Staggered by increasing health insurance costs, several large US companies met in 1998 to influence quality and affordability. The resulting Leapfrog Group agreed to base their purchase of health care on principles that "encourage provider quality improvement and consumer involvement". The group was officially launched in November 2000 with the initial focus provided by the 1999 Institute of Medicine report – reducing preventable medical mistakes (the report recommended that large employers leverage their purchasing power for the quality and safety of health care). The "leapfrog" concept involved large advances stimulated by rewarding hospitals that implement significant improvements (the Leapfrog Hospital Rewards Program). The quality practices mandated are computerized physician order entry (CPOE), evidence-based hospital referral, intensive care unit (ICU) staffing by physicians experienced in critical care medicine, and a "Leapfrog Safe Practices Score", based on the National Quality Forum endorsed Safe Practices. Additional initiatives now include public reporting of health care quality and outcomes (hospital quality ratings) to influence consumers' choices. Leapfrog now includes more than 170 large private and public healthcare purchasers providing health benefits to more than 37 million employees and retirees, funded by the Business Roundtable, the Robert Wood Johnson Foundation and Leapfrog members.