Fig. 4.

Distribution as per type of data sources. Data sources mapped in this review are categorized broadly into 6 different categories, comprising observational studies, registries, surveys, administrative databases, claims databases, and others. Observational studies include cohort studies, cross-sectional studies, prospective studies, retrospective studies, longitudinal studies, and population-based studies, as defined by the authors of the individual publications. HF, heart failure; ACS, acute coronary syndrome; AF, atrial fibrillation.