Quest Diagnostics (DGX) has been gaining from its existing solid customer relationships, new customer wins, broad health plan access and advanced diagnostics offerings. The stock carries a Zacks Rank #2 (Buy) currently. Factors Driving DGX Stock Quest Diagnostics has been experiencing robust volume growth in its core business (excluding COVID testing), banking on the growth of new physician and hospital customers, a more favorable test mix with increased use of advanced diagnostics, continued strength in he ...