Link between pharyngeal acid reflux episodes and the effectiveness of proton pump inhibitor therapy

Figure 2 Flow-chart of study population enrollment. Excessive pharyngeal acid reflux (PAR) is defined as PAR ≥ 2 episodes; Excessive distal esophageal acid reflux (EAR) a is defined as distal EAR total time ≥ 4.2% of 24-hour, or ≥ 6.3% of upright position, or ≥ 1.2% of supine position; Composite pH (+) is defined as PAR (+) and/or EAR (+); Both pH (+) is denoted as PAR (+) and EAR (+); Both pH (-) is denoted as non-reflux controls. PPI: Proton pump inhibitor.