![I am using this data set of 20 patients to determine a cuttpoint for one of these miRNAs (e.g. miR-21) as diagnostic marker for ATB condition. I used the following function within cutpointr package:

opt_cut <- cutpointr(ATB, miR-21, Condition)

it returns an error:

<error/rlang_error> Can't convert a call to a string Backtrace:

1. cutpointr::cutpointr(ATB, miR - 21, Condition)
2. cutpointr:::cutpointr.default(ATB, miR - 21, Condition)
3. rlang::as_name(rlang::enquo(x))
4. rlang::as_string(x)
5. rlang:::abort_coercion(x, "a string")

Any help, highly appreciated.

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