Ability of a test to improve health outcomes
that are relevant to the individual patient.
The clinical effectiveness of BNP testing for
diagnosis of heart failure in patients presenting to emergency with acute
dyspnea were investigated in RCTs that compared the addition of BNP testing
with standard investigations alone followed by routine care. A meta-analysis of
these RCTs reported that addition of BNP testing decreased length of hospital
stay by ~1 day; possibly reduced admission rates, but did not affect 30-day mortality
A description of typical
processes of care in managing a specific condition in a specific group of
Clinical pathways by NICE in the UK
Ability of a biomarker to conform to predefined
clinical specifications in detecting patients with a particular clinical
condition or in a physiological state.
Diagnostic test: In patients presented to emergency with chest pain and low to intermediate likelihood for ACS, the hs-cTnT assay was compared with a conventional cTnT method and CT angiography as the gold standard for diagnosing ACS. At the optimal hs-cTnT cut point of 8.62ng/L, sensitivity for ACS was 76% and specificity was 78%, and hs-cTnT above the 99th percentile strongly predicted ACS. Compared with the conventional cTnT method, hsTnT detected 27% more ACS cases.
Prognostic test: In elderly patients presenting to primary care with symptoms of heart failure the risk for cardiovascular mortality (adjusted for age, sex, impaired estimated glomerular filtration rate, and anaemia) increased 2.5-fold with a plasma NT-proBNP concentration >507 ng/L; 2-fold with hs-cTnT >99th percentile; 3-fold when both biomarkers were elevated.
A cost-effectiveness analysis compares the
changes in costs and in health effects of introducing a test, to assess the
extent to which the test can be regarded as providing value for money.
Point of care testing (PoCT) in general
practice: A cost-effectiveness analysis based on an RCT of nearly 5,000
patients followed up for 18 months in Australian general practices compared the
incremental costs and health outcomes associated with a clinical strategy of
PoCT for INR, HbA1c, lipids, and albumin:creatinine ratio (ACR) to those of
pathology laboratory testing. Under base-case assumptions, PoCT was more
cost-effective and effective for ACR than standard pathology. For HbA1c, POCT
was more expensive but also more effective than standard pathology with an
incremental cost-effectiveness ratio of $40 per patient maintained in the
therapeutic range, while INR was more costly but less effective and therefore