Blue Cross and Blue Shield of Massachusetts and Boston-based Caritas Christi Health Care, a chain of six community hospitals in eastern Massachusetts, announced they have signed a new five-year "alternative quality contract." The contract includes a global payment system in which hospitals will be paid fixed amounts based on the estimated annual costs of patients' care instead of the fee-for-service system in which providers bill insurers for individual visits and procedures. It also includes incentives to improve the quality and affordability of care.