Forum: Biostatistics

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Hi all, I have a data set like this: Nematodes copepods Pylochaetes Controle1 1 ...

I am trying to determine the appropriate test to run for a community-based intervention. There are 2 groups (intervention and control) and 2 time...

Hi, all. I'm trying to properly analyze data from an experiment and could use some help bridging the mental gap between statistical theory (which I...

I'm trying to calculate a statistical measure describing the overlap of two sets of proteins. The issue is that the sets are from different organisms...

Does anyone know a good SSPS tutorial for the project I'm doing? I want to do a retrospective study to see if Drug A reduced postoperative...

I have received point estimates from several studies for the prevalence of a rare disease, and I would like to estimate the over-all prevalence in...

Hi I have data from an environmental experiment. We treated a section of river bed to remove an invasive species. I could do with some help...

I want to compare the outcome of two different algorithms applied to one set of MRI images. Each MRI image will be manipulated twice. Once using the...

Dear all, My question can be easily misunderstood, so please allow me to briefly explain the experimental conditions. I have measured a...

Hi, I've been asked to analyze some data and I wanted to get a second opinion on the way I plan to. I have a sample of 8000 teachers. For each...

I would like to predict the response variable using different predictors. So far I have been working with multiple linear regression. However as my...

Hey all, I'm an undergrad statistics student with an interest in causal inference topics such as propensity score analysis and instrument variable...

Hi, First I have to apologise for the probably stupid question, but my statistic knowledge is pretty much 0 and after searching for an answer for...

Hi, I'm trying to use some form of survival analysis (e.g. accelerated failure time or proportional hazards) to study seed germination time. My...

Hi! I'm trying to display some data, let me describe it to you. I have a group of about 5000 teachers. For each teacher, I have the rate of...

Hello, I'm a bit puzzled about competing risks. I've used competing risks methods (gray's test and fine and gray regression) a while ago, but...

I am a clinician working for a community based hospital. A few days ago, my fellow doctor asked me if I could give some advice for her data. ...

Hi, I've been tasked with solving the mean residual life given the density function f(x) and the survival function S(x) I think mean residual...

I'm a Biostatistician working for a researcher who wants to find out if length of training would affect peoples opinion in choosing a certain medical...

Hello all, I am about to receive a very large sample, of around 10 million observations. I will explain. I am requested to statistically analyze...

Dear Stats Folk, I have a one Control group and one patient group. I have measurements on Controls at one time point, while I have a single...

As new to biostatistics I would appreciate some help on the interpretation of ANOSIM results in Primer. Thank you!!...

Hello Forum, Currently I am analyzing results of longitudinal study evaluating the effects of possible dichotomous predictor on continious outcome...

Hello, I have been scratchiong my head for a few days on this problem, which should be pretty simple. I really hope someone can point me in the...

Hello all, How do I make interpretation of odds ratio equal to 0.02, given from a logistic model with a binary outcome and let's say 2 treatments...

Hello all, I ran a model that yields odds ratio, like the logistic regression does. I have received a very wide CI. To illustrate the reason,...

Hello everyone! If I have an outcome (dependent variable) is 3 outcomes (Scale of measurement: categorical/nominal) and the interdependent...

Question about Kaplan-Meier analysis and log rank. I am currently working on a project using the National Cancer Institute's SEER database. A lot of...

Good Morning! I am currently trying to decide which approach to my research question is best. I am using a large data set from a state agency. The...

Hello all! I am working on a multi-level logistic regression (Binary Outcome) model and am trying to finding the best way to check the assumption of...

Hello friends, when i am analysing my data using ANOVA, i came up with a very large cv(55) is there any means to lower it? my design is 4x5 CRD with...

I have measurements basically indicating how much a gene is used in specific individuals. The way you do this is by counting how much gene product...

Hello, I am trying to design a study in which the primary endpoint is time to event. Due to some constraints, the study needs to be a...

Hi everyone, I'm currently doing work with morphometry, working with data I've collected and with an already existing database. At the moment I'm...

Hello, How do I properly report an ANOVA followed by Dunnett's MCT in APA format? Below is the report minitab generates for Effects of Dose on...

I am sorry I am not statistician but I have a very simple (maybe stupid:)) question. I have case group of 4460 and controls of 5085, P value is...

Hello forum, I am seeking your advise. Here is the problem: In a clinical trial, we will collect MRI imaging data from each patient...

Hi friends, What is the correct statistical test to compare a group who was tested in two points in time (pre and post) The same people. I have...

I am trying to analyze data from the longitudinal qualitative scoring of knee joints to measure differences in disease severity by a number of...

Hello, I've run a 2 way ANOVA of my research results and got these 3 p-values: A=0.001, B=0.069, and A*B=0.167. My professor now wants me to remove...

I'm trying to understand a paper on kidney cancer research. The study uses a multivariate Cox regression. The outcome variable is death/no death from...

Please help. I am totally confused about how to show that something is an independent risk factor. I.e. in a cohort study: Group A (n=1000) -...

Hello, I am trying to test whether my choice of link function is correct using the goodness-of-link test. So, firstly since I am testing the...

Hi all, A population of patients were tested for 3 viruses and have a variety of symptom questions associated. For example: ...

Hello All I have a population of 22000 individuals. I wanted to mesure a mean value of a specific parameter. for this purpose I randomly tested...

Hi All - HELP! I have a large dataset on women in labour, and I'm interested in finding out risk factors for a particular complication of labour....

Hi all, I am manually using Holm-Bonferroni method to correct my data as I can't find a way to do it using software. As the data is relatively...

Hi all, I have a set of frequencies for each of the 16 possible nucleotide pairs at a given position in a sequence. I want to test whether any of...

Hello I ran some sample size calculations using Gpower, in order to find the minimum required sample size for the Fisher exact test, since I need...

I was recently reading up on nonparametric alternatives to one way ANOVA and came across a description of ANOVA on rank data...

Hi, I am running up against some problems in my stats analysis. Please can anyone give me a hand on this... I have data on Emergency Department...

Hello everyone, I am trying to figure out which hypothesis test is best for my research. I have two groups of patients (Group 1, n = 726,314...