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. 2012 Jan 30;15:3. doi: 10.1186/1758-2652-15-3

Table 1.

Laboratory Pima™ testing using venous blood

Phase I
EDTA venous blood
Pima #1 Pima #2 Pima #3 Pima #4 All
Pima DATA
N 53 61 59 58 100**

Range of CD4 counts* 2-1297 4-1217 5-1190 7-972 4.5-1235

Mean CD4 count* 349 334 354 317 318

%Similarity to Predicate
(%SIM Mean ± SD)
99.26 ± 5.34 99.15 ± 5.35 99.64 ± 6.42 97.17 ± 5.01 98.17 ± 4.57

%SIM CV# 5.38% 5.40% 6.44% 5.16% 4.66%

BA Bias* ± 1 STDev
(PIMA - PLG)
(95% CI of bias mean)
-14.38 ± 37.9
(-23.8 to -3.9)
-11.05 ± 42.4
(-21.9 to 0.19)
-13.6 ± 53.3
(-27.5 to 0.22)
-22.6 ± 40.3
(-33.2 to -12.0)
-17.3 ± 36.7
(-24.0 to -10.03)

BA 95% LOA* -88.7 to 59.9 -94.1 to 72.1 -118.2 to 90.8 -101.6 to 56.4 -89.4 to 54.7

Statistical analyses across four Pima™ analysers tested in the laboratory during Phase 1 using a fixed 20 mm3 volume of manually pipetted EDTA venous blood and compared against predicate flow cytometry (PLG/CD4). All values, with the exception of N, refer to CD4 cell counts in cells/mm3. BA = Bland-Altman statistical analysis. LOA = limits of agreement. #Precision of Pima™ to Predicate method expressed as %SIM CV.

*cells/mm3

**The average Pima/CD4 value was used for comparison to predicate CD4 where more than two simultaneous Pima values were obtained.