Comparison of four methods to measure haemoglobin concentrations in whole blood donors (COMPARE): A diagnostic accuracy study

Abstract

Objective To compare four haemoglobin measurement methods in whole blood donors. Background To safeguard donors, blood services measure haemoglobin concentration in advance of each donation. NHS Blood and Transplant's (NHSBT) customary method have been capillary gravimetry (copper sulphate), followed by venous spectrophotometry (HemoCue) for donors failing gravimetry. However, NHSBT's customary method results in 10% of donors being inappropriately bled (ie, with haemoglobin values below the regulatory threshold). Methods We compared the following four methods in 21 840 blood donors (aged ≥18 years) recruited from 10 NHSBT centres in England, with the Sysmex XN‐2000 haematology analyser, the reference standard: (1) NHSBT's customary method; (2) “post donation” approach, that is, estimating current haemoglobin concentration from that measured by a haematology analyser at a donor's most recent prior donation; (3) “portable haemoglobinometry” (using capillary HemoCue); (4) non‐invasive spectrometry (using MBR Haemospect or Orsense NMB200). We assessed sensitivity; specificity; proportion who would have been inappropriately bled, or rejected from donation (“deferred”) incorrectly; and test preference. Results Compared with the reference standard, the methods ranged in test sensitivity from 17.0% (MBR Haemospect) to 79.0% (portable haemoglobinometry) in men, and from 19.0% (MBR Haemospect) to 82.8% (portable haemoglobinometry) in women. For specificity, the methods ranged from 87.2% (MBR Haemospect) to 99.9% (NHSBT's customary method) in men, and from 74.1% (Orsense NMB200) to 99.8% (NHSBT's customary method) in women. The proportion of donors who would have been inappropriately bled ranged from 2.2% in men for portable haemoglobinometry to 18.9% in women for MBR Haemospect. The proportion of donors who would have been deferred incorrectly with haemoglobin concentration above the minimum threshold ranged from 0.1% in men for NHSBT's customary method to 20.3% in women for OrSense. Most donors preferred non‐invasive spectrometry. Conclusion In the largest study reporting head‐to‐head comparisons of four methods to measure haemoglobin prior to blood donation, our results support replacement of NHSBT's customary method with portable haemoglobinometry.

Early detection of anaemia in primary care with haemoglobinometry: ANHEMOG clinical trial protocol

“…The haemoglobinometer is a portable, pocket-sized device that can be easily transported to patients' home. It is very simple to use and can be operated by any health professional with minimal training [14][15][16] . The technique consists of pricking the patient's finger, collecting a drop of capillary blood with a micropipette and depositing it on a test strip inserted into the device [24].…”

“…Early detection of anaemia contributes to improved quality of life in patients with the clinical profile outlines in this study since we expect to find greater satisfaction among those who are monitored with a haemoglobinometer than those who undergo venipuncture. This expectation is based on the easier and less invasive technique used to obtain the sample [16], as well as lower levels of emotional distress, anxiety and uncertainty that patients experience while waiting for results that will determine what interventions will be necessary since, with a haemoglobinometer, the results are available almost immediately upon taking the sample. Moreover, by monitoring anaemia with a haemoglobinometer, we predict a drop in A&E visits and hospitalizations, thus reducing patients' discomfort and the risks associated with such visits, as well as the health expense they represent.…”

“…There are also portable systems available known as haemoglobinmeters that provide haemogram results in five seconds using just a drop of capillary blood. Clinically speaking, these devices have proven to be accurate and precise in post-anaesthesia care units, intensive care units, hospital A&E and anaemia screening before blood donation [14][15][16].…”

Impact of a post‐donation hemoglobin testing strategy on efficiency and safety of whole blood donation in England: A modeling study

“…The recruited donor population was broadly similar to the general blood donor population of England, notwithstanding some minor differences in age, sex, ethnicity, and donation history. Full details of the original study are available elsewhere 12 . Here, these data serve as a returning donor population in whom baseline characteristics and repeat accurate hemoglobin levels are available.…”

Personalized medicine comes to a blood center near you

“…The earlier Comparison of Four Methods to Measure Hemoglobin Concentrations in Whole Blood Donors (COMPARE) 21 study formed the groundwork for this study. Data from 9360 female and 7948 male donors in COMPARE were used to inform the estimation of parameters in the DES model.…”