TABLE 7.

Factors Affecting the Methodological Quality of Controlled Studies of Testosterone Supplementation

Authors, Year	Participants Lost to Follow-Up	Months of Follow-Up	Morning Blood Sampling	Participants Free of Other Treatments That Could Profoundly Affect Testosterone Levels	Randomized Participant Groups	Double-Blinded Study	For-Profit Funding Source
Vaughan et al, 2007	23/69 (33%)	36	Yes	Yes	Yes	Yes	No
Lu et al, 2006	9/47 (19%)	24	No	Yes	Yes	Yes	Partial
Sih et al, 1997	10/32 (31%)	12	No	No	Yes	Yes	No
Cherrier et al, 2003	0/12 (0%)	6	Yes	Yes	Yes	Yes	Partial
Tan and Pu, 2003	Not reported	12	No	No	Yes	Not reported	No
Kenny et al, 2002	23/67 (33%)	12	No	Yes	Yes	Not reported	No
Cherrier et al, 2005	3/32 (9%)	3	No	Yes	Yes	Yes	No
Kenny et al, 2004	0/11 (0%)	2.5	Yes	No	Yes	Yes	No
Fukai et al, 2010	Not reported	6	Yes	No	No	Not reported	No