Understanding Patterns of Fatigue in Health and Disease

Inclusion Criteria: * For all groups, participants will be included if they are willing to participate in intermittent ecological momentary assessments of fatigue, to wear an ECG patch, to provide questionnaire responses at baseline, and the end of the study, and to participate in an end of study interview. Inclusion Criteria for Group A, individuals with myeloma * A confirmed diagnosis of myeloma * Has experienced fatigue that is perceived by the participant to be worse than "normal tiredness" and that they associate with myeloma or treatment for myeloma Inclusion Criteria for Group B, heart failure * A formal diagnosis of heart failure * All stages of heart failure and all aetiologies and with no specific ejection fraction cut-off * Has experienced fatigue that is perceived by the participant to be worse than "normal tiredness" and that they associate with their cardiac disease or its treatment Inclusion Criteria for Group C, long COVID * Experiencing fatigue that is perceived by the participant to be worse than "normal tiredness", with or without other physical or psychological symptoms that developed during or after an infection consistent with COVID-19 * The fatigue (plus or minus any other symptoms) has continued for greater or equal to 12 weeks, and is not explained by an alternative diagnosis Inclusion criteria for Group D, control group • Individuals aged 18 years or over without the disease conditions specified in Groups A to C Exclusion Criteria: * Exclu…