Table 2.

Self-reported knowledge about contaminated nutritional supplements (NSs) and dietary supplement third-party testing (% and N) for the total group, professionals working or not working with Olympic athletes, and sports dietitians vs. other professions.

			Working with Olympic Athletes			Profession
Questions		Total	Yes	No	p-Value	Sports Dietitian	Other Profession	p-Value
No. (type of scale)		% (N)	% (N)	% (N)		% (N)	% (N)
Knowledge
1 (L)	Contaminated NSs have no small effect or positive effect at all.	35 (111)	41 (59)	39 (52)	0.033	36 (26)	25 (85)	0.005
2 (L)	Use of contaminated NSs can lead to a positive doping test.	68 (216)	81 (116)	57 (100)	<0.001	88 (52)	63 (164)	0.003
3 (Y/N)	Are you familiar with NSs of which ingredients are listed on the WADA doping list?	44 (141)	55 (79)	35 (62)	<0.001	66 (39)	39 (102)	<0.001
4 (Y/N)	Are you familiar with the NZVT system?	47 (151)	69 (99)	30 (52)	<0.001	88 (52)	38 (99)	<0.001
5 (Y/N)	Products listed on the NZVT list are not tested on efficacy. *	61 (89)	67 (66)	47 (23)	0.017	78 (40)	51 (49)	0.007
6 (Y/N)	Only products with the NZVT logo on the label are always tested. *	53 (78)	44 (43)	47 (23)	0.295	61 (31)	49 (47)	0.106
7 (Y/N)	The absence of the NZVT logo on the label indicates that only certain batches of the NSs are tested. *	43 (63)	46 (45)	37 (18)	0.290	59 (30)	34 (33)	0.155
8 (Y/N)	The NZVT system does provide a 99% guarantee that tested NSs are free from doping substances. *	72 (106)	74 (72)	69 (34)	0.604	88 (45)	64 (61)	0.111

Significant differences are indicated in bold. Questions 1–4 are based on the total population (n = 601, with n = 80–85 missing answers). Questions 5–8 were answered by 259 of those that answered Y (n = 370) on question 4, which asked if they were familiar with the NZVT system. L = Likert scale; Y/N = Yes/No. Asterisks indicate that results are based on questions that were asked only when participants answered to be familiar with the NZVT system (N = 147). Significant differences are expressed in bold font.