Clarify End-dated HCPCS Codes G0431 and G0434

HCPCS G0431 and G0434 were end-dated effective December 31, 2015. The new HCPCS codes for drug screening are not reimbursed by NCTracks. When billing for drug screening for dates of service on and after January 1, 2016, providers should select the most appropriate CPT code from the lab section of the 2016 CPT manual.