- Inappropriate laboratory ordering is a problem affecting medical systems worldwide. An intervention was called for as a result of increasing laboratory costs. Thus, we aimed to assess the impact of introducing computerized laboratory routines to a computerized primary care setting. The study included 380 primary care physician practices of Clalit Health Service (HMO) southern district (CHS-SD) in Israel, caring for 470,000 members. Consensus laboratory routines order sets were electronically introduced into all physicians’ computerized medical record (CMR) software, after consensus and internal marketing process. The primary findings were that a previously observed annual increase in laboratory test utilization was stopped, a 2% reduction in total number of tests and a 4% reduction in the total number of tests per age adjusted person was observed. In conclusion the wide use of CMRs and communication technology combined with an appropriate organizational process can be used to increase appropriate utilization of laboratory tests.