Mmm think about this differently..
As with NOA, what you want here is to differentiate the accruals from the actual cashflow.. so you eliminate the Operating Cashflow from the Net Income (in order to get the accruals).. next, if you want to compare a company A that uses IFRS vs company B that uses US. GAAP, remember that in one you can report interest expense as CFO and in other as CFI or CFO.. in order to mitigate this issue when calculating the NOA from the cashflow statement you just eliminate CFI also.. so NI - CFO - CFI will give you the accruals and will be more easily comparable with IFRS vs GAAP..
Regards from Mexico,
Jorge