Please make more of these types of videos. It is very rare to find someone who can do a thorough job of explaining a complicated subject and make it engaging at the same time.
Thank you for your comment George! We are currently working on creating a video series to cover the core concepts of Evidence-Based Medicine in effort to help clinicians and other healthcare providers become well informed consumers of the medical literature.
@@ossyn5704 Thank you so much for your kind feedback Ndi Mu Kulah. It is my pleasure to provide only the highest quality educational experience for my learners. We are working on producing a library of content that will available online.
Your feedback lets me know that I am moving in the right direction as an educator and content creator. Thank you Kerri. Keep an eye out for more content in the future!
thank you so much Dr. McCoy for explaining this topic in great details but still easy to understand! hats off to the best explanation video about HR on youtube!
This was a FANTASTIC video! More medical students need videos like this breaking down high impact journal articles and teaching the basic principles of some of the most utilized statistical concepts. I'd encourage you to make more of these videos as this was truly fantastic.
You said it right "Work Smart and not Hard" and of course we need more videos like this from smart people like you. I am a grad student learning these new concepts. The best video ever. Thank you!
Thank you for your feedback Divya. We are currently working on placing a library of content online, so stay tuned. And good luck with your grad studies!
Wow ! Definitely ONE of the Best Video I’ve watch on Biostatistics! Subject matter presented in a simple and succinct way ! Thank you so very much Dr McCoy! Please keep making those videos ! You are much appreciated ! 😊
Thank you ron finn. I am working on converting the content I teach to my University students and my conference educational sessions into a format available on UA-cam.
Thank you so much Kartik! It is my pleasure to provide only the highest quality educational experience for my learners. We are working on a library of content online . . . the video series you are waiting for is on the way!
Thank you very much for this video! I have no stats/medical background and I was able to get a general understanding about the purpose of Kaplan Meier curves and Hazard ratios. Your videos are so engaging and make a topic like this really interesting 🎉
Thank you so much Dr. McCoy. I remember you from the McMaster EBP workshop, so I am not surprise at all to see such an amazing explanation about the theme. I would be more than pleasure to see more videos about EBM explain by you. Best regards. Yesenia from Mexico
Thanks Dr. Mccoy! I needed this for some analysis on ED boarding and mortality for broke. I was very surprised to see your handsome mug on here... but this was perfect.
Thank you for your feedback Secilia! It is my pleasure to provide only the highest quality educational experience for my learners. We are working on producing a library of content that will be available online.
Hello Javier. I teach multiple courses, one of which is clinical epidemiology and biostatistics for the school of medicine. This video was originally intended for my medical students . . . however I quickly discovered that more than just my students were gaining benefit from the educational offering. Thank you for the feedback.
It is important to point out that the term 'probability' is often used, through technically incorrect to describe the likelihood of an event at a given time point t. Rather, it is the likelihood of event at time t conditional on the passage of time from observation start to t minus 1. But, great video.
I am very glad to view this. A lot of confusion cleared in less than one hour. To Dr McCoy...more grease to a born teacher. Do u have other videos on the other medical statistics topics? Kindly let me know
Sir, thanks alot for coming up with such an awesome presentation, i couldn't believe myself that I've listened to the whole video without pausing ..... thanks again for making it so engaging :)
What a wonderful video! I have been trying to find out if my approach to a research question is stupid: 1. I asked what is associated with whether or not someone dropped out of school during their pregnancy using a logistic regression followed by 2. A cox regression that was ought to give me more information as to when (measured in weeks) something happened during their pregnancy in terms of dropout. Now, the hazard ratio and odds ratio are quite similar -- which is expected, I suppose, given that the hazard ratio assumes proportionality. For instance, the logistic regression showed that those who do not have caregiver support are 3 times more likely to drop out during pregnancy (odds ratio = 3) and the hazard ratio for that same variable is 3 as well. As far as I understand, the hazard ratio means that dropping out for those without caregiver support is three times more likely than those for caregiver support at any given time. Since this needs to be proportionate between groups, this '3' would be expected to be similar to the odds ratio from regression or not? My question is: What is the added value of the cox regression in addition to the logistic regression that I already have? Could I use the logistic regression to identify variables that I then test over time in a cox regression ??? THANK YOU!!!!!
