progression.vfi {vfprogression}

progression according to VFI (significant slope, p<=0.05)

Description

progression.vfi returns the progression criterion used in Aptel et al. (2015).

Usage

progression.vfi(measmatrix)

Arguments

measmatrix

is a data frame. MUST contain the following columns: 'vfi' (visual field index), 'yearsfollowed', and 'eyeid'. Rows represent the single measurements. The minimum measurements (rows) is 3.

Value

"stable", "worsening", or "improving" of measurements in timepoints

See Also

https://www.ncbi.nlm.nih.gov/pubmed/26095771/

Examples

data(vf.vfi)
colnames(vf.vfi)
progression.vfi(vf.vfi)
progression.vfi(vf.vfi[vf.vfi$eyeid == 1,])
progression.vfi(vf.vfi[vf.vfi$eyeid == 2,])