Go Back   Science Forums Biology Forum Molecular Biology Forum Physics Chemistry Forum > Molecular Research Topics Forum > Bioinformatics > BioStatistics Forum
Register Search Today's Posts Mark Forums Read

BioStatistics Forum Post Questions and Discuss Biostatistics Programs and Stastistical Analysis Questions


How to do the normalized survival analysis?

How to do the normalized survival analysis? - BioStatistics Forum

How to do the normalized survival analysis? - Post Questions and Discuss Biostatistics Programs and Stastistical Analysis Questions


Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 07-21-2009, 07:04 PM
Pipette Filler
Points: 632, Level: 12 Points: 632, Level: 12 Points: 632, Level: 12
Activity: 0% Activity: 0% Activity: 0%
 
Join Date: May 2009
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Default How to do the normalized survival analysis?



We have GraphPad Prism 5 and could not find how to get this analysis done. Basically, say we have 4 groups in survival analysis. These are wild-type in control, wild-type in toxin, mutant in control and mutant in toxin treatment. We want to know if this mutant has different (vs wild-type) life-span in toxin treatment. The tricky part is that the effect of the toxin treatment must be normalized (or corrected) with the control treatment first since the mutant might have different survival already without toxin treatment. So how should we do this normalized survival analysis?
Please let us know how this could be done and hopefully there is also a reference for your solution. Thanks a lot.
Reply With Quote
  #2  
Old 10-06-2009, 06:38 AM
Pipette Filler
Points: 14, Level: 1 Points: 14, Level: 1 Points: 14, Level: 1
Activity: 0% Activity: 0% Activity: 0%
 
Join Date: Oct 2009
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: How to do the normalized survival analysis?

For normalization, we mean to adjust data in order to conform to the assumption of normal distribution or standardisation. There are two main applications of normalization, 1) to eliminate variations of scores in repeated measures on the same response variable on the same subject. 2) to convert different scale sets into a common scale. In your case, it is nothing to do with normalization. In fact, your study is a two-factor design (forms of species and treatments). That means, you are looking for whether forms of species and treatments would have any effect on the life span. There will be three possible results, 1. Both forms and treatments would affect the life span, i.e. interaction effect, or 2. Only species forms would affect the life span, or 3. Only treatments would affect the life span. For survival analysis, you may use Cox Regression. But if there is no censored data on your study, which survival analysis is specialized at, then you may use two-way ANOVA instead which is more easy to interpret the result.
Reply With Quote
  #3  
Old 10-07-2009, 06:16 AM
Pipette Filler
Points: 14, Level: 1 Points: 14, Level: 1 Points: 14, Level: 1
Activity: 0% Activity: 0% Activity: 0%
 
Join Date: Oct 2009
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: How to do the normalized survival analysis?

For normalisation, we mean to adjust the data in order to conform to assumption of normal distribution or standardisation. For example, 1. adjust repeated measures of each subject to remove variations between mesaures within subject, 2. to standarise the score sets of different scales into a common scale. In your study, it seems normalisation is not right choice. More appropriately speaking, you are working on a two-factor design, which looking for whether the species' forms (wild-type and mutant) and the treatment types (control and toxin) would have affect the life span. In such case, there will be three possible outcomes, 1. both forms and treatments would afffect life span differently (i.e. interaction effect), 2. only forms would affect the life span, 3. only treatments woul affect the life span. You may conduct a cox regression to test it. Or if there is no censored data which survival analysis is specialised at, then you may consider to use two way ANOVA which is more easy to inteprete the result.
Reply With Quote
  #4  
Old 10-08-2009, 02:51 AM
Pipette Filler
Points: 14, Level: 1 Points: 14, Level: 1 Points: 14, Level: 1
Activity: 0% Activity: 0% Activity: 0%
 
Join Date: Oct 2009
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: How to do the normalized survival analysis?

Normalisation is not meant for the purpose. Your research in fact is a two-factor design which looking for whether the forms of species (wild-type and mutant) and treatments (control and toxin) would affect the life span. You may conduct cox regression or if no censored data, you may use two-way ANOVA which more easy to inteprete the result.
Reply With Quote
Reply

Tags
analysis , normalized , survival


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Human Cytome Project - Update 24 Jan. 2005 Peter Van Osta Cell Biology and Cell Culture 1 08-01-2010 02:18 PM
Resource: Mass Spectrometry-based Methods of Proteome Analysis danfive Protein Science 0 06-02-2008 08:03 PM
Trainings/Projects on Bioinformatics,Molecular Biology,MicroBiology,DrugDesigning and SAS Programming at Global Institute of Biotechnology Global Institute of Biotechnology Protocols and Methods Forum 0 11-28-2007 12:31 PM
qPCR NEWSLETTER - October 2006 Editor www.Gene-Quantification.info Protocols and Methods Forum 0 10-26-2006 12:25 PM
Sci.chem FAQ - Part 7 of 7 Bruce Hamilton Chemistry Forum 0 01-15-2004 09:13 AM


All times are GMT. The time now is 09:15 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2005 - 2012 Molecular Station | All Rights Reserved
Page generated in 0.16035 seconds with 16 queries