One of the key variables that distinguishes a hazard ratio from say, an odds ratio, is the time to the event. If all you are interested in is whether an event occurred, then measures of effect such as odds ratios or risk ratios should suffice. However, if you are also interested in the time until that event . . . then Kaplan Meier curves and hazard ratios will likely be the pathway for you.
wow, you really broke this down into its finer details- very cool! thank you!! ^_^.. not gonna lie, I did watch this veryy passively and somewhat as background noise/while multitasking/but still visually following along every now n then lol.. so.. I'll definitely be back for a more focused view :) - thanks sm for treating this just as you did and for not feeling the need to give into some weird youtube fodder (try-hard funny stuff??..). it can be a bit distracting and i feel, most often, out of place most of the time >_< .. so, definitely also very much appreciate that aspect!.. I'm new to your content and channel so I'm not sure if you're familiar with public speaking or know your way around delivering lectures and such.. but, having sat through a bad class or two.. lol, if neither of those were already in your wheel-house, then I'd say you definitely have a knack for it! Your pacing and delivery-the natural conversational tone with its natural ebbs n flows-really allow for an easy-listen and an un-stressed focus. (ykno, as opposed to too monotone, stark script reading, or unnatural pauses in odd places.)--... welp.. not sure how to end this now! lol..and i've gotten quite lazy lmao-- i/g in youtube or in internet fashion: k baiii ^_^
That is undoubtedly one of the best presentations I have heard on this topic. Relevant, clear and lucid with just the right pace. Thank you! Any similar videos on critical medical literature review?. Covering types of trials and meta-analysis?
Thank you Natalia. It is my pleasure to provide only the highest quality educational experience for my learners. We are working on producing a library of content that will be available online.
Thank you deba! We are working on providing a library of content online for our learners. Regarding the 95% CI content, this video was originally intended for students in my epidemiology and biostatistics class where all of their content is posted internally (University). I wanted to post one or two of their videos online to check how many students watched the content before class. Little did I expect several thousands of viewers to watch and appreciate the content! We have content on point estimates and 95% CI slated for our larger online viewing community. Stay tuned!
You mention at the 36 minute mark a link to a tutorial on inferential statistics, and particularly confidence intervals, but I don't see this anywhere, could you share this please?
7:58 So during this interval someone died, ánd someone disappeared from the research population, losing two subjects all together? And so to survive you need 1) not to do and 2) not to be censored?
Hello Frits. If the outcome under study is death, that will be recorded as an event. If a patient was not known to suffer an event AND you no longer have information about them (they were loss to follow up), they are censored.
As a general rule of thumb, the greater the number of patients censored (in relation to the total number of patients experiencing an event of interest as well as the total number of patients in the study) the less confidence we may have in the accuracy (and precision) of the estimates provided by the curves.
How are you calculating the instantaneous hazard rate that is then put into ratio of both groups? In the video, you just use .2 as an example to explain the concept and in the first paper you analyze it just says .55 with no justification. Also, how can we assume that the hazard ratio is the same throughout the duration when clearly upon inspection we can see that the step sizes change dramatically at different times?
Thank you for your interest S 117. The hazard is the instantaneous risk of event in a particular group (calculated for both the treatment and control group). The Hazard Ratio is the ratio of these two Hazards. As with virtually every statistical model, there are assumptions. The proportional hazards assumption is so vital in Cox regression that it is a part of its name . . . the Cox proportional hazards model. In a nut shell, its means that although the hazard rates can change with time (both the treatment and control group), the ratio of hazards is constant.
