Table 5.

Classification of Concerned Topics regarding PSO's Technique.

Theme/variants of PSO	Standard PSO	PSO with neural network	Improved/extended PSO	Hybridized PSO
Heart disease	[9, 16, 24, 25, 30, 32, 33, 37, 39, 42, 43, 57]	[14, 28]	[50, 51, 53, 54]	[46, 48]
Dental disease	[26]	—	—	—
Lymphatic disease	[8]	—	[55]	—
Celiac disease	[27]	—	—	—
Liver disease	[2, 24, 29, 34]	—	[51, 52, 55]	—
Cancer disease	[2, 24, 30–32, 34]	—	[15, 51, 53, 55, 56]	—
Brain disease	[24, 34–36, 38, 41, 44, 45]	—	[11, 13, 51, 55]	[47]
Hepatitis disease	[30, 40]	—	[51, 56]	—
Diabetes	[24, 30]	—	[49, 51, 53, 55, 56]	—
Others	—	[12]	[53]	—