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Then for the other people, just assign them a page or 2 to do, and have them build the sheet

from scratch in their favorite software – WITHOUT LOOKING AT THE CODES IN THE EXCAL SHEET

UNDER TEST. It is very critical that they do it from the Appendix. Have them call me or email if

they get stuck. The sheets were:

1.

QUAL SLV – No Ref method comparison

2.

QUAL SLV UNPAIRED

3.

QUAL SLV PAIRED

4.

QUAL COLLAB UNPAIRED

5.

QUAL COLLAB PAIRED

The calculations for confidence intervals are the tricky parts, although we also need to check all

the calcs for mean PODs and dPODs. In addition, people may have difficulty finding the correct

formulae for these confidence intervals, due to the fact that there are several, and also due to

the fact that we have added some since publishing the Appendix. Here’s my best shot at

identifying where the formula are:

1.

QUAL SLV – No Ref method comparison

CI calcs are given in Appx J, Annex C, very first section on the left of the page.

2.

QUAL SLV UNPAIRED

Calcs are Appx J, Annex C, immediately following the above section, starting at lower left, it

gives calcs for dPODs then on the upper right, gives the calcs for the CIs for dPODs. For this

sheet, you have 2 methods, so you calc POD values (and CIs) for both methods as done in sheet

1, then calculate dPOD and CIs on the dPOD as given here in this section of Annex C.

3.

QUAL SLV PAIRED

This one is not in the annex and is discussed in the ppt file we presented at the meeting in

Dallas. The section of Annex C called “dPOD for Paired Studies” will need to be changed to

incorporate the info in the ppt file.

4.

QUAL COLLAB UNPAIRED

This one is in the Annex F – we have modified it slightly though in 2 areas.

We have found in our work in the ISO group that the very complicated Welch-Satterthwaite

estimation for df for the t-based interval is not necessary and the formula df = L-1 works just as

well for the collab sizes we are using. So p. 17 of the Appendix J, Annex F, that df calculation can

be simplified to just df = L-1, or degrees of freedom is number of labs minus one.

The second thing we found was better was to change how we switch from the t-based CI to the

binomial-based CI calculator. Originally, we decided to do this based on the POD value, but in

simulations, it seems to provide a more seamless transition if it transitions not on POD, but on x,

the number of positive hits. For this new version, the Appendix will need to be changed. See

ISO Draft standard or call Paul on this.

Then in addition, you will need to calculate s(R) and s(r) and s(L) for the data. So this will be

Qualitative Micro Validation Proposed Plan