Module 1: High version; Module 2: High version; Module 3: Low version

Module 1: High version; Module 2: High version; Module 3: High version

Basic module: aims to improve the participant's illness perceptions and standardize HF knowledge at the start of the intervention and doing exercises.- Low version Module 1: Symptom awareness exercises 2 times in 1 week, and written feedback HF nurse - Low version Module 2: Coaching in symptom management response and choose symptom response option to experiment with. Written feedback from HF nurse - High version Module 3: Instruction and doing symptom management experiments for 2 weeks + keep logs; Verbal feedback HF nurse

Basic module: aims to improve the participant's illness perceptions and standardize HF knowledge at the start of the intervention and doing exercises.- Low version Module 1: Symptom awareness exercises 2 times in 1 week, and written feedback HF nurse - High version Module 2: Coaching in symptom management response and choose symptom response option to experiment with. Verbal feedback from HF nurse - High version Module 3: Instruction and doing symptom management experiments for 2 weeks + keep logs; Verbal feedback HF nurse

Basic module: aims to improve the participant's illness perceptions and standardize HF knowledge at the start of the intervention and doing exercises.- Low version Module 1: Symptom awareness exercises 2 times in 1 week, and written feedback HF nurse - High version Module 2: Coaching in symptom management response and choose symptom response option to experiment with. Verbal feedback from HF nurse - Low version Module 3: Instruction and doing symptom management experiments for 2 weeks + keep logs; Written feedback HF nurse

Basic module: aims to improve the participant's illness perceptions and standardize HF knowledge at the start of the intervention and doing exercises.- High version Module 1: Symptom awareness exercises 6 times in 2 weeks, and verbal feedback HF nurse - Low version Module 2: Coaching in symptom management response and choose symptom response option to experiment with. Written feedback from HF nurse - Low version Module 3: Instruction and doing symptom management experiments for 2 weeks + keep logs; written feedback HF nurse

Basic module: aims to improve the participant's illness perceptions and standardize HF knowledge at the start of the intervention and doing exercises.- High version Module 1: Symptom awareness exercises 6 times in 2 weeks, and verbal feedback HF nurse - Low version Module 2: Coaching in symptom management response and choose symptom response option to experiment with. Written feedback from HF nurse - High version Module 3: Instruction and doing symptom management experiments for 2 weeks + keep logs; Verbal feedback HF nurse

Basic module: aims to improve the participant's illness perceptions and standardize HF knowledge at the start of the intervention and doing exercises.- High version Module 1: Symptom awareness exercises 6 times in 2 weeks, and verbal feedback HF nurse - High version Module 2: Coaching in symptom management response and choose symptom response option to experiment with. Verbal feedback from HF nurse - Low version Module 3: Instruction and doing symptom management experiments for 2 weeks + keep logs; Written feedback HF nurse

Basic module: aims to improve the participant's illness perceptions and standardize HF knowledge at the start of the intervention and doing exercises.- High version Module 1: Symptom awareness exercises 6 times in 2 weeks, and verbal feedback HF nurse - High version Module 2: Coaching in symptom management response and choose symptom response option to experiment with. Verbal feedback from HF nurse - High version Module 3: Instruction and doing symptom management experiments for 2 weeks + keep logs; Verbal feedback HF nurse

Using hospital data: number of HF-related ER and hospital admissions

Using hospital data: Length of stay in days

Using hospital data: Number of unscheduled (telephone) consultations with the HF outpatient clinic).

The 37-item Multidimensional Assessment of Interoceptive Awareness version 2 will be used to measure eight dimensions of interoception (noticing, not-distracting, not-worrying, attention regulation, emotional awareness, self-regulation, body listening, trust). Scale scores are 0-5, where higher scores indicate more interoceptive awareness.

The Illness Perception Questionnaire (revised) identity scale will be used to measure symptom attribution. Participants will be asked if they have experienced a number of symptoms since their illness, and if they feel the symptoms are related to their current illness. Response is by answering 'yes' or 'no' to each symptom. The number of yes-rated items are summed to give an overall score (range 0- 21). A high score represents strongly held beliefs about the number of symptoms attributed to HF.

Confidence will be measured using the 10-item Self Care Self-Efficacy Scale measuring self-care self-efficacy in chronic illness. The standardized score range from 0-100. Scores >70 indicate better self-care confidence.

Symptom management skills will be evaluated with 8-item Control Attitudes Scale-Revised. Range score is 8-40, higher scores indicate greater perceived control.

Treatment fidelity will be evaluated with the user logs of the platform of patient and nurse. Written feedback from HF nurses to patients in each module will be evaluated using self-assessments for the HF nurses. The number of minutes of the verbal feedback in each module will be registered by nurses.

Descriptive analysis of self-assessments made by patients in module 2.

Experiences of patients will be evaluated using semi-structured interviews. We aim to include 5 participants per version per module (total 40 participants). All participating HF nurses are asked to share their experiences with the research team at the end of the intervention.