Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of medical diagnostic product maker Alere (NYSE: ALR) jumped 10% today following a positive earnings report.

So what: Fourth-quarter revenue increased 12.5% to $651.1 million, topping estimates of $632.1 million. Earnings per share were also strong, coming in at $0.74, $0.03 better than analyst estimates.

Now what: The company did take a $383.6 million impairment charge in the quarter, leading to a $365 million GAAP loss. But estimates are usually compared to non-GAAP numbers that disregard one-time charges. Beating estimates is always good, but I would like to see results that don't include major write-offs, which added up to $1 billion in 2011.

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