Table 3.

Summary of existing unsupervised learning performance in terms of accuracy in the healthcare industry.

Common Hard Clustering Algorithms	Reference	Year	Task	Accuracy
K-means	[71]	2021	Heart disease prediction	88%
K-medoids	[72]	2021	Anomaly detection in smart healthcare	75.89%
Hierarchical clustering	[74]	2018	Mental health prediction	90%
Some Common Soft Clustering Algorithms	Reference	Year	Task	Accuracy
Fuzzy c-means	[75]	2019	Analysis of patient satisfaction perception	76%
Gaussian Mixture Model	[81]	2021	Anomaly Detection	95.5%
Hidden Markov Model	[82]	2020	Healthcare audio event classification	70%