The review, which covered communications in the December 2012 and March 2013 half and full year results, resulted in the market watchdog contacting two issuers who didn't comply with the guidelines in the note, both of whom agreed to improve their future disclosure.
The FMA said it found instances where companies reconciled the non-standard measure back to the official result, but hadn't included it in the market communication, heightening the risk investors wouldn't cross-reference the changes.
"FMA expects a reconciliation to be provided in each and every document where non-GAAP measures are disclosed," the review said. "We also remind issuers that when disclosing non-GAAP profit measures this should be reconciled to GAAP profit being net profit after tax."
It also found instances where companies didn't explain how non-standard measures were used internally and why they are useful.
The FMA also questioned the use of adjusted earnings before interest, tax, depreciation and amortisation while still referring to the measure as EBITDA.
"Even where the EBITDA figure with its additional adjustments is explained and reconciled in the market communication, the use of an incorrect label can be misleading," the report said.