![Survival Analysis [Simply Explained]](http://i.ytimg.com/vi/Wo9RNcHM_bs/mqdefault.jpg)
Please make more of these types of videos. It is very rare to find someone who can do a thorough job of explaining a complicated subject and make it engaging at the same time.
Thank you for your comment George! We are currently working on creating a video series to cover the core concepts of Evidence-Based Medicine in effort to help clinicians and other healthcare providers become well informed consumers of the medical literature.
Thank you very much Sir! Your 52 minute video has taught me what I have been struggling to master in 4 years. Bless you!
@@ossyn5704 Thank you so much for your kind feedback Ndi Mu Kulah. It is my pleasure to provide only the highest quality educational experience for my learners. We are working on producing a library of content that will available online.
The first time in 30 years that I find a clear explanation of these topics. Thank you, yours is a gift to translate complexity in simple words.
Thank you for your kind comments Adolfo! Stay tuned as we are working on a library of content coming soon!
You tube should allow for the opportunity to give more than one upvote in a genuine way. That was excellent!
You explained this in detail, but concisely, you explained it in layman terms, but without losing the integrity of the statistics. I'm in awe :)
Your feedback lets me know that I am moving in the right direction as an educator and content creator. Thank you Kerri. Keep an eye out for more content in the future!
thank you so much Dr. McCoy for explaining this topic in great details but still easy to understand! hats off to the best explanation video about HR on youtube!
This was a FANTASTIC video! More medical students need videos like this breaking down high impact journal articles and teaching the basic principles of some of the most utilized statistical concepts. I'd encourage you to make more of these videos as this was truly fantastic.
That's material of so many books put together in a crisp video. thanks a ton
My pleasure Brototo Deb. Keep an eye out for more content to come!
You said it right "Work Smart and not Hard" and of course we need more videos like this from smart people like you. I am a grad student learning these new concepts. The best video ever. Thank you!
Thank you for your feedback Divya. We are currently working on placing a library of content online, so stay tuned. And good luck with your grad studies!
This is THE explanation of Kaplan Meier curves I've been searching everywhere for! Thank you!
Wow ! Definitely ONE of the Best Video I’ve watch on Biostatistics! Subject matter presented in a simple and succinct way ! Thank you so very much Dr McCoy! Please keep making those videos ! You are much appreciated ! 😊
In my 7 years of SAS programmer experience i never see this much clear explanation on Kaplan Meier concept. Thank you so much.
Thank you so much for expalining a complex thing in a simple way....Thanks a ton!!!
This is the best explanation of Kaplan meiere and hazard ratio.
It was my pleasure Nosheen. We are working on proving a library of similar content online for our learners . . . so stay tuned!
You deserve way more subscribers for this kind of content. Outstanding.
Thank you ron finn. I am working on converting the content I teach to my University students and my conference educational sessions into a format available on UA-cam.
This is much better explained than in a stats textbook. thanks.
My pleasure Robert! Keep an eye out as we are working on a library of similar content to share!
cant believe my senses. So nicely explained. Would have taken life time to understand otherwise. Eagerly waiting for a video series
Thank you so much Kartik! It is my pleasure to provide only the highest quality educational experience for my learners. We are working on a library of content online . . . the video series you are waiting for is on the way!
Thank you very much for this video! I have no stats/medical background and I was able to get a general understanding about the purpose of Kaplan Meier curves and Hazard ratios. Your videos are so engaging and make a topic like this really interesting 🎉
This is such a well thought out video! The best and most concise explanation of Kaplan Meier I've seen thus far 👌
Was my pleasure Danza. We are working on a library of content to post online. If you enjoyed this one . . . there will be much more to come!
I agree, he explained it very well
Extremely helpful and intelligant explanation ... thanks Eric... keep flooding our knowlege with such fantastic easy material.
Excellent and easy explanation ... It helped me a lot Thank you
Excellent video, well executed and engaging! Thank you so much
Thank you! Statistics is so hard for me to comprehend and connect clinically. You made it so easy!!
