Turbidimetric: Antibiotic turbidimetric assay

Description Usage Details Source References Examples

Description

5.1.3. FOUR-DOSE RANDOMIZED BLOCK DESIGN

Usage

1
data("Turbidimetric")

Details

From Ph.Eur.:

This assay is designed to assign a potency in international units per vial. The standard has an assigned potency of 670 IU/mg. The test preparation has an assumed potency of 20 000 IU/vial. On the basis of this information the stock solutions are prepared as follows. 16.7 mg of the standard is dissolved in 25 ml solvent and the contents of one vial of the test preparation are dissolved in 40 ml solvent. The final solutions are prepared by first diluting to 1/40 and further using a dilution ratio of 1.5. The tubes are placed in a water-bath in a randomized block arrangement (see Section 8.5). The responses are listed in Table 5.1.3.-I. Inspection of Figure 5.1.3.-I gives no rise to doubt the validity of the assumptions of normality and homogeneity of variance of the data. The standard deviation of S3 is somewhat high but is no reason for concern.

Source

The example can also be found at CombiStats - EDQM, Council of Europe (http://combistats.edqm.eu): http://combistats.edqm.eu/content/view/188/199/

References

Chapter 5.3. Statistical analysis. In EUROPEAN PHARMACOPOEIA version 8.0, 2014; 607-635.

Examples

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data(Turbidimetric); Data <- Turbidimetric

Data <- readAssayTable(paste(system.file(package = "pla"),
                             "vignettes/PhEur/data/AntibioticTurbidimetric.txt",
                             sep = "/"))
plaModel <- plaRBD(Data,
                   assayTitle = "PhEur: Antibiotic turbidimetric assay")
plaModel
plots    <- plot(plaModel)

Example output

Note: Two factors without labels:  Sample, Dose .
================================================================================
Project: Europ. Pharm., 5th Ed. (2005), Ch. 5.3, 5.1.3
Assay: Antibiotic turbidimetric assay
================================================================================
================================================================================
Data values:
--------------------------------------------------------------------------------
     S:1:1 S:2:2 S:3:3 S:4:4 T:1:1 T:2:2 T:3:3 T:4:4
1    252.0 207.0   168 113.0 242.0 206.0 146.0 115.0
2    249.0 201.0   187 107.0 236.0 197.0 153.0 102.0
3    247.0 193.0   162 111.0 246.0 197.0 148.0 104.0
4    250.0 207.0   155 108.0 231.0 191.0 159.0 106.0
5    235.0 207.0   140  98.0 232.0 186.0 146.0  95.0
Mean 246.6 203.0   162 107.4 237.4 195.4 150.4 104.4
SD     6.7   6.2    17   5.8   6.5   7.5   5.6   7.2
CV     2.7   3.0    11   5.4   2.7   3.8   3.7   6.9
================================================================================
================================================================================
Dilution ration: 1.5 
Factor: 1 0.005 0.00558584323889534 
Significance level alpha: 5 %
================================================================================

================================================================================
Regression, Restricted model (Common Slope), with adjusting for 'blocks'.:
--------------------------------------------------------------------------------

Call:
lm(formula = Response ~ -1 + factor(Sample) + factor(Replicate) + 
    Z, data = data)

Residuals:
   Min     1Q Median     3Q    Max 
-9.530 -4.247 -0.695  3.009 26.580 

Coefficients:
                   Estimate Std. Error t value Pr(>|t|)    
factor(Sample)S     117.435      3.256  36.068  < 2e-16 ***
factor(Sample)T     109.485      3.256  33.627  < 2e-16 ***
factor(Replicate)2   -2.125      3.687  -0.576 0.568246    
factor(Replicate)3   -5.125      3.687  -1.390 0.173781    
factor(Replicate)4   -5.250      3.687  -1.424 0.163810    
factor(Replicate)5  -13.750      3.687  -3.730 0.000719 ***
Z                  -111.255      2.572 -43.262  < 2e-16 ***
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Residual standard error: 7.373 on 33 degrees of freedom
Multiple R-squared:  0.9987,	Adjusted R-squared:  0.9984 
F-statistic:  3523 on 7 and 33 DF,  p-value: < 2.2e-16

--------------------------------------------------------------------------------
Slope:
        Z 
-111.2549 
================================================================================

================================================================================
Regression, Unrestricted Model (Different slopes), with adjusting for 'blocks':
--------------------------------------------------------------------------------

