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 WuXi PharmaTech (UNKNOWN:WX.DL) have fallen more than 14% lower today after dropping by as much as 18% in early trading. The Chinese-based medical research company reported disappointing earnings and provided weak guidance after yesterday's closing bell.

So what: WuXi's first quarter produced $146.7 million in revenue, which was up 11% year over year and slightly ahead of the $145.4 million Wall Street consensus. However, earnings of $0.30 per share fell $0.09 short of what analysts want, and both top- and bottom-line guidance for the second quarter and the whole year now come in below Wall Street's expectations.

WuXi's second-quarter guidance expects revenue to range from $160 million to $162 million, with EPS in the $0.46 to $0.48 range. Wall Street had been seeking $164.5 million in revenue and $0.49 in EPS. WuXi's full-year guidance calls for revenue in the $660 million to $670 million range, with EPS in the $1.80 to $1.85 range. Wall Street had expected $670.7 million in revenue and $1.95 in EPS. WuXi's EPS guidance anticipates losses of $0.20 per share in foreign exchange forward contracts.

Now what: WuXi's EPS guidance still looks to top its 2013 EPS by about 14%, and revenue is expected to grow by roughly 39%. This divergence between top and bottom lines might worry investors somewhat, but a more reasonable assessment of this situation would simply highlight the divergence between WuXi's EPS and its share price over the past year. Over the past five years, WuXi's share price has grown nearly twice as much as its EPS, and the correction that began in early 2014 could simply be a return to trend. There may be a good bargain here, but with WuXi's P/E ratio still near multiyear highs, it's tough to say so right now. I'd watch cautiously for a better opportunity, which may arrive before too long.

Alex Planes has no position in any stocks mentioned, and neither does The Motley Fool. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.