Unpaired data

Unpaired Data Consider two samples, A and B, for which mean values, Xa and Ab, and standard deviations, sa and sb, have been measured. Confidence intervals for Pa and Pb can be written for both samples... 

Figure 6. Semi quantitative evaluation of spontaneous adsorption of collagen IV conjugated with a fluorescence marker Oregon Green 488 (A) to polyethylene foils iradiated with ions (energy 30 keV, dose from lO to lO ions/cm ), and its correlation with the number of rat aortic smooth muscle cells initially adhering to the polymer on day 1 after seeding (B). Collagen was diluted in phosphate-buffered saline to the concentration of 0.02 mg/ml (10 pg/cm ) and incubated with the foils for 24 h at room temperature. Mean+SEM from 4-9 experiments. Student t-test for unpaired data [43].

Figure 8. Concentration of markers of adhesion (A) and differentiation (B) in rat aortic smooth muscle cells in cultures on polyethylene (PE) modified by irradiation with ions (energy 30 keV, doses from lO to lO ions/cm ). Measured by enzymatic immunosorbent assay (ELISA) per mg of protein, absorbances expressed in % of the values obtained on pristine non-modified PE. Mean + SEM from 4 experiments. Student t-test for unpaired data, p<0.05 p<0.01 compared to the values on pristine PE.

Describe the difference between paired and unpaired data... 

Use with unpaired data Unjustified and pointless Correct procedure... 

The following parameters may be determined inulin clearance (GFR), single nephron GFR, fractional delivery of water, sodium and potassium in proximal and distal tubules and in urine. All data are expressed as mean values SEM. Comparison of the effects of compounds to be tested with controls is performed by one way analysis of variance and by Student st-test for paired and unpaired data. 

Statistical analysis of the data is performed by means of the Student s t-test for paired or unpaired data, or by means of analysis of variance followed by the Tukey test. Statistical analysis of nonparametric data is made by the chi square test. 

Means standard error of the mean are calculated. Statistical evaluation is performed by using Student s t-test for paired or unpaired data. 

COMPARISON OF PpbB AND RS APPROACHES 42.3.1 Paired Versus Unpaired Data... 

Figure 42.2 illustrates the results obtained with the RS approach using paired and unpaired data at different replication levels (i.e., Mi equals 10,100, and 500 to build up the population pool). This was then followed by a calculation of TPAR over M2 (i.e., 50) virtual studies (with N = IS for each study). Across all three population pool levels (i.e.. Mi = 10, 100, and 500), paired observations consistently yielded tighter distributions than unpaired ones. Similar results were obtained with the PpbB approach. 

FIGURE 42.3 Comparison of the performance of the RS and PpbB approaches when tissue-to-plasma AUC ratios (TPAR) are computed from paired and unpaired data. The comparison is focused on distribution of the first and third quartiles (Q1 and Q3, respectively) of TPARs. 

Statistically significant (Student s t-test for unpaired data) at p<0.05. 

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