Call:
lm(formula = Response ~ -1 + factor(Sample) + factor(Replicate) + 
    factor(Sample):Z, data = data)

Residuals:
   Min     1Q Median     3Q    Max 
-9.885 -3.683 -1.565  3.141 26.935 

Coefficients:
                   Estimate Std. Error t value Pr(>|t|)    
factor(Sample)S     116.370      3.642  31.950  < 2e-16 ***
factor(Sample)T     110.550      3.642  30.352  < 2e-16 ***
factor(Replicate)2   -2.125      3.717  -0.572 0.571557    
factor(Replicate)3   -5.125      3.717  -1.379 0.177558    
factor(Replicate)4   -5.250      3.717  -1.412 0.167514    
factor(Replicate)5  -13.750      3.717  -3.699 0.000809 ***
factor(Sample)S:Z  -113.006      3.667 -30.815  < 2e-16 ***
factor(Sample)T:Z  -109.504      3.667 -29.860  < 2e-16 ***
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Residual standard error: 7.435 on 32 degrees of freedom
Multiple R-squared:  0.9987,	Adjusted R-squared:  0.9984 
F-statistic:  3032 on 8 and 32 DF,  p-value: < 2.2e-16

--------------------------------------------------------------------------------
Slopes:
factor(Sample)S:Z factor(Sample)T:Z 
        -113.0060         -109.5039 
================================================================================


--------------------------------------------------------------------------------
Randomized Block Design Analysis (RBD):
--------------------------------------------------------------------------------
Analysis of Variance Table

Response: Response
                                Df Sum Sq Mean Sq   F value    Pr(>F)    
factor(Replicate)                4    877     219    4.0653  0.010099 *  
factor(Sample)                   1    632     632   11.7224  0.001921 ** 
Dilution                         1 101746  101746 1887.1109 < 2.2e-16 ***
factor(Sample):Dilution          1     25      25    0.4675  0.499766    
factor(Sample):factor(Dilution)  4    259      65    1.2016  0.332090    
Residuals                       28   1510      54                        
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
                     Df  Sum Sq Mean Sq  F value      Pr(>F) DFresiduals
Test of Preparation:  1 632.025 632.025 11.72239 0.001920815          28
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                Df Sum Sq  Mean Sq  F value     Pr(>F) F(critical)
Test of Blocks:  4 876.75 219.1875 4.065346 0.01009903    2.714076
                This test passes if F(Blocks) < F(critical)
Test of Blocks:                               (Test failed)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                    Df   Sum Sq  Mean Sq  F value       Pr(>F) F(critical)
Test of Regression:  1 101745.6 101745.6 1887.111 3.068778e-27    4.195972
                    This test passes if F(regression) > F(critical)
Test of Regression:                                    Test passed!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                   Df Sum Sq Mean Sq F value    Pr(>F) F(critical)
Test of Linearity:  4 259.14  64.785 1.20159 0.3320901    2.714076
                   This test passes if F(non-linearity) < F(critical)
Test of Linearity:                                       Test passed!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                     Df Sum Sq Mean Sq   F value    Pr(>F) F(critical)
Test of Parallelism:  1 25.205  25.205 0.4674858 0.4997658    4.195972
                     This test passes if F(non-parallelity) < F(critical)
Test of Parallelism:                                         Test passed!
================================================================================
================================================================================
Sums of Squares, Slope, Variance, C, Potency and Confidence-intervals:
--------------------------------------------------------------------------------
        SStot         SSreg         SSres         SSsmp             R 
1.0504837e+05 1.0174560e+05 1.5096500e+03 6.3202500e+02 9.8720618e-01 
         Radj 
9.8650990e-01 
        DFres             b            s2            qt             C 
  28.00000000 -111.25494919   53.91607143    2.04840714    1.00222844 
            V 
   0.41100488 
       WidthT -    Log(Lower)T -  Log(Potency)T -    Log(Upper)T -  
     0.042932889      0.028683845      0.071457495      0.114549623 
          CMT -  
     0.071616734 
                      exp(Width)        Lower      Potency        Upper
1                   1.0438678373 1.0290991887 1.0740724965 1.1213682855
0.005               0.0052193392 0.0051454959 0.0053703625 0.0056068414
0.00558584323889534 0.0058308821 0.0057483867 0.0059996006 0.0062637875
                         exp(CM)
1                   1.0742435445
0.005               0.0053712177
0.00558584323889534 0.0060005560
--------------------------------------------------------------------------------
================================================================================

pla documentation built on May 2, 2019, 11:12 a.m.