How to calculate sample size for a study conducted to evaluate a new treatment technique ??

A new treatment will be used to treat only one group and the results will be evaluated... How to set a sample size for such study??

04 May 2017 7,918 2 View

What is the type of this sampling technique?

I would like to ask about sampling technique. My study aimed to collect data about physical activity among university students. To be representative to all students we decided to use multistage...

10 November 2016 1,582 8 View

How can I design and calculate Multistage stratified clustered sample?

31 December 2015 6,837 5 View

How optimize the Size Exclusion Chromatography?

Hello! I'll do a size exclusion chromatography, but I only have an open column, and I'll perform the peptide extraction from yeast, using buffer lysis (sodium phosphate 50 mM/NaCl 30 mM/DNAse and...

01 March 2021 2,215 2 View

No title

01 March 2021 3,905 5 View

What test should I use to compare two or three means, if data is not normally distributed but sample size is > 30 in each group?

I personally feel this as a most confusing question. As per my understanding, if sample size is > 30, and sample is skewed, we can still use paramteric approach, as it will follow Z...

01 March 2021 1,587 6 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

Can polymer concentrations be calculated based on the number average molecular weight?

Hello, I spin-cast two different polymers onto wafers and measure their height as a function of initial concentration. For polymer A, I have the weight-average molecular weight (Mw) as well as...

28 February 2021 7,882 2 View

Why there are two peaks while using the mie plot of Silver nanoparticle?

Hi, I am trying to learn the theoretical modelling of silver nanoparticle using the Mie scattering theory. After that, I discovered a software named Mieplot developed by Philip Laven, where it...

25 February 2021 7,493 6 View

How to increase solubility of Poly acrylic acid in Dioxane solvent?

I am working with Polyacrylic acid (100.000Da) and instead of water, I need to use another solvent (dioxane) to dissolve PAA. However, because of the high molecular weight, it's quite hard to...

25 February 2021 2,225 5 View

How to calculate Z (the number of molecules in a unit cell) for calculating theoretical density?

I am trying to calculate the theoretical density of my ceramics materials. I use the formula below to calculate the theoretical density: Theoretical density = (Molecular weight x No. of molecules...

24 February 2021 3,823 2 View

How to handle studies which report perfect effect sizes in a meta-analysis using Pearson's r?

I'm in the process of updating a meta-analysis and in one of the new studies, effect sizes are reported as Tau-U. Two of the effect sizes are reported as Tau-U = 1.00. I am using Andy Field's...

24 February 2021 2,265 3 View

Sample size determination for non-parametric tests?

How do I run a a priori sample size determination for non-parametric tests, like the Mann-Whitney U-test and the Kruskall-Wallis or other non-parametric tests that accord with the unpaired t-test...

24 February 2021 166 6 View