Can Log-rank p-value be valid when group size is very small and have no events?

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Could you recommend any books about Number Theory?

Beginner level books. High level books. Analytical Number Theory. Algebraic Number Theory. Combinatorical Number Theory. Books about partitions. Books about primes.

03 March 2021 7,174 5 View

Why is the efficiency of viral mRNA electroporation in PBMC low?

Hello, I have been struggling with the electroporation of PBMC with HIV-I mRNA. Although the quality of the RNA generated is good, and the handling of the cells in meticulous, the frequency of...

27 February 2021 9,233 3 View

Have anyone checked before Cyclic voltammograms of intial ITO substrate and E-teck?

As a beginner in electrochemistry, I tried to obtain cyclic voltamograms of commercial anatase powder deposited on an ITO substrate or on Eteck. After several attempts, I noticed that my cyclic...

23 February 2021 3,175 3 View

The type of filter paper used to filter an epoxidized oil (the mixture is an epoxidized oil with magnesium sulfate) ?

I have a mixture of epoxidized oil and magnesium sulfate wich type of filtre paper should i use

21 February 2021 3,944 3 View

Any information about dinitrosalisylic acid reagent end point color stability ?

I work on estimation of alpha amylase activity using dinitrosalisylic acid reagent If i put the reagent to stope the enzymatic reaction and allow the reagent to react with the produced reducing...

17 February 2021 7,402 4 View

Is There are any idea to achieve H NMR signals for swollen compound ??

the samples are not completely soluble - just swelled the solvents that's mean the sample may be partially soluble any suggestion, please

16 February 2021 8,801 3 View

Is there association of SARS-CoV-2 infection rate with meteorological factors?

There are contradictory research papers about the correlation between meteorological parameters and incidence of COVID-19 in some countries worldwide. Is there correlation between the...

15 February 2021 5,806 2 View

Are there alternatives to the Devarda alloy when estimating nitrogen?

Are there alternatives to the Devarda alloy when estimating nitrogen? devarda alloy is reducing the nitrate to ammonium

15 February 2021 8,838 3 View

Can the viability assays (ex: MTT/CCK-8) measure cell proliferation? or are they solely viability assays?

I want to conduct a proliferation assay to test a chemotherapy combination on a cancer cell line. At first, I thought about the MTT assay. But now, all sources are saying that these do not measure...

14 February 2021 3,142 7 View

Using liquids as superstrate in Fabry-Perot Cavity Antenna?

Hi, A Fabry Perot Cavity allows to increase the directivity of a low gain antenna by putting in the top of cavity a superstrate with high permittivity such as a ceramic (er=10.2). However,...

09 February 2021 6,799 8 View

How to manually calculate p value in ANOVA? what is the equation or formula for it?

03 March 2021 4,928 5 View

Is it necessary to report effect size (ES) in statistics of biomedical research given that we already report p values routinely?

Pls share your thoughts

01 March 2021 7,330 4 View

Is it possible that Cancer cells could survive in heparinized blood for 48 hours?

Hi everyone, I am just wondering if we incubated 200 microliter of whole blood with 50 microliter of cancer cells(1bout 5000cells) do you think that cancer would survive for 48 hours?

23 February 2021 3,840 3 View

How to perform Kaplan-meier survival analysis in SPSS?

Hi everyone, This is my first time of attempting to run survival analysis. I have a data on patients with End-stage Kidney Diseases (ESKD). I would want to run survival probability by treatment...

16 February 2021 2,647 3 View

How to perform Cox proportional hazard analysis or Kaplan-meier survival analysis in SPSS?

At first please see the attachment. This experiment was performed for a period of 7 days (n=100). After 7 days, we found different level of survival rate (%) for each treatment. Now, I want to...

15 February 2021 9,145 2 View

Any model suggestion for the Electronic Health Records dataset ?

I have sequentially measured the time-series Electronic Health Record patient dataset. This is 7 years of research and each patient's blood pressure, Hba1c, LDL, Hb, Baseline Age,...were measured...

09 February 2021 4,933 8 View

How to properly reach normality in residuals with lmer?

Hello, I have a large non-balanced panel dataset regarding a company dealing with private lessons for students. My goal is to fit a lmer model which predicts the number of monthly hours taken by a...

08 February 2021 2,539 7 View

How to conduct Meta-analysis of Survival Curves without Control Group?

I am conducting a Meta-analysis where I have data of only survival plots. I am stuck on performing meta-analysis on it because there is no control group for the studies. How should I perform...

07 February 2021 7,394 3 View

How could I get the P-value from the mean, SEM, and n of different groups in the t-test?

How could I get the P-value from the mean, SEM, and n of different groups in the t-test without the original data? For detail, I would like to know the P-value between BMP-2: 50ng/ml group and the...

06 February 2021 6,539 4 View

How to compare expected and counted values statistically with different p values for each genotype?

Hey there, I am currently working on the statistics of counted and expected genotypes in mice litter of a mutant mouse model. I have two different mutated genes, both alone and in combination, one...

03 February 2021 6,408 2 View

Muhammad Yousaf

Dear Sofia El Aissaoui

Please read the following article. It may be helpful for you as I hope that you will get the required material.

http://www.sthda.com/english/wiki/survival-analysis-basics

Good luck

Best regards

Dr. Muuhamad Yousaf

David Eugene Booth

Given the major difference between the two groups wouldn't a Kaplan Meier plot suffice. Best wishes David Booth

Sofia El Aissaoui

Thank you Dr. Muuhamad Yousaf, thank you Dr. David Eugene Booth, I truly appreciate your answers. Thank you very much!

In this "humble" study, working on prognostic factors, I want to show the significance of survival difference of variables between groups if it exists.

Thank you