Dry mouth in patients with a life-limiting condition or frailty: a study protocol for two intervention studies and a nested qualitative sub-study (the Dry mOuth Project, DROP)

Table 2 Data collection schedule and measurement instruments

Data collection	Measurement instrument	Visit 1 Week 0	Visit 2 Week 2	Visit 3 Week 4	Visit 4 Week 8	Visit 5 Week 12
Baseline characteristics	Questionnaire on patient characteristics	X
Dry mouth severity	Numeric Rating Scale (NRS) (11-point; from 0 to 10) [1, 31]	X	X	X	X	X
Dry mouth impact	Summated Xerostomia Inventory, shortened Dutch version (sXI-D, adapted) [32]	X	X	X	X	X
Oral health-related quality of life	Geriatric Oral Health Assessment Index, Dutch version (GOHAI-NL) [33]	X	X	X	X	X
Health-related quality of life	EuroQol 5 Dimensions 5 Levels (EQ-5D-5L) [34]	X		X	X	X
Functional status	Patient-reported functional status (PRFS) [35]	X	X	X	X	X
Patient-perceived effect	Global Perceived Effect, 7-point scale [36, 37]		X	X	X	X
Patient-reported medical costs	The Institute for Medial Technology Assessment (iMTA) Medical Consumption questionnaire (iMCQ, adapted) [38]	X		X	X	X
Medication changes	Changes in medication since the last visit		X	X	X	X
Adherence^a	Short questionnaire on adherence		X	X	X	X
Side-effects^a	Short questionnaire on side-effects		X	X	X	X

ISSN: 1472-684X