LabCorp LH shares ended the last trading session 3.7% higher at $226.22. The jump came on an impressive volume with a higher-than-average number of shares changing hands in the session. This compares to the stock's 11.5% loss over the past four weeks.LabCorp recorded a strong price increase on investors’ optimism surrounding the receipt of FDA emergency use authorization (EUA) for its VirSeq SARS-CoV-2 NGS (next-generation sequencing) Test on the PacBio Sequel II sequencing system. The VirSeq SARS-CoV-2 NGS Test is the first test to be approved for identifying and distinguishing between SARS-CoV-2 Phylogenetic Assignment of Named Global Outbreak (PANGO) lineages. It can detect specific SARS-CoV-2 strains to help health care providers make appropriate treatment decisions for patients based on their medical history and other diagnostic information.This medical laboratory operator is expected to post quarterly earnings of $4.66 per share in its upcoming report, which represents a year-over-year change of -24%. Revenues are expected to be $3.79 billion, down 1.3% from the year-ago quarter.While earnings and revenue growth expectations are important in evaluating the potential strength in a stock, empirical research shows a strong correlation between trends in earnings estimate revisions and near-term stock price movements.For LabCorp, the consensus EPS estimate for the quarter has been revised 3.4% lower over the last 30 days to the current level. And a negative trend in earnings estimate revisions doesn't usually translate into price appreciation. So, make sure to keep an eye on LH going forward to see if this recent jump can turn into more strength down the road.The stock currently carries a Zacks Rank #3 (Hold). You can see the complete list of today's Zacks Rank #1 (Strong Buy) stocks here >>>>LabCorp is a member of the Zacks Medical - Dental Supplies industry. One other stock in the same industry, AmerisourceBergen ABC, finished the last trading session 0.2% lower at $140.68. ABC has returned -5.6% over the past month.AmerisourceBergen's consensus EPS estimate for the upcoming report has changed -0.9% over the past month to $2.57. Compared to the company's year-ago EPS, this represents a change of +19%. AmerisourceBergen currently boasts a Zacks Rank of #3 (Hold).Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Laboratory Corporation of America Holdings (LH): Free Stock Analysis Report AmerisourceBergen Corporation (ABC): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research