IRB and patient privacy

Local IRB seems to become very picky nowadays. Recently, one of the local IRBs in New York insists that we can not collect patient's date of birth and initials concerning the patient's privacy. We responded to them that these are the industry standard. Then we tried to find the evidence to demonstrate that collecting the date of birth and initials are indeed the industry standard.

It turns out that some pharmaceutical companies (such as GSK) do not collect the patient initials. So collecting the patient's initials seems not to be an industry standard.

However, we will have to collect the date of birth in order to calculate the age accurately. I found some supporting document in ICH guidance.
In the following ICH guideline E2A (page 11), patients initials and age and/or date of birth are listed as items needed for SAE reporting.
http://www.ich.org/LOB/media/MEDIA436.pdf
Also under the ICH guideline E2B (page 17), it also says for patient identification information "The date of birth should be used if the precise birthday is known; otherwise the age should be used."
http://www.ich.org/LOB/media/MEDIA632.pdf

A joke about statistician

Even thoug this is a joke, I find sometimes it is very true.

A manager wanted to hire someone to work in her department and she had applications from a lawyer, an archeologist, and a statistician. She invited the lawyer for an interview and asked just a single question, "What is one plus one?" The lawyer explained "In matters of commercial law, the Supreme Court precedent in 1867 established that, in matters of commercial law, one plus one is considered to be prima facie evidence of equaling two." The manager was very impressed. Then she invited the archeologist for an interview and asked the same question. The archeologist replied, "Although many ancient cultures had solid concepts of numbers, the concept of addition was first established in the Egyptian culture, circa 2000 B.C. and it was at the tomb of Amenhotep that the first written evidence was found to establish that one plus one was equal to two." Again the manager was very impressed. She then invited the statistician in and asked "What is one plus one?" The statistician looked around very carefully, then went up and closed the door, lowered the window shades, and asked very quietly "What do you want it to be?"

Sample size considering the drop out rate

Thanks for my colleagure who point out my mistake in calculating the sample size adjusting for the drop out rate. According to the sample size calculation, we estimated that 100 subjects would be needed to detect the statistical differences. Considering 20% drop out rate, what is the # of subjects to be randomized?
It is not 100 + 100*20% = 120
It should be 100 / (1-0.2) = 125
It means that with 125 randomized subjects, if 25 subjects (20% of 125) drop out, we still have 100 subjects left. This is correct way to adjust for the drop out rate.

SAS PROC CDISC

I am surprised to know that there is a SAS procedure for CDISC. Is this procedure really working?

http://support.sas.com/rnd/base/topics/sxle913/fieldresponse.htm#cdiscdoc

A naive question

Question:

I have 3 samples which were each measured for protein content of IgG, and several other proteins (in mgs/ml). As you can see, all three of my samples for IgG do not fall within the acceptance limits, everything else looks fine. For my purposes, I am less interested in whether the exact mg/ml range specifications have been met.
I am more interested in knowing if the ratio of IgG to Total Protein is consistent. Since measurements of total protein, and each individual protein, have limits (unequal ranges), is it possible to derive the ranges for IgG/total protein ratios?

IgG: sample1=0.9213, sample2=0.8769, sample3=1.5984
Acceptance limit (+/- 4SD): low=0.15, high=0.79

Total Protein: sample1=31.635, sample2=32.856, sample3= 34.299
Acceptance limit (+/- 4SD): low= 29.2, high= 36.4

As before if the Acceptance limits are (for IgG): 0.15 and 0.79, the mean would be 0.47 (s= 0.08) (and for total): 29.2 and 36.4, the mean would be 32.8 (s=0.9) if I make a ratio of the means 0.47/32.8 = 0.014 , what is the new standard deviation? (I can assume the number of measurements made for each mean are the same).

Response:

I understand you are trying to derive the standard deviation, therefore the acceptance limit for ratio based on the standard deviation of the numerator and the denominator. But this approach does not work mathematically or statistically. You can calculate the mean/standard deviation for numerator is 0.47 (0.08) and for the denominator is 32.8 (0.9). But there is no statistical formula for deriving the standard deviation for the ratio. If the numerator and denominator follows the normal distribution, the ratio will NOT follow the normal distribution.
To calculate the standard deviation for IgG/total Protein ratio, you would need to calculate the ratio for each sample first.
ratio1, ratio2, ..., ration
SD of ratio = square root of (sum of (each individual ratio - mean of ratio)/n)

A probability issue

If a country implements a family planning policy as below:

If the first child is a boy, no second child is allowed.
If the first child is a girl, a second child can be allowed and no third child is allowed.

Will the sex ratio (male/famale) still be 1?

Interim Analysis

In a recent meeting with some investigators, we discussed the protocol for a phase II clinical trial. When I ask whether or not if we need to consider the interim analysis, several investigators immediately oppose it citing that it will cost us the p-values. It seems that the investigators have been well informed the multiplicity and alpha-spending issue for the interim analysis or multiple look at the data.

I have a feeling that investigators seems to be afraid of the interim analysese because it may cost the power for the final analysis.