Biostatistics #11 - Type of study (4 question) - 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 06-05-2011
bebix's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,357
Threads: 194
Thanked 3,259 Times in 881 Posts
Reputation: 3269
Stats Biostatistics #11 - Type of study (4 question)

1.-Fifteen hundred adult males working for Lockheed Aircraft were initially examined in 1951 and were classified screened for coronary artery disease. Every 3 years they have been examined for new cases of the disease; attack rates in different subgroups have been computed annually.

This study is an example of a:

a. cross-sectional study
b. case-control study
c. retrospective cohort study
d. clinical trial
e. prospective cohort study

2.-A random sample of middle-aged sedentary women was selected from four census tracts, and each subject was examined for evidence of osteoporosis.
Those found to have the disease were referred to their primary medical provider. All others were randomly assigned to either an exercise group, which followed a 2-year 3 day a week program of systematic exercise, or a control group, which had no exercise program, but met 3 days per week to play cards and do crafts. Both groups were observed semi-annually for incidence of osteoporosis.


This study is an example of a:

a. cross-sectional study
b. case-control study
c. retrospective cohort study
d. clinical trial
e. prospective cohort study

3.-Questionnaires were mailed to ever 10th person listed in the city telephone directory. Each person was asked to provide his or her age, sex and smoking habits and to describe the presence of any respiratory symptoms during the preceding 7 days. Over 90% of the questionnaires were completed and returned.

This study is an example of a:

a. cross-sectional study
b. case-control study
c. retrospective cohort study
d. clinical trial
e. prospective cohort study

4.-One hundred patients with infectious hepatitis and 100 matched neighborhood well controls were questioned regarding a history of eating raw clams or oysters within the preceding three months.

This study is an example of a:

a. cross-sectional study
b. case-control study
c. retrospective cohort study
d. clinical trial
e. prospective cohort study
Reply With Quote Quick reply to this message
The above post was thanked by:
carisma_200x (06-06-2011), docoftheworld (06-06-2011), pass7 (06-05-2011), singapur_md (06-05-2011), struggle (06-06-2011)



  #2  
Old 06-05-2011
USMLE Forums Scout
 
Steps History: Not yet
Posts: 21
Threads: 1
Thanked 16 Times in 13 Posts
Reputation: 26
Default

1) c
2) d
3) a
4) b
Reply With Quote Quick reply to this message
The above post was thanked by:
bebix (06-05-2011)
  #3  
Old 06-05-2011
pass7's Avatar
USMLE Forums Guru
 
Steps History: 1+CK+CS+3
Posts: 406
Threads: 30
Thanked 140 Times in 108 Posts
Reputation: 150
Default

1. C
2. D
3. A
4. B
Reply With Quote Quick reply to this message
The above post was thanked by:
bebix (06-05-2011)
  #4  
Old 06-06-2011
USMLE Forums Newbie
 
Steps History: Step 1 Only
Posts: 8
Threads: 0
Thanked 4 Times in 4 Posts
Reputation: 14
Default

1) E
2) B
3) A
4) C

????
Reply With Quote Quick reply to this message
The above post was thanked by:
bebix (06-06-2011)
  #5  
Old 06-06-2011
docoftheworld's Avatar
USMLE Forums Veteran
 
Steps History: 1 + CS
Posts: 204
Threads: 56
Thanked 41 Times in 36 Posts
Reputation: 51
Send a message via Skype™ to docoftheworld
Default

1) E

2) D

3) A

4) B

---------------------

could you PM me the answer
Reply With Quote Quick reply to this message
The above post was thanked by:
bebix (06-06-2011)
  #6  
Old 06-06-2011
USMLE Forums Guru
 
Steps History: Not yet
Posts: 324
Threads: 70
Thanked 236 Times in 143 Posts
Reputation: 246
Default

Quote:
Originally Posted by bebix View Post
1.-fifteen hundred adult males working for lockheed aircraft were initially examined in 1951 and were classified screened for coronary artery disease. Every 3 years they have been examined for new cases of the disease; attack rates in different subgroups have been computed annually.

this study is an example of a:

A. Cross-sectional study
b. Case-control study
c. Retrospective cohort study
d. Clinical trial
e. Prospective cohort study

2.-a random sample of middle-aged sedentary women was selected from four census tracts, and each subject was examined for evidence of osteoporosis.
Those found to have the disease were referred to their primary medical provider. All others were randomly assigned to either an exercise group, which followed a 2-year 3 day a week program of systematic exercise, or a control group, which had no exercise program, but met 3 days per week to play cards and do crafts. Both groups were observed semi-annually for incidence of osteoporosis.


this study is an example of a:

A. Cross-sectional study
b. Case-control study
c. Retrospective cohort study
d. Clinical trial
e. Prospective cohort study

