This disparate finding - 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 2 CK Forum

USMLE Step 2 CK Forum USMLE Step 2 CK Discussion Forum: Let's talk about anything related to USMLE Step 2 CK exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 08-05-2012
USMLE Forums Master
 
Steps History: 1+CK+CS
Posts: 1,867
Threads: 149
Thanked 2,087 Times in 1,047 Posts
Reputation: 2107
Default This disparate finding

A researcher publishes new results on the efficacy of a procedure using transplanted embryonic cells to correct
a diabetic condition induced in experimental animals by chemical ablation of pancreatic beta cells. At another
institution, a different researcher attempts to reproduce the findings, but cannot. This disparate finding calls into
question the first study's


A. accuracy

B. power

C. reliability

D. sensitivity

E. validity
Reply With Quote Quick reply to this message



  #2  
Old 08-05-2012
USMLE Forums Addict
 
Steps History: 1+CK+CS+3
Posts: 151
Threads: 48
Thanked 109 Times in 60 Posts
Reputation: 119
Default

Reliability..C
Reply With Quote Quick reply to this message
  #3  
Old 08-05-2012
USMLE Forums Master
 
Steps History: 1+CK+CS
Posts: 1,867
Threads: 149
Thanked 2,087 Times in 1,047 Posts
Reputation: 2107
Default

Explanation:

The correct answer is C. The reliability of a measurement refers to the ability of other researchers to reproduce
the results.
This can be summarized by noting that reliability = reproducibility.

Random error-reduces precision in a test.
Precision is:
l. The consistency and reproducibility of a test (reliability)
2.The absence of random variation in a test

The accuracy (choice A) of a measurement refers to the "trueness" of the measurement, i.e., how close the
measured value is to the true value
. It is a measure of bias. Just because another researcher could not
reproduce the findings does not necessarily imply that they were inaccurate.
Accuracy is the trueness of test measurements (validity). Systematic error-reduces accuracy in a test.

The power (choice B) of a study is best conceptualized as the probability of rejecting a null hypothesis that is in
fact false
. This is equal to 1 minus the probability of a type II error (1-&beta, since β is the probability of
failing to reject a false null hypothesis. If you increase sample size, you increase power. There is power
in numbers.


The sensitivity (choice D) of a test is a measure of its ability to detect the presence of a disease in those who
truly have the disease.

The validity (choice E) of a measurement is an index of how well the test measures what it purports to measure.
The disparate results obtained by another researcher do not necessarily mean that the results are not valid.

Last edited by Novobiocin; 08-05-2012 at 04:29 PM.
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
finding programs Cocochanel IMG Residency Match Forum 1 08-11-2011 10:07 PM
Lab finding in darker urine usmle2011 USMLE Step 1 Forum 7 08-04-2011 09:54 AM
Diagnose the autopsy finding usmle2011 USMLE Step 1 Forum 7 08-02-2011 04:09 AM
Diagnose the colonoscopic finding usmle2011 USMLE Step 1 Forum 14 08-02-2011 04:06 AM
Which of the following is a likely finding? bebix USMLE Step 1 Forum 10 07-19-2011 04:13 PM

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)