medical statistics

Hello all, I wonder if you can help me understand the following comment I received on a study: So, there are 3 patient groups (A, B and C): Group A receives treatment X Group B receives treatment Y Group C received treatment Y followed by treatment Z. Results (the numbers are made up)...

Hello, my name is Andy and I am racking my brain with the following research question: Let's assume you are a surgeon who wants to remove a tumor which is exactly in the middle of the abdomen. The tumor is surgically accessible from a left flank approach or right flank approach in general...

Hello everyone, I am studying immue cell distribution in different types of nontomourous (n=66), precancerous (n=67) and malignant tissues (n=48) in a single patient cohort. As you can see in the violin plot attached below, I started out by applying the K-W test to compare the distribution in...

Hi all! I am interested in estimating drug treatment effects in a crossover design where I have a baseline, week 20 and week 40 measurements (1. univariate; 2. multivariate) for a set of 30 patients. 15 of these patients were treated with active medication during the first phase (baseline to...

I need to assess agreement between to variables. The problem is that one of the variable is a continuous variable and the other is a categorical variable. I create a test that gives a certain value to a the compression of the brain. The gold standard test gives a categorical value among...

Hi guys. I'm doing a meta-analysis of survival based on a blood marker, and not all the studies have provided a multivariate hazard ratio. Some have given a univariate hazard ratio (usually where it is not significant) and I would like to put them into the random effects analysis also. Should I...

We have measured the concentration cesium-137 in the tissue of 15 tunafish. We may consider the distribution as normal distribution and a 95 % Confidence Interval for the mean concentration was calculated to (5.03 to 6.71) (Bq/kg). Is the following statement true or false: "The interval means...

As part of my final year Bsc degree I am writing a research proposal. HOWEVER I am struggling to wrap my head round which statistical test would best suit my data. The Research is an RCT with an intervention and a control group (2 groups). I would like to compare the incidence rate of...

I'm a complete nube, never programmed in my life and downloaded R two days ago. Trying to upload a data table in R to stackoverflow for help with data analysis. Recommended to use "dput" could someone explain in easy to understand terms how to do so.

Hello I'm Sean a final year medical student doing an audit on some ultrasound data. I'm new to programming and R. What I want to do is create a column of data based off the values in three other columns. I have attached a picture to refer to because its a bit difficult to describe So I...

Hi everyone, I am an English person who's never taken statistics (yikes, right?). Well, now I'm working a job where I need some ideas of what kinds of statistical analysis might be used to make sure that medical devices (heart monitors in this case) are working properly. I'm writing a...

Hi all, In a large registry dataset of psychiatric patients, if one wants to find the excess risk of schizophrenia patients developing depression, what would be the best method to apply: 1) Use the relevant formula to calculate PAF (Population Attributable Fraction). Formula can be...

Hi TalkStats I have data from a project. The data is the blood pressure for each participant at day of "baseline" visit, and 3 time points after baseline visit. Index these baseline and post-baseline time points j=0,1,2,3. For the ith participant, at time point j, we have measurement...

Hello, I am very new to statistical analysis, but am very excited to to be learning it. I am working on finding reference ranges for some mammalian blood work. I hope this is the appropriate place to post my query, otherwise, my apologies. I have successfully found my reference ranges...

Hello, I am currently doing a study into factors that affect mortality in a particular type of bacterial infection. I would like to compare certain patient characteristics. One of which is the specialty that the patient is under. I currently have a variable in SPSS that has three values...