Evaluating a Digital Aid to Improve ICD Decisions

Scale Title: PKKT-13 (13-Item Patient Knowledge Assessment)

Outcome Measure: Patient Knowledge of Heart Failure and Implantable Cardioverter-Defibrillators (ICDs)

Description: The PKKT-13 assesses participants' knowledge of heart failure, sudden cardiac death, ICD benefits and risks, and shared decision-making. The questionnaire consists of 13 true/false/don't know questions.

Scoring: Each correct response receives 1 point; incorrect and "Don't Know" responses receive 0 points. Total scores range from 0 (minimum) to 13 (maximum).

Score Interpretation: Higher scores indicate greater patient knowledge and therefore a better outcome.

Outcome Measure Title: Decision Regret Scale (DRS)

Outcome Measure Description: The Decision Regret Scale (DRS) is a 5-item questionnaire that measures participants' regret regarding their decision to receive or decline an implantable cardioverter-defibrillator (ICD). Each item is rated on a 5-point Likert scale, ranging from strongly agree to strongly disagree. Responses are scored and transformed to a total score ranging from 0 (minimum) to 100 (maximum). Higher scores indicate greater decision regret and therefore a worse outcome. A score of 0 indicates no regret, while a score of 100 indicates the highest level of regret.

Outcome Measure Title: Preparation for Decision Making Scale (PDMS)

Outcome Measure Description: The Preparation for Decision Making Scale (PDMS) is a 10-item questionnaire that measures how well educational materials and the decision-making process prepare participants to make an informed decision about receiving an implantable cardioverter-defibrillator (ICD). Each item is rated on a 5-point scale ranging from "Not at all" to "A great deal." The total score is calculated as the mean of the item scores, rescaled to a range of 0 (minimum) to 100 (maximum). Higher scores indicate greater preparation for decision-making and therefore a better outcome.

Weekly physical activity is assessed using the International Physical Activity Questionnaire for the Elderly (IPAQ-E) Short Form. Participants report the frequency (days per week) and duration (hours and minutes per day) of walking, moderate-intensity physical activity, and vigorous-intensity physical activity during the previous 7 days. Daily sitting time is also recorded. Physical activity is measured in minutes per week, calculated by multiplying the number of days by the average duration of each activity.

For each activity category, the minimum is 0 minutes per week. The questionnaire does not specify a maximum duration or total activity score. Higher values indicate greater physical activity, generally representing a better outcome, while higher sitting time indicates greater sedentary behavior, generally representing a worse outcome.

Clinician satisfaction with the implantable cardioverter-defibrillator (ICD) decision-making visit is assessed using a clinician-completed questionnaire. Satisfaction with the patient discussion is measured using a 5-point Likert scale ranging from 1 (Very dissatisfied) to 5 (Very satisfied). The minimum score is 1 and the maximum score is 5. Higher scores indicate greater clinician satisfaction and therefore a better outcome.

Patient satisfaction with the implantable cardioverter-defibrillator (ICD) decision-making process is assessed using a patient-reported questionnaire. The questionnaire evaluates satisfaction with the decision-making tool, worksheet, physician discussion, quality of information received, and preparation for the visit. Satisfaction items are measured using a 5-point Likert scale ranging from 1 (Very dissatisfied) to 5 (Very satisfied). The minimum score is 1 and the maximum score is 5 for each item. Higher scores indicate greater patient satisfaction and therefore a better outcome.

The Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) is a 36-item patient-reported questionnaire that assesses health-related quality of life across eight domains: physical functioning, role limitations due to physical health, bodily pain, general health perceptions, vitality, social functioning, role limitations due to emotional problems, and mental health.

Each of the eight domains is scored on a scale ranging from 0 (minimum) to 100 (maximum). Higher scores indicate better health-related quality of life and therefore a better outcome, while lower scores indicate poorer health-related quality of life and therefore a worse outcome.

The Kansas City Cardiomyopathy Questionnaire-12 (KCCQ-12) is a 12-item patient-reported questionnaire that assesses heart failure-related health status and quality of life. It evaluates four domains: physical limitations, symptom frequency, quality of life, and social limitations over the previous two weeks.

Responses are scored and transformed to a scale ranging from 0 (minimum) to 100 (maximum). Higher scores indicate better heart failure-related health status, fewer symptoms, fewer physical and social limitations, and better quality of life, representing a better outcome. Lower scores indicate worse heart failure-related health status and greater limitations, representing a worse outcome.

The Illness Intrusiveness Ratings Scale (IIRS) is a 13-item patient-reported questionnaire that assesses the extent to which illness and its treatment interfere with daily life and activities. The instrument evaluates three domains: Relationships and Personal Development, Intimacy, and Instrumental Activities.

Each item is rated on a 7-point scale ranging from 1 (Not very much) to 7 (Very much). The total score ranges from 13 (minimum) to 91 (maximum). Higher scores indicate greater illness-related interference with daily life and therefore a worse outcome, while lower scores indicate less interference and a better outcome.

Responses marked "Not applicable" are treated as missing, and total and subscale scores are prorated based on answered items.