An independent financial statement audit done by external auditors is the most extensive attest service provided by auditors, and it is still limited. A review of financial statements by an independent auditor is even more limited in scope.
Reviews amount to auditors looking at account balances and determining whether or not the balances look reasonable. They will perform some analytical procedures on the financial statements to further analyze the numbers. On occasion, they may ask to see some details about accounts and their balances, but this happens on a very limited basis.