I researched, designed and implemented the multimodal interface for an AI-powered medical conversational agent

I researched, designed and implemented the multimodal interface for an AI-powered medical conversational agent

Group of two project · 2025 Apr - June

Role

UX Research, User flow Design, Prototype, Qualitative Evaluation

UX Research, User flow Design, Prototype, Qualitative Evaluation

Collaboration

Tool

Figma, Unity, C#, Llama, Vosk, Kokoro, AI-assisted development

Outcome

Experts found the agent credible for guiding the assessment, while highlighting turn-taking and response reliability as priorities for further development.

Background

Conducted with Tactus, an addiction healthcare organization in the Netherlands, this research project explored how an embodied conversational agent could complement existing care by making alcohol-withdrawal assessments more accessible and flexible for people with MBID.

Topic

Supporting CIWA-Ar assessments through chatbot
Supporting CIWA-Ar assessments through chatbot

The CIWA-Ar monitors ten alcohol-withdrawal symptoms and may require reassessment every one to four hours, creating a substantial clinical workload while posing accessibility challenges for people with MBID undergoing alcohol withdrawal.

How might an embodied chatbot support accessible, repeated assessments?

Approach

Research-informed design direction

With no direct access to patients during the early phase, we reviewed research on MBID accessibility, medical conversational agents, and alcohol-withdrawal assessment to establish the initial design direction.

Understanding the users

People with MBID benefit from simple, and structured interactions

People with mild to borderline intellectual disabilities (MBID) may experience limited attention, restricted vocabulary, memory difficulties, and difficulty distinguishing relevant from irrelevant information. Conventional assessments can therefore be challenging to follow. This calls for interactions that use short questions, concrete language, repetition, and immediate feedback.

Researching Medical ECAs

Medical ECAs can support users through multiple modalities, a clear role, and appropriate emotional support

We reviewed prior research on medical embodied conversational agents (ECAs) to understand how their communication and presentation may support comprehension, engagement, and trust. Three themes informed our initial design direction.

01 Multimodal guidance

Research insight

Speech, subtitles, and visual cues can reinforce comprehension.

Design implication

Present each question through both speech and on-screen text.

02 A clear clinical role

Research insight

Prior healthcare ECA studies often use a professional, middle-aged female character to communicate familiarity and care.

Design implication

Explore a professional healthcare character.

03 Motivational and empathetic communication

Research insight

Supportive and motivational language can help users feel heard, but excessive empathy may distract from the assessment or feel inappropriate.

Design response

Use brief, supportive responses while keeping the assessment focused.

Design Goal

Design a structured, multimodal conversational assessment
Conversation Guidelines
  • Use simple, concrete language

  • Ask one question at a time

  • Repeat or rephrase when needed

  • Provide immediate, clear feedback

  • Maintain a predictable conversational structure

Interface Guidelines
  • Present speech together with on-screen text

  • Provide clear, limited response options

  • Use a professional and approachable agent

  • Keep the interface visually simple

Rapid Prototyping

Translating research insights into a functional prototype

To test the concept early, we initially developed the conversational AI and interface as separate components. My teammate prototyped the Llama-based AI behavior, while I designed and implemented the screen-based interface in Unity.

01 AI behavior prototype
Developed by my teammate

My teammate translated our design guidelines into prompts and developed a Llama-based prototype to test the agent’s assessment flow and responses.

My teammate translated our design guidelines into prompts and developed a Llama-based prototype to test the agent’s assessment flow and responses.

02 Unity interface
Designed and implemented by me

I designed and implemented the Unity experience, including the embodied agent, visual question presentation, speech input, and spoken responses.

I designed and implemented the Unity experience, including the embodied agent, visual question presentation, speech input, and spoken responses.

03 Integrating the multimodal experience

I connected the interface with speech-to-text, the language model, and text-to-speech, turning the separate prototypes into a functional assessment flow for expert review.

▴Multimodal Prototype Architecture

Focus Group

Reviewing the prototype with clinical experts

We conducted an online focus group with five clinical detoxification experts, including nurses, e-health specialists, and a researcher. We used the initial prototype as a discussion probe to assess its fit with clinical practice and identify improvements to the agent’s communication and interaction design.

Feedback to AI behavior

AI responses felt overly empathetic for the clinical context

Experts felt that the agent’s tone was sometimes overly empathetic for the direct communication expected in Dutch clinical care.

