anyone good with biostats, question about CI - USMLE Forums
USMLE Forums Logo
USMLE Forums         Your Reliable USMLE Online Community     Members     Posts
Home
USMLE Articles
USMLE News
USMLE Polls
USMLE Books
USMLE Apps
Go Back   USMLE Forums > USMLE Step 1 Forum

USMLE Step 1 Forum USMLE Step 1 Discussion Forum: Let's talk about anything related to USMLE Step 1 exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 06-09-2015
USMLE Forums Scout
 
Steps History: Not yet
Posts: 12
Threads: 4
Thanked 1 Time in 1 Post
Reputation: 11
Default anyone good with biostats, question about CI

Ok so, I am terrible at biostats...This is so fundamental I am a little embarrassed to post it but I can't find the answer and don't quite know where to look....

When I am looking at a CI, how do I know when the null is 0 vs when it is 1?

For example in most questions I have seen, it is not statistically significant if the CI includes 1 CI (0.8-1.2) example
There is a question on uworld that is stat significant because the null does not cross 0 CI(1-1.4)

so how do I differentiate between CI crossing 1 vs 0?
Reply With Quote Quick reply to this message



  #2  
Old 06-09-2015
USMLE Forums Newbie
 
Steps History: Not yet
Posts: 2
Threads: 1
Thanked 0 Times in 0 Posts
Reputation: 10
Default

Hi ..

If given CI includes 1, H0 is not rejected which means no statistically significant effect of exposure
Examples
C.I. (0.8 – 2.46) not statistically significant (have same risk)
C.I. (1.22 – 2.45) increase risk (RR=1.77) ---> 1.77-1= 0.77 or 77% more cases
C.I. (0.45 – 0.95) decrease risk (RR= 0.78) ---> 1-0.78= 0.22 or 22% .. so one group has 22% reduction in risk

taken from Kaplan book
hope this will help
Reply With Quote Quick reply to this message



Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the USMLE Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Medical School
Choose "---" if you don't want to tell. AMG for US & Canadian medical schools. IMG for all other medical schools.
USMLE Steps History
What steps finished! Example: 1+CK+CS+3 = Passed Step 1, Step 2 CK, Step 2 CS, and Step 3.

Choose "---" if you don't want to tell.

Favorite USMLE Books
What USMLE books you really think are useful. Leave blank if you don't want to tell.
Location
Where you live. Leave blank if you don't want to tell.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Really Good Question!!! ICUdoc USMLE Step 1 Forum 8 04-18-2014 01:37 PM
Biostats Question shyangel18 USMLE Step 2 CK Forum 13 09-06-2012 05:06 PM
Good Samaritan Law question Casandra USMLE Step 1 Forum 13 06-04-2012 08:38 AM
The Good, the Bad and the Ugly. (A thought on a good USMLE-type question) DocSikorski USMLE Step 1 Forum 1 05-09-2012 10:01 AM
what are some good step 1 question books?? saty_montana USMLE Step 1 Forum 2 08-27-2010 05:55 AM

RSS Feed
Find Us on Facebook
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

USMLE® & other trade marks belong to their respective owners, read full disclaimer
USMLE Forums created under Creative Commons 3.0 License. (2009-2014)