OBJECTIVES: Diagnostic laboratory tests may add critical information to guide treatment and improve patient outcomes, but payers have often questioned its value.  We reviewed the methodology and results of published cost-utility analyses (CUAs) of laboratory tests through 2008. METHODS: We screened all papers related to laboratory diagnostic tests in the Tufts Medical Center Cost-effectiveness Analysis Registry (www.cearegistry.org) which contains detailed information on over 2,000 published CUAs from 1976 to 2008.  In addition to the standard auditing process, we recorded information on the reported test accuracy and IVD cost.  We also captured whether any account was taken for potential value (or harm) unrelated to treatment consequences such as the “reassurance value of testing” or additional anxiety produced by test information. RESULTS: We identified 141 published CUAs pertaining to diagnostic laboratory tests, which contained 433 separate incremental cost-effectiveness ratios (ICER).  The number of publications has increased rapidly in recent years.  The most common areas of clinical application were hematology/oncology (n=42, 29.8%), and OB/GYN (n=36, 25.5%).  Approximately 63% (89/141) of studies addressed the accuracy of the test.  Only 10% (14/141) mentioned test safety or associated risks.  A small number (n=13, 9.2%) of CUAs mentioned or considered the potential value or harm of testing unrelated to treatment consequences.  Over 55% of the reported ICERs were either dominant (more QALYs for less cost), or below $50,000 per QALY gained (in $US 2008). CONCLUSIONS: The number of CUAs evaluating laboratory tests technologies has increased substantially with applications to diverse clinical areas.  The vast majority of CUAs have not attempted to measure the potential value or harms of diagnostic testing unrelated to treatment.