The phrase "are classed as either" is correct and usable in written English.
You can use it when categorizing items or concepts into distinct groups or classifications.
Example: "The animals in the zoo are classed as either mammals or reptiles based on their biological characteristics."
Alternatives: "are categorized as either" or "are divided into either".
Still, 91% of Bhutanese are classed as either narrowly, extensively or deeply happy.
Most conventional steam boilers are classed as either fire-tube or watertube types.
More and more of us are sleepwalking into this problem: more than a third of children are classed as either overweight or obese by the time they leave primary school.
Typically, one to two thinnings are undertaken during a rotation and depending on the size of felled trees these are classed as either pre-commercial or commercial thinnings.
These tissues are composed of cells with walls that are classed as either primary cell walls that prevent cell bursting and regulate cell expansion, or non-extendable secondary cell walls, restricted to certain cell types, which have mechanical properties resisting external forces that would lead to cell collapse.
The NDI categorisations used were: change in NDI score between 4 months and 12 months, change in Vernon category between 4 months and 12 months, 4 month Vernon categories, 12 month Vernon categories and finally a categorisation of patient outcome trajectories defined by Sterling et al., where neck injuries are classed as either mild, moderate or chronic-severe [ 30].
Although ciliar and flagellar locomotion are clearly forms of appendicular locomotion, pseudopodial locomotion can be classed as either axial or appendicular, depending upon the definition of the pseudopodium.
For English speakers, KAL Qs split-screen layout repositions the alphabet into two unequal blocks of letters, with consonants in the left block (plus Y which can be classed as either) and vowels plus the remaining consonants (including K, L and Q) in the right.
Within the VDAC1 PPI network, using Yu et al's [28] categorisation, encoded proteins were classed as either hubs (nodes with high degree values constituting vulnerable areas of the network) and/or bottlenecks (those with high betweenness centrality scores corresponding to key intersecting nodes).
Procedures were classed as either diagnostic or therapeutic.
