No health maintenance organization plan, medical group/staff model, independent practice association or any other entity shall prohibit or restrict any provider from disclosing to any subscriber, enrollee or member any information that such provider deems appropriate regarding the nature of treatment, risks or alternatives thereto, the availability of other therapy, consultation or test, the decision of any plan to authorize or deny services, or the process that the plan or any person contracting with the plan uses or proposes to use, to authorize or deny health care services or benefits. Any such prohibition or restriction contained in a contract with a provider entered into after August 28, 1997, shall be void and unenforceable.