Table 1.

Characteristics of the six studies included in the systematic review

Study, year	Country	Population and setting	Number of participants contacted	Response rate	Final number of participants	Data collection period	Characteristics of participants
Schaper et al., 201833	Germany	German laypeople from Göttingen, Berlin, Frankfurt, Cologne	NR	NR	43 (7 focus groups)	June 2016–November 2016	Age:18–25 (21%), 26–35 (32%), 36–50 (12%) 51–70 (26%), 70+ (9%)
							Sex: female (61%), male (39%)
							Education: 9 years (5%), 10 years (9%); high school (26%); vocational school (9%); academic degree (51%)
							Average time spent online per day in hours:
							0–1 (16%), 1–2 (37%), 2–4 (26%), 4–6 (7%)
							6+ (12%), none (2%)
Giraldi et al., 201628	Italy	Students enrolled in the Faculty of Medicine at the Università Cattolica del Sacro Cuore, Rome	380	0.471	179	2014	Age: median = 21 years
							Sex: female (59.8%), male (39.7%)
							Academic year: I (45.3%), II (17.9%), III (17.9%), IV (11.7%), V (6.7%)
Mählmann et al., 201630	Switzerland	Older adults attending Seniors’ University, Zurich	800	0.19	151	November 2013–March 2014	Age: mean = 76 years (SD = 6.05)
							Sex: female (45.7%), male (54.3%)
							Education: secondary school (4.6%); vocational education (44.4%); high school (18.5%); university degree (32.5%)
							Internet use: yes (92.1%), no (7.9%)
							Disease in family: yes (31.8%), no (65.65%)
Oliveri et al., 201629	Italy	Subjects with at least bachelor degree from the University of Milan, Milan	250	0.58	145	September 2015–January 2016	Age: mean = 31.41 (SD = 7.58)
							Sex: female (77.9%), male (22.1%)
							Education: 49% had a bachelor’s degree, 51% ranged from master degree to PhD and/or specialization
Stewart et al., 201832	The Netherlands	Online panel members, representative of the Dutch adult	1693	63%	836	June 2017	Age: 18–39 (29.9%), 40–59 (35.8%), 60+ (34.3%)
							Sex: male (50.5%), female (49.5%)
							Education level: low (32.5%); middle (43.3%), high (24.2%)
Mavroidopoulou et al., 201531	Greece	Undergraduate, postgraduate, doctoral students from various disciplines and university sites	NR	NR	725	January 2014–July 2014	Age: 71.9% was ≤25, 20.1% was 26–30, 85% were >30 years
							Sex: female (68.1%), male (31.9%)
							Education level: undergraduate (81.4%); postgraduate (14.2%); doctoral (4.4%)
							Study field: healthcare/biomedical (45.3%); non-biomedical sciences (54.7%)