HB 1642 proposes to create an expedited credentialing process for chiropractors joining an established professional practice with a contract under a managed care plan. Under the bill, chiropractors who meet specific criteria—including holding a valid Texas chiropractic license and submitting required documentation—will be treated as participating providers for payment purposes while awaiting credentialing approval. The bill mandates that chiropractors be allowed to collect copayments and receive reimbursements from the managed care plan during this process. If the chiropractor is ultimately deemed ineligible after credentialing, the managed care issuer may recover payment differences, though patients will be held harmless and not responsible for out-of-network costs. The bill also limits managed care issuers' liability when complying with these provisions.