From Investopedia:
Common Clues Of Financial Statement Manipulation:
"One of the most prevalent approaches to corporate accounting is to omit the bad and exaggerate the good. There are a number of subjective figures in any financial report that accountants can tweak. For example, a company may choose to exclude costs unrelated to its core operations when figuring its operating cash basis - say an acquisition of another company or purchasing investments - but will still include the revenue from the unrelated ventures when calculating their quarterly earnings. Fortunately, companies have to break down the figures, thus dispersing the smoke and mirrors, but if you don't look beyond a few main figures in a company's financials you won't catch it."