Every year, hundreds of people are diagnosed with Chronic Lymphocytic Leukaemia (CLL), a type of blood cancer, in the Netherlands. While many treatments exist, the medical guidelines are incredibly complex, making it difficult for patients to understand which option best fits their unique life and genetic profile. This case study illustrates how CMyLife used the Patients Know Best (PKB) platform and its flexible APIs to launch a digital "Decision Aid". By integrating a patient’s own health record with medical guidelines, the tool empowers patients to take control of their care, ensuring that treatment choices are made with them, not just for them.

Choosing a cancer treatment is one of the most stressful experiences a person can face. For CLL patients, information is often fragmented and overly technical. Patients frequently feel like passive observers in their own care because they don’t have a clear way to compare how different treatments (like daily pills versus hospital-based chemotherapy) will impact their daily lives or align with their specific DNA mutations. Without a structured way to prepare, hospital consultations can feel rushed, leaving patients feeling uncertain about their path forward.

CMyLife developed a free online CLL Decision Aid that integrates directly with the Patients Know Best platform.

Data-driven personalisation: Using PKB’s APIs, the tool securely accesses a patient’s medical data, including specific DNA mutations like IGHV or TP53, which are critical for determining treatment effectiveness.

• Patient-first input: Patients answer a series of questions about their personal life, such as their ability to travel to the hospital and their caregiving responsibilities.
• Preference matching: Patients rank what matters most to them, such as minimising side effects (ranked #1, with votes of 25% of users) or maximising the time until the disease returns (ranked #2 with votes of 20% of users).
• The "shared decision" summary: The app generates a clear, personalised summary of treatment options that patients can take into their doctor’s appointment to lead a more informed discussion.

Since launching in September 2023, the CLL Decision Aid has demonstrated that when patients are given the right digital tools, they move from being passive recipients of care to active partners in their treatment journey. Across 46 hospitals in the Netherlands, the impact of the Patients Know Best integration has been significant:

• Broad adoption: Patients  across 46 different hospitals in the Netherlands have actively used the CLL Decision Aid, representing over 10% of yearly diagnosed CLL patients in the Netherlands, who are moving towards making their first treatment decision.
• Improved patient insight: 39% of users reported that the tool gave them a much better understanding of their treatment options.
• Confidence in care: 70% of patients found the information clear and informative, with some respondents stating that it supported their conversation with their doctor.
• Clinical efficiency: Haematologists noted that the tool allowed patients to arrive well-informed, leading to calmer, more productive consultations where the patient felt confident in the final choice. By capturing the "basics" and personal preferences via PKB beforehand, consultations shifted from repetitive information-giving to calm, high-level, shared decision-making.

The CLL Decision Aid is expected to become a central tool for long term or chronic disease management. It will be expended in the near future with the following features: 

• Expanding the reach: Due to high demand, CMyLife plans to develop "Second-line" decision aids for patients whose cancer has returned after initial treatment.
• Real-time monitoring: A new project, cmyVitaLog, is being integrated to allow patients to track side effects digitally after treatment begins, providing even more data for future decision-making.

In 2026, CMyLife is launching version 2 of the app.