EXCELLENT VIDEO, YOUR EXPLAIN VERY CLEARLY AND UNDERSTANDING WAY
My pleasure! We are working on producing a library of content that will available online.
Wonderful! Congratulations on the very didactic video!
Thank you for this video. Its long but very worth it
You are genius.
Jajak Allahu akhair
From Bangladesh
Great explanation. Simply and concisely
Your feedback is appreciated Javier!
Excellent video and so very well explained. I wish my lectures at the university were half as good as yous. Thank you.
Thank you so much Dr. McCoy. I remember you from the McMaster EBP workshop, so I am not surprise at all to see such an amazing explanation about the theme. I would be more than pleasure to see more videos about EBM explain by you. Best regards. Yesenia from Mexico
youtube should be paying this kind of vids more than music ones.
Amazing lecture! I have been struggling a lot on this matter, thank you very much Eric. Keep it up
Thank you very much, I don't typically leave comments on youtube, but this is REALLY helpful
Wow. Very well explained. Req pl share the links of other videos
Wow explaining is crystal clear! Saved my finals (med student from Taiwan here~
excellent sir
Thank you! We are working on a library of similar Evidence-Based Medicine content to share!
Very informative video. Every second was well spent. Thank you Eric!
Thank you for your time Jenny. Keep an eye out as there is more content on the way!
Very clearly explained.
Thank you Surendra!
Great detailed presentation!
Very useful!
Much appreciated! 👍
My pleasure!
Thanks Dr. Mccoy! I needed this for some analysis on ED boarding and mortality for broke. I was very surprised to see your handsome mug on here... but this was perfect.
Thank you so much !!!! it helped me a lot , please keep making videos like this one ,it really helped me to understand everything.
You are a beast! one of the GOATs
Excellent video
Glad you enjoyed it Hunter!
Wow.. this video is the real McCoy..(pun intended). Great video Dr McCoy! Thanks for sharing your knowledge!
I am glad you enjoyed and gained value from the content Ahmad! We are working on posting more content online, stay tuned!
Thank you for the clear video and simple explanations.I real understand.I appreciate it in 2020
Thank you for your feedback Secilia! It is my pleasure to provide only the highest quality educational experience for my learners. We are working on producing a library of content that will be available online.
Great explanation, thanks!
I do like this video! Excellent explanation!
Thank you so much Roger. Keep an eye out for more content in the future. We are working on a library!
This is a super good tutorial. Thank you Eric
Excellent video, so helpful!
Glad you enjoyed it Daniela! There will be more educational videos to come!
It is my goal to provide you the learner with educational value that exceeds your expectations.
Self-explanatory and well taught video!! Thanks for clearing all the doubt I had..
This is my first UA-cam comment. Excellent tutorial!!!
I'm glad you enjoyed it Saif! We are working on posting a library of similar content - coming soon!
Thank you for your valuable information
Wooooow , very detailed explanation doc
Glad you enjoyed it! We are working on a series of Evidence-Based Medicine core content videos - coming soon!
Incredible.Gained so much clarity.Thank you :D
Thank you for watching and for your feedback Ritwik. We are working on providing a library of similar content . . . so stay tuned!
do you have only one video of this style? This video is excellent! You should have many many more! Greetings from Argentina and thank you!
Hello Javier. I teach multiple courses, one of which is clinical epidemiology and biostatistics for the school of medicine. This video was originally intended for my medical students . . . however I quickly discovered that more than just my students were gaining benefit from the educational offering. Thank you for the feedback.
thank you so much for this brilliant explanation!!! I finally understood Kaplan Meier curve and hazard ratio. Best regards from Germany
THANK YOU SO MUCH SIR........LOTS OF LOVE..........
It is important to point out that the term 'probability' is often used, through technically incorrect to describe the likelihood of an event at a given time point t. Rather, it is the likelihood of event at time t conditional on the passage of time from observation start to t minus 1. But, great video.
