an eHealth self-management intervention for patients with both chronic obstructive pulmonary disease (COPD) and chronic heart failure (CHF), which we offered for 4 months. Patients rated 5 agent characteristics and likeliness of following the agent's advice before use and after 3 and 9 weeks of use. The amount of patients' small talk interaction was assessed by log data. Lastly, individual semistructured interviews were used to triangulate results.

Eleven patients (7 male and 4 female) with COPD and CHF participated (median age 70 years). Patients' perceptions of the agent characteristics did not change over time (P>.05 for all characteristics) and only 1 participant finished all small talk dialogues. After 3 weeks of use, the patients were less likely to follow the agent's advice (P=.01). The agent's messages were perceived as nonpersonalized and the feedback as inappropriate, affecting the agent's perceived reliability.

This exploratory study provides first insights into ECA design for eHealth. The first impression of an ECA's design seems to remain during long-term use. To investigate future added value of ECAs in eHealth, perceived reliability should be improved by managing users' expectations of the ECA's capabilities and creating ECA designs fitting individual needs.

Netherlands Trial Register NL6480; https://www.trialregister.nl/trial/6480.