“…Table 2 shows study populations, interventions, and extracted outcome measures for eligible trials. Seventeen studies used changes in xerostomia symptoms as an outcome; outcome measures included the visual analogue scale (nine studies) [17][18][19][20][21][22][23][24][25], the xerostomia inventory (one study) [26], the Walizer Mouth Dryness questionnaire (one study) [27], the global rating of change scale (two studies in one paper) [28], general xerostomia questionnaires (two studies) [29,30], and the xerostomia items of the European Organization for Research and Treatment of Cancer Quality of Life Head and Neck Module (EORTC-H&N35) instrument (two studies) [31,32]. At endpoint, symptoms were assessed shortly after administration of the intervention in three studies [28,29], and after 180 minutes in one trial [19], and therefore refer to symptoms perceived by participants during enhancement of salivary gland function.…”