Table 1.

Summary of the quality of evidence

Journal/Publication year	Type of study	Number of subjects	Reference
American Journal of Veterinary Research/1984	Prospective with control group, single center	298	[8]
The Canadian Veterinary Journal/1996	Prospective with no control group, multi-center	27 and 14 respectively	[9]
The Canadian Veterinary Journal/1997	Prospective with no control group, single center	120	[10]
Veterinary Parasitology/2000	Prospective, blind, randomized, with control group, multi-center	42	[11]
Veterinary Parasitology/2000	Prospective, blind, randomized, with control group, multi-center	207	[12]
Veterinary Parasitology/2000	Prospective no control group, single center	41	[13]
Parasitology Research/2005	Prospective, blind, randomized, with control group, multi-center	53	[14]
Australian Veterinary Journal/2006	Prospective, blind, randomized, with control group, single center	30	[15]
Veterinary Research Communications/2011	Prospective with control group, single center	22	[16]
Veterinary Parasitology/2016	(1) Laboratory study, blind, randomized, placebo, with control group, single center (2) Prospective, blind, randomized with control group, multi-center	(1) 44 and (2) 79 respectively	[17]
Parasite/2016	Prospective, randomized, with control group, single center	20	[18]
Veterinary Dermatology/2016	Prospective, no control group, single center	17	[4]
Parasites & Vectors/2016	Prospective, double-blind, randomized, with control group, single center	29	[19]
Parasite/2018	Prospective, double-blind, randomized, no control group, multi-center	80	[20]
Parasites & Vectors/2020	Prospective, single-blind, with control group, multi-center	135	[3]
The Canadian Journal of Veterinary Research/2020	Prospective, with control group, single center	142	[21]