Superb👍👍
My pleasure George John!
wow!! amazing vid, you are the best...please make more vids
I am very glad to view this. A lot of confusion cleared in less than one hour. To Dr McCoy...more grease to a born teacher. Do u have other videos on the other medical statistics topics? Kindly let me know
Hello Emeka, yes, we are working on a library of Evidence-Based Medicine topics similar to this one with plans to share online. Keep an eye out!
Sir, thanks alot for coming up with such an awesome presentation, i couldn't believe myself that I've listened to the whole video without pausing ..... thanks again for making it so engaging :)
Thank you soooo much. It makes much more sense now!
Amazing explanation! Very helpful
Thank you deepesh varma. We are currently working on a library of similar content to share!
Very good video. When are your other videos coming?
Thank you Devesh. Keep an eye out as more content is on the way.
What a wonderful video!
I have been trying to find out if my approach to a research question is stupid:
1. I asked what is associated with whether or not someone dropped out of school during their pregnancy using a logistic regression followed by
2. A cox regression that was ought to give me more information as to when (measured in weeks) something happened during their pregnancy in terms of dropout.
Now, the hazard ratio and odds ratio are quite similar -- which is expected, I suppose, given that the hazard ratio assumes proportionality.
For instance, the logistic regression showed that those who do not have caregiver support are 3 times more likely to drop out during pregnancy (odds ratio = 3) and the hazard ratio for that same variable is 3 as well. As far as I understand, the hazard ratio means that dropping out for those without caregiver support is three times more likely than those for caregiver support at any given time. Since this needs to be proportionate between groups, this '3' would be expected to be similar to the odds ratio from regression or not?
My question is: What is the added value of the cox regression in addition to the logistic regression that I already have?
Could I use the logistic regression to identify variables that I then test over time in a cox regression ???
THANK YOU!!!!!
One of the key variables that distinguishes a hazard ratio from say, an odds ratio, is the time to the event. If all you are interested in is whether an event occurred, then measures of effect such as odds ratios or risk ratios should suffice. However, if you are also interested in the time until that event . . . then Kaplan Meier curves and hazard ratios will likely be the pathway for you.
OMG this was amazing as a conceptual video. I got it down now just need to figure out the technical part on SPSS.
wow, you really broke this down into its finer details- very cool! thank you!! ^_^.. not gonna lie, I did watch this veryy passively and somewhat as background noise/while multitasking/but still visually following along every now n then lol.. so.. I'll definitely be back for a more focused view :) - thanks sm for treating this just as you did and for not feeling the need to give into some weird youtube fodder (try-hard funny stuff??..). it can be a bit distracting and i feel, most often, out of place most of the time >_< .. so, definitely also very much appreciate that aspect!.. I'm new to your content and channel so I'm not sure if you're familiar with public speaking or know your way around delivering lectures and such.. but, having sat through a bad class or two.. lol, if neither of those were already in your wheel-house, then I'd say you definitely have a knack for it! Your pacing and delivery-the natural conversational tone with its natural ebbs n flows-really allow for an easy-listen and an un-stressed focus. (ykno, as opposed to too monotone, stark script reading, or unnatural pauses in odd places.)--... welp.. not sure how to end this now! lol..and i've gotten quite lazy lmao-- i/g in youtube or in internet fashion: k baiii ^_^
Brilliant Lecture!Thanks!!
The pleasure is all mine Kurvari!
Helpful lecture! I kept thinking the baby in the background was my toddler waking up. O.O
Best video EVER!
excellent
My pleasure Renee!
Thank you very much! Your video helped me a lot.
Thanks alot. Very useful video 👌
My pleasure Gaiti! Keep an eye out as we are working on a library of similar content to share!
Outstanding!!!!
Thank you Huboshi!
That is undoubtedly one of the best presentations I have heard on this topic. Relevant, clear and lucid with just the right pace. Thank you!
