case_images: PMC4219705_01
case_images: PMC4219705_02
case_images: Proportion of incident atrial fibrillation cases identified in each source by age at diagnosis.
case_images: pone.0110900.g004.jpg
case_images: PMC4219705_02_pone.0110900.g004.jpg
case_images: pone-0110900-g004
case_images: The proportion of cases contributed by each source differed by age at diagnosis; individuals identified by inferred diagnosis criteria made up a greater proportion of cases diagnosed at younger ages (<=60 years), while cases diagnosed at older ages (>=80 years) were mostly identified from secondary care data (see  Figure 4 ).