Accusport/Accutrend Lactate Accuracy Information


The accepted method of validating a new instrument to measure lactate is to take simultaneous measurements from a subject and then to compare the results of the test instrument (in this case, the Accusport/Accutrend Lactate Portable Lactate Analyzer) with an instrument of known accuracy. Except for one study conducted on hospital trauma patients, all the Accusport readings were made on people while they were exercising. At the same time an additional measurement was taken using an instrument with established validity. The Accusport portable lactate analyzer and the Accutrend Lactate analyzer use the same technology. The tests below were conducted by various organizations in the United States and Europe to validate the accuracy of the Accusport.

Tests 1 and 2 were conducted for the European introduction of the Accusport.

Test 1 Testing Mode Regression Equation Correlation
Coefficient
Sample
Size
Range
mmol/l
4 Sites Whole Blood Accusport = .994 TCL + 0.055 R = .969 N = 418 .8 - 18
Comments Blood was sampled from each ear. One sample was used for the Accusport the other sample was used for the Test Combination Lactate for Sports Medicine (TCL). The TCL is a fully enzymatic photometric method. A blood drop was used for the Accusport while 20 µl of blood was used for the TCL.

Test 2 Testing Mode Regression Equation Correlation
Coefficient
Sample
Size
Range
mmol/l
6 Sites Plasma Accusport = .949 TCL - 0.039 R = .982 N = 617 .7 - 25
Comments Blood was sampled from each ear. One sample was used for the Accusport the other sample was used for the Test Combination Lactate for Sports Medicine (TCL). A blood drop was used for the Accusport. Capillary blood was centrifuged within 1 minute and deproteinated with perchloric acid. The resultant plasma was measured by the TCL.


Test 3, 4 and 5 were conducted for the US introduction of the Accusport.

Test 3 Testing Mode Regression Equation Correlation
Coefficient
Sample
Size
Range
mmol/l
Lot 1 Whole Blood Accusport = 1.014 TCL - 0.1 R = .991 N = 98 .7 - 15
Lot 2 Whole Blood Accusport = .972 TCL + 0.4 R = .989 N = 98 .7 - 15
Comments Deproteinized capillary whole blood was used as the reference. The TCL was used on the EPOS analyzer. Samples were from earlobes.

Test 4 Testing Mode Regression Equation Correlation
Coefficient
Sample
Size
Range
mmol/l
Lot 3 Whole Blood Accusport = .999 YSI - 0.5 R = .966 N = 108 .9 - 17
Lot 4 Whole Blood Accusport = .913 YSI + 0.1 R = .954 N = 108 .9 - 17
Comments Hemolyzed capillary whole blood was used as the reference. The YSI Sport 1500 was used as the reference device. Samples were taken from finger tips.

Test 5 Testing Mode Regression Equation Correlation
Coefficient
Sample
Size
Range
mmol/l
Lot 1 Plasma Accusport = .971 TCL - 0.2 R = .98 N = 98 .5 - 20
Lot 2 Plasma Accusport = .946 TCL + 0.3 R = .984 N = 84 1 - 21
Comments Deproteinized capillary plasma was used as the reference. The TCL was used in the manual method on a photometer. Samples were from earlobes.


Tests 6, 7, and 8 were presented at the 1996 American College of Sports Medicine meeting.

Test 6 Testing Mode Average Value Correlation
Coefficient
Sample
Size
Range
mmol/l
Lot 1 Whole Blood Accusport = 4.95; YSI = 5.44 R = .934 N = 96 .5 - 17
Lot 2 Whole Blood Accusport = 5.03; YSI = 5.44 R = .954 N = 96 .5 - 17
Comments Testing was conducted during a graded exercise test. Capillary whole blood was used as the sample. The YSI was used as the reference instrument. Samples were from finger tips.

Test 7 Lactate
Rest
Lactate
70% VO2
Lactate
Peak
Lactate
1 Min Post
Lactate
5 Min Post
Accusport 1 1.44 2.26 13.17 14.86 12.78
Accusport 2 1.24 2.24 13.95 14.66 12.73
YSI 1500 1.17 2.14 13.21 14.52 13.61
Interclass Correlations .80 .93 .88 .89 .97
Comments 31 well trained cyclists performed a graded exercise test followed by a Wingate anaerobic test. Lactate measurements were taken at rest before the graded exercise test, at 70% VO2 and at Peak power output. After a rest a Wingate test was performed and lactate measurements were taken at 1 and 5 min post test while performing an active recovery. All lactate reading were from capillary whole blood taken from the finger tips. The YSI 1500 was the reference analyzer. The interclass correlations were very high considering that each class represented a narrow range of readings

Test 8 Testing Mode Regression Equation Correlation
Coefficient
Sample
Size
Range
mmol/l
Lot 1 Whole Blood Not Available R = .976 N = 133 .7 - 17
Lot 2 Whole Blood Not Available R = .976 N = 133 .7 - 17
Comments Testing was conducted during a graded exercise test. Capillary whole blood was used as the sample. The YSI 1500 was used as the reference instrument. Samples were from finger tips. The Accusport readings were from 10 different meters and show the reliability of readings across different instruments.


Test 9 was conducted by a major teaching hospital in the Northeast part of the US. The results were presented at the Critical Care Medicine Conference in February 1997.

Test 9 Regression Equation Correlation
Coefficient
Sample
Size
Range
mmol/l
Accusport 1 vs Nova 10 Accusport = .861 Nova + .209 R = .988 N = 63 .10 - 19
Accusport 2 vs Nova 10 Accusport = .929 Nova - 0.095 R = .991 N = 66 .10 - 19
Accusport 1 vs 2 Accusport2 = .92 AS 1 + 0.323 R = .991 N = 63 .10 - 18
Comments This study took place in a hospital trauma center and the subjects were trauma victims. While there were a few high readings, nearly all the readings (57) are under 7 mmol/l. Given this narrow range the high correlations between the two Accusport analyzers and the Nova 10 instrument are very impressive. All readings were of whole blood. The Nova 10 readings were taken by hospital lab personnel and the Accusport readings were taken by a medical student.


Accutrend Lactate Information

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Last update February 27, 2011 All contents Sports Resource Group, Inc.