Bioequivalence and Bioavailability Forum

Main page Policy/Terms of Use Abbreviations Latest Posts

 Log-in |  Register |  Search

Back to the forum  Query: 2017-11-19 11:12 CET (UTC+1h)
 
nobody
Senior

2017-08-07 17:14

Posting: # 17673
Views: 1,350
 

 CVintra for Cmax > AUC, therefore use AUC for sample size? [Power / Sample Size]

Hi again!

Found this here:

https://www.ncbi.nlm.nih.gov/pubmed/28257283

Maybe I need some holiday, after all, but if I understand this correctly, the authors say, CVintra for Cmax is generally higher than for AUC, therefore use AUC to estimate the sample size of your study.

Did I get this right?

Any thoughts on this approach?

Kindest regards, nobody
Helmut
Hero
Homepage
Vienna, Austria,
2017-08-07 18:40

@ nobody
Posting: # 17674
Views: 1,174
 

 CVintra for Cmax > AUC, therefore use AUC for sample size?

Hi nobody,

» Found this here:
» https://www.ncbi.nlm.nih.gov/pubmed/28257283
» […] if I understand this correctly, the authors say, CVintra for Cmax is generally higher than for AUC, therefore use AUC to estimate the sample size of your study.

Ah – the formerly pink, now black journal. ;-)

» Did I get this right?

At least this is what the last sentence of the abstract says: “Hence, CV derived from AUC instead of Cmax should be used in sample-size calculation to achieve a sufficient, yet practical, test power.
”

» Any thoughts on this approach?

Outright bizarre. Since the authors are of a CRO, maybe the love failed studies in order to repeat them? Do you have a copy to share?

[image]Regards,
Helmut Schütz 
[image]

The quality of responses received is directly proportional to the quality of the question asked. ☼
Science Quotes
nobody
Senior

2017-08-07 19:52

@ Helmut
Posting: # 17675
Views: 1,164
 

 CVintra for Cmax > AUC, therefore use AUC for sample size?

» » Any thoughts on this approach?
»
» Outright bizarre.

Good, so I'm not alone...

» Since the authors are of a CRO, maybe the love failed studies in order to repeat them? Do you have a copy to share?

Would not spend a single cent on such a nonsense. How does somethink like that survive peer review?

Now that is published it will be referenced and used as "scientific basis" for further conclusions/studies. Nightmare. How to get such trash retracted?

***deeply depressed***

Kindest regards, nobody
Helmut
Hero
Homepage
Vienna, Austria,
2017-08-07 20:29

@ nobody
Posting: # 17676
Views: 1,156
 

 Crap…

Hi nobody,

» Would not spend a single cent on such a nonsense. How does somethink like that survive peer review?
» Now that is published it will be referenced and used as "scientific basis" for further conclusions/studies.

That’s a slow-burn! My memory-span is better than ElMaestro’s (two weeks?) but it took me a while to recall. I was asked in May 2016 about my opinion. The editor wasn’t even sure whether he should reject the manuscript right away or initiate the review process. My response was: “The manuscript is without any scientific value.” I used some strong words which I won’t post here. Will send it to you by PM.

Obviously the editor didn’t listen to me and the reviewers were blind.
Explains why it is called “blind review”. :angry:

» How to get such trash retracted?

Practically impossible. You could writer a letter to the editor. Detlew and I tried that once, but the procedure was endless and after months (!) the editor of Pharm Res. suggested we should submit a full MS instead. This was not our intention. We didn’t discover anything new. Only wanted to point out that another article (which made it through the review) was pooh.

[image]Regards,
Helmut Schütz 
[image]

The quality of responses received is directly proportional to the quality of the question asked. ☼
Science Quotes
nobody
Senior

2017-08-07 21:31

@ Helmut
Posting: # 17677
Views: 1,132
 

 Crap…

...maybe you should add a special category "Trash science" to the forum to collect such "gems" and make the scientific assessment public via Google...

Kindest regards, nobody
ElMaestro
Hero

Denmark,
2017-08-07 23:04

@ nobody
Posting: # 17679
Views: 1,118
 

 CVintra for Cmax > AUC, therefore use AUC for sample size?

Hi nobody,

» Any thoughts on this approach?

What a load of absolute nonsense.

And it is of a dangerous kind because it:

1. Misleads the guys with spreadsheets into cheaper but seemingly better studies.
2. Increases the likelihood of failure.
= it increases the risk of futile exposure of volunteers.


I am serious, this is deeply problematic cf. e.g. the Helsinki Declaration and the general GCP principles. This is much worse than the recent Midichloria case.
Check the reference list in that publication for a good laugh, by the way.


Edit: Background “Predatory Journals Hit By ‘Star Wars’ Sting” [Helmut]

I could be wrong, but…


Best regards,
ElMaestro

No, I still don't believe much in the usefulness of IVIVCs for OIPs when it comes to picking candidate formulations for the next trial. This is not the same as saying I don't believe in IVIVCs.
nobody
Senior

2017-08-08 10:06

@ ElMaestro
Posting: # 17682
Views: 1,100
 

 CVintra for Cmax > AUC, therefore use AUC for sample size?

...recently saw a nice documentation on the Renaissance. How the "big disrupters" cleaned up the old knowledge and created a completely new "awareness". Same today with all these google-amazon-uber-tesla guys, and then the rest of the world thinks they can do the same with the knowledge in their "field of expertise"...

Kindest regards, nobody
jag009
Hero

NJ,
2017-08-09 06:21

@ nobody
Posting: # 17685
Views: 1,046
 

 CVintra for Cmax > AUC, therefore use AUC for sample size?

» Any thoughts on this approach?

Stay away...

John
nobody
Senior

2017-08-09 17:11

@ jag009
Posting: # 17686
Views: 1,000
 

 CVintra for Cmax > AUC, therefore use AUC for sample size?


Kindest regards, nobody
Back to the forum Activity
 Thread view
Bioequivalence and Bioavailability Forum | Admin contact
17,486 Posts in 3,744 Threads, 1,084 registered users;
23 users online (0 registered, 23 guests).

Errors using inadequate data are much less
than those using no data at all.    Charles Babbage

The BIOEQUIVALENCE / BIOAVAILABILITY FORUM is hosted by
BEBAC Ing. Helmut Schütz
XHTML/CSS RSS Feed