Any similar videos on critical medical literature review?. Covering types of trials and meta-analysis?
Thank you so much for the video! Really help a LOT
Thank you Natalia. It is my pleasure to provide only the highest quality educational experience for my learners. We are working on producing a library of content that will be available online.
Awesome lecture, well done
Thank you very much. An awesome lecture
My pleasure Fauzi! More content is on the way!
Great thanks!
I'm glad you enjoyed it Andy! More awesome content to increase your knowledge base and skill set is coming soon!
@@christophermccoy1134 I better subscribe in that case!
@@andyablett1466 Awesome! Thank you Andy!
Thank you sir for explaining it so nicely. This was of great help.🙏
My pleasure Sayantani. Thank you for the feedback. Keep an eye out for more content to come!
could you explain regresion partitional analysis?
Well Explained.... Please make more such videos on statistical analysis. Where can I get you video on 95% CI?
Thank you deba! We are working on providing a library of content online for our learners. Regarding the 95% CI content, this video was originally intended for students in my epidemiology and biostatistics class where all of their content is posted internally (University). I wanted to post one or two of their videos online to check how many students watched the content before class. Little did I expect several thousands of viewers to watch and appreciate the content! We have content on point estimates and 95% CI slated for our larger online viewing community. Stay tuned!
Thanks very well explained
My pleasure! More content coming soon!
Thank you! This is wonderful!
My pleasure. We will be sharing more Evidence-Based Medicine content similar to this in the future!
Thank you ! this is quite helpful !
My pleasure!
Very helpful. Thank you !!!
I can understand this! yeah! Where is the link for the other videos? Do you have a tutorial on Confidence Intervals? Thank you.
excellent , thank you so much
Great video ! Can you make it same for objective response rate ?
Glad you enjoyed it Nirmal! More content to come!
Thank you, Eric. At last, I get it!
Thanks a lot for the great lecture. I used some points and pictures for my presentation if you don't mind
Awesome doc!! Jawline on point
Glad you enjoyed it Jasreen!
Brilliant!
My pleasure! More leaner oriented content coming soon!
You mention at the 36 minute mark a link to a tutorial on inferential statistics, and particularly confidence intervals, but I don't see this anywhere, could you share this please?
thank you very much. this was helpful.
My pleasure blanchard mbay! We are working on creating a library of similar content . . . stay tuned!
Great video! thank you!
Thank you for watching Alexei. More content to come!
thanks for your lecture!
My pleasure! More content to come!
7:58 So during this interval someone died, ánd someone disappeared from the research population, losing two subjects all together? And so to survive you need 1) not to do and 2) not to be censored?
Hello Frits. If the outcome under study is death, that will be recorded as an event. If a patient was not known to suffer an event AND you no longer have information about them (they were loss to follow up), they are censored.
in the druvalumab study as shown... wasn't there too much censoring in the pfs curve? How do we intepret that?
As a general rule of thumb, the greater the number of patients censored (in relation to the total number of patients experiencing an event of interest as well as the total number of patients in the study) the less confidence we may have in the accuracy (and precision) of the estimates provided by the curves.
How are you calculating the instantaneous hazard rate that is then put into ratio of both groups? In the video, you just use .2 as an example to explain the concept and in the first paper you analyze it just says .55 with no justification. Also, how can we assume that the hazard ratio is the same throughout the duration when clearly upon inspection we can see that the step sizes change dramatically at different times?
Thank you for your interest S 117. The hazard is the instantaneous risk of event in a particular group (calculated for both the treatment and control group). The Hazard Ratio is the ratio of these two Hazards. As with virtually every statistical model, there are assumptions. The proportional hazards assumption is so vital in Cox regression that it is a part of its name . . . the Cox proportional hazards model. In a nut shell, its means that although the hazard rates can change with time (both the treatment and control group), the ratio of hazards is constant.
Eric McCoy thank you for your response, you are a wonderful educator!