Table 2.

Identified CTC clusters for vaccine (V)

CTC cluster ID	Noun phrases	Rank scores
V1	“acceptance rate”, “vaccine coverage”, “study vaccine”, “vaccine”, “rate vaccine”, “low vaccine”, “high vaccine”	12,960
V2	“antibody”, “nucleic acid”, “positive igm”, “nucleic acid test”, “igg antibody”, “detection rate”, “antibody detection”, “positive igg”	10,520
V3	“effect vaccine”, “associated vaccination”, “potential effect”, “effect vaccination”, “adverse effect”	2,522
V4	“high risk group”, “chronic disease”, “patient chronic”, “high risk”, “risk groups”	2,509
V5	“beta delta”, “variant infection”, “delta variant”, “variant”, “different variant”, “delta”, “delta variants”	2,193