Feedback on agent appearance

The agent’s visual style did not align with the clinical context

Experts valued the multimodal interaction but felt that the agent’s anime-inspired visual style did not align with the clinical context. They preferred a more realistic and professional-looking character.

Design response

We introduced clearer behavioral guidelines and limited empathy to brief, task-focused acknowledgements.

SPEECH OUTPUT

SPEECH OUTPUT

"I can see that you are feeling quite uncomfortable…"

"I can see that you are feeling quite uncomfortable…"

Before

→

SPEECH OUTPUT

SPEECH OUTPUT

"It’s okay if you’re unsure. Let’s move to the next question."

"It’s okay if you’re unsure. Let’s move to the next question."

After

Design response

I replaced the stylized avatar with a more neutral, professional healthcare character.

Before

→

After

Final Design

A guided, multimodal assessment designed for clarity

Final Design

A guided, multimodal assessment designed for clarity

Final Design

A guided, multimodal assessment designed for clarity

Design Features

  1. A predictable three-stage assessment flow

The assessment guides users through three clear stages, briefing, assessment, and completion. Each screen presents one task at a time to reduce cognitive load and make progress easier to follow

  1. Briefing

  • Introduce the assessment

  • Ask for the user’s name

  • Check whether they have questions

→

  1. Assessment

  • Present one question at a time

  • Clarify the question when needed

  • Confirm the user’s response

→

  1. Completion

  • Confirm that the assessment is complete

  • Explain what happens next

  1. Structured assessment with flexible conversational support

Design Features

To preserve the required CIWA-Ar questions and sequence, the interface controls the core assessment flow. The conversational AI supports this flow by clarifying questions, answering additional queries, and asking follow-up questions when needed, without changing or skipping required items.

Fixed assessment structure

Briefing → Question 1 → Question 2 → Question 3 → … → Completion

Flexible conversational support

Clarify questions · Answer additional queries · Ask follow-ups

  1. Clear about its AI identity and clinical role

To avoid misleading users, the agent clearly introduces itself as an AI system and explains how their responses will be used to support clinical care.

Design Features

SPEECH OUTPUT

“I am a computer-based assistant. My responses are generated by AI.”

“Your answers will help your care team support your treatment.”

“I am a computer-based assistant. My responses are generated by AI.”


“Your answers will help your care team support your treatment.”

▴Example of the agent’s spoken introduction

Qualitative Evaluation

Clinical expert evaluation of the prototype

Three clinical detoxification experts completed a full walkthrough of the prototype while I observed their interactions. Follow-up interviews were thematically analyzed to identify key usability and design insights.

3 clinical experts

≈15 min/session

Observation + interview

Results

The prototype felt credible and supported task completion, but unclear turn-taking and occasional context errors limited its reliability.

Credible guidance

The agent felt credible and appropriate for guiding the assessment.

Participants found its questions, clarifications, and guidance suitable for the assessment. Its human-like appearance, calm voice, and professional tone contributed to credibility, while its responses were generally clear and easy to follow.

Turn-taking uncertainty

Multimodal input created uncertainty about when and how to respond.

All participants completed the assessment, but initially hesitated over whether to speak or use the on-screen controls—and whether the agent was ready to listen.

Context errors

Occasional context errors weakened trust in the agent.

Most responses were clear and relevant, but the LLM occasionally misinterpreted user input and generated responses that did not fit the assessment context.

Future improvements

Based on the evaluation, we identified three priorities for future development.

  1. Clarify turn-taking and input options

Introduce clearer onboarding and explicit interaction states, including a dedicated button for asking questions and clearer indicators of when voice or on-screen input is available.

  1. Improve AI response reliability

Evaluate alternative language models and strengthen prompt constraints, context management, and fallback responses to reduce misinterpretations and off-topic answers.

  1. Evaluate with the target users

Test the prototype with people with MBID in a supervised setting to assess comprehension, usability, safety, and its ability to support assessment completion.

Retrospective

The project has taught me few important things.

It is important to be clear that AI-generated, it can be presented as the

Be clear for AI generated

Next

UX Internship at BenQ

Contributed to education software through research, and feature delivery

Next

UX Internship at BenQ

Contributed to education software through research, and feature delivery

☺ 2026 Jasmine Lin

Made with tea, music & love

☺ 2026 Jasmine Lin

Made with tea, music & love

☺ 2026 Jasmine Lin

Made with tea, music & love