3.-questionnaires were mailed to ever 10th person listed in the city telephone directory. Each person was asked to provide his or her age, sex and smoking habits and to describe the presence of any respiratory symptoms during the preceding 7 days. Over 90% of the questionnaires were completed and returned.

this study is an example of a:

A. Cross-sectional study
b. Case-control study
c. Retrospective cohort study
d. Clinical trial
e. Prospective cohort study

4.-one hundred patients with infectious hepatitis and 100 matched neighborhood well controls were questioned regarding a history of eating raw clams or oysters within the preceding three months.

this study is an example of a:

A. Cross-sectional study
b. Case-control study
c. Retrospective cohort study
d. Clinical trial
e. Prospective cohort study
1.e
2.e
3.a
4.b.
Reply With Quote Quick reply to this message
The above post was thanked by:
bebix (06-06-2011)
  #7  
Old 06-06-2011
Dr_Laura's Avatar
USMLE Forums Guru
 
Steps History: 1+CK+CS
Posts: 499
Threads: 85
Thanked 529 Times in 222 Posts
Reputation: 539
Default

1 e
2 e
3 a
4 b

TELLLL USSSS!!! :sorry:
__________________
YouTube:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Facebook:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Reply With Quote Quick reply to this message
The above post was thanked by:
bebix (06-06-2011)
  #8  
Old 06-06-2011
USMLE Forums Scout
 
Steps History: 1+CK+CS
Posts: 37
Threads: 4
Thanked 35 Times in 14 Posts
Reputation: 45
Default

1. E
2. D
3. A
4. B

waiting for the right answers

and thank you for these great Qs. we really need to practice biostats
Reply With Quote Quick reply to this message
The above post was thanked by:
bebix (06-06-2011)
  #9  
Old 06-06-2011
USMLE Forums Scout
 
Steps History: Not yet
Posts: 45
Threads: 0
Thanked 31 Times in 21 Posts
Reputation: 41
Question

1) e
2) b
3) a
4) b
Reply With Quote Quick reply to this message
The above post was thanked by:
bebix (06-06-2011)
  #10  
Old 06-06-2011
bebix's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,357
Threads: 194
Thanked 3,259 Times in 881 Posts
Reputation: 3269
Correct Answer correct answer

1.-Fifteen hundred adult males working for Lockheed Aircraft were initially examined in 1951 and were classified screened for coronary artery disease. Every 3 years they have been examined for new cases of the disease; attack rates in different subgroups have been computed annually.

e. prospective cohort study

2.-A random sample of middle-aged sedentary women was selected from four census tracts, and each subject was examined for evidence of osteoporosis.
Those found to have the disease were referred to their primary medical provider. All others were randomly assigned to either an exercise group, which followed a 2-year 3 day a week program of systematic exercise, or a control group, which had no exercise program, but met 3 days per week to play cards and do crafts. Both groups were observed semi-annually for incidence of osteoporosis.


d. clinical trial

3.-Questionnaires were mailed to ever 10th person listed in the city telephone directory. Each person was asked to provide his or her age, sex and smoking habits and to describe the presence of any respiratory symptoms during the preceding 7 days. Over 90% of the questionnaires were completed and returned.

a. cross-sectional study

4.-One hundred patients with infectious hepatitis and 100 matched neighborhood well controls were questioned regarding a history of eating raw clams or oysters within the preceding three months.

b. case-control study
Reply With Quote Quick reply to this message
The above post was thanked by:
carisma_200x (06-06-2011), drortho (11-23-2011), giuliane (06-06-2011), pass7 (06-06-2011), Rookie (07-01-2012), rulz (10-06-2011)
  #11  
Old 06-13-2011
USMLE Forums Addict
 
Steps History: 1 + CS
Posts: 159
Threads: 52
Thanked 71 Times in 32 Posts
Reputation: 81
Default ?

can u explain how 2 is clinical trial?
Reply With Quote Quick reply to this message
  #12  
Old 06-13-2011
bebix's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,357
Threads: 194
Thanked 3,259 Times in 881 Posts
Reputation: 3269
Default

Quote:
Originally Posted by meka View Post
can u explain how 2 is clinical trial?
2.-A random sample of middle-aged sedentary women was selected from four census tracts, and each subject was examined for evidence of osteoporosis.
Those found to have the disease were referred to their primary medical provider. All others were randomly assigned to either an exercise group, which followed a 2-year 3 day a week program of systematic exercise, or a control group, which had no exercise program, but met 3 days per week to play cards and do crafts. Both groups were observed semi-annually for incidence of osteoporosis.

d. clinical trial

So, in a random fashion, all subject without osteoporosis were randomized to either "exercise group" or "no exercise group".
Reply With Quote Quick reply to this message
The above post was thanked by:
meka (06-13-2011)
  #13  
Old 06-13-2011
USMLE Forums Newbie
 
Steps History