Response following a single dose
18 important questions on Response following a single dose
What are reasons for the time delay (the gap between the plasma concentration and the response)?
- pharmacodynamics:
- systems in flux: when the site of meassurements is in another compartment than the site of action.
What 2 reasons can be a cause for the delay of the response after the concentration?
By what kind of factors is the time of onset of response govered?
- absorption
- distribution to target site
- Higher grades + faster learning
- Never study anything twice
- 100% sure, 100% understanding
For my 1st exam I got a C. Then, I started looking for ways to learn better and I came across Study Smart. Since then I have scored a A+, A, A- and another A. I highly recommend it to everyone who wants to hear it. I am so happy with it!!
I was struggling to finish all my first-year subjects for 3 years. Then I discovered Study Smart, which helped me to finish all of them within 3 months.
Because of StudySmart, things are going well in many ways. Before, I always had study stress and no time for anything. Now I feel calm and confident (because of the program). I used to score a B, now I usually score an A or A+.
Hey Chris, I really want to thank you very much for developing the platform, I usually got around C for my exams, now I scored an A+, an A and a A- !!
Since using Study Smart, my average has increased significantly. I even completed a statistics course with a A+ while I'm bad at statistics. I took on extra courses this year, because of Study Smart. Thanks so much!
Ever since I started studying with StudySmart I passed all my exams !!! No more re-sits!! At first, I was happy with a pass and now I only get good grades. Many thanks!
I aced all the courses I studied with Study Smart. For law, I first scored a D, and now an A! I’m 100% sure that I’ll pass all the courses I study with Study Smart.
I always thought I studied well. My grades were fine. I could never have imagined that applying these study skills would have such a huge and direct impact on my grades, my speed and the pleasure I have in learning.
For the first time, I finally feel totally confident about the way I learn. I have the perfect overview and make great progress in terms of speed and the grades I get. Thanks, Chris!
I immediately started to enjoy learning again, and my grades soared. All of a sudden, everything went better. I highly recommend Study Smart to all students..
Being able to create my materials online made the process of studying so much smoother and quicker. I no longer have to spend a huge amount of my time on creating my summaries.
At first, my notes were a mess. Now I use Study Smart to take my notes in a perfectly structured way. It helps me to save a lot of time and do other things I enjoy.
Students that study with Study Smart get better grades. The system applies all the learning methods in such a way that both well-performing students and students who struggle perform much better.
Hi Chris, I would like to thank you very much. Last year I scored C on a course, and this year I got an A+ thanks to your method! Thank you very much!
The largest effect is that my child is more enthusiastic about school! Every parent wants their children to be happy at school, Study Smart made it happen.
In high school, I failed several exams, and that has really changed now. I actually needed this tool very much back then. Since I started studying with StudySmart, I haven't had any D's. My average score is now an A and those are results I would have never had in the past
With my old method, I passed only 3 out of 8 courses. Since I started taking my notes digitally in Study Smart, I have passed all my courses on the first try. For me, StudySmart takes away the stress of wondering if I will pass or not.
Thanks to StudySmart, I passed all my exams, and with better grades than before! On top of that, I have mastered a very good study method now, which I am confident will help me earn my degree.
What are the PK variables?
So, there has to be 1 equation with 7 unknown variables.
What is target AUC dosing?
This is not feasible in daily clinical practice because of patient discomfort and costs. So this is not efficient.
What kind of methods can be used to determine optimal sampling?
- Monte Carlo simulations: This requires pharmacokinetic population models.
So what is the step plan in the experimental approach?
2) divide patients into 2 groups: calculate the AUC from the limited samples of the study group and use the other group as validation group for the selecting of optimal sampling times.
What is the classical approach for the study group?
- Calculate the relation between C and AUC by multiple regression analysis. e.g. for 2 data points. repeat this for any combination of data points.
What is the classical approach for the validation group?
-Calculate for each subject the true AUC using all data points
-Calculate for each subject the estimated AUC using the equation for each combination of data points.
- calculate the root mean squared error (RMSE) (measure of precision)
How goes the evaluation according to the classical approach?
- select minimal number of samples needed (so that acceptable precision and minimal sampling times are obtained)
What are limitations and drawbacks of the classical approach?
- The number of data points are limited so a limited accuracy.
- A measurement at exact time point is required what is difficult in practice.
- it is sensitive to outliers so a limited precision
- The true AUC is not exact so a limited accuracy
- there are many calculation so it really takes time.
What are the improvements since the classical approach?
- A replace multiple regression analysis by Bayesian estimation of PK parameters. This means that you have a best estimate of CL, F and AUC.
- Automatic calculation
How is the first step of the Monte Carlo simulation performed? (generation of data)
in between: random noise (interindividual variability)
b) individual PK parameters (for each subject)
in between: PK model, dose, time schedule
c) true plasma concentrations (at time points of measurement)
in between: random noise due to assay error
d)This results into a measured plasma concentration
How is the second step of the monte carlo analysis (analysis of dat) performed?
in between: you perform analysis
b) you have an estimated AUC
in between: you compare the estimated AUC with the true AUC
c) evaluation
Of course you also have a mean error and a root mean squared error which are a measure of bias and a measure of precision, respectively during the evaluation.
How are accuracy and precision defined?
precision: All datapoints are may be wide scattered but the mean value is near to the expected value. It is represented by the RMSE (root mean squared error)
What is the formal definition of accuracy?
bias = lack of accuracy
What is the formal defiinition of precision?
What are the advantages of the Monte Carlo simulation?
- unlimited number of measurements
- exact AUC known
- data of all patients used (for PK population model)
- study design can be chosen freely
The question on the page originate from the summary of the following study material:
- A unique study and practice tool
- Never study anything twice again
- Get the grades you hope for
- 100% sure, 100% understanding
