Fig 1.
Flow diagram summarizing the selection of eligible studies.
Table 1.
Basic characteristics of the included studies.
Fig 2.
Quality assessment of the included studies based on the JBI checklist.
Fig 3.
The pooled prevalence of olfactory among patients with MS.
Fig 4.
The funnel plot showing no evidence of publication bias, statistically supported by Egger’s regression test.
Table 2.
Subgroup analysis of pooled prevalence of olfactory.
Fig 5.
Studies reporting TDI, threshold, discrimination, and identification.
Table 3.
Level of heterogeneity and publication bias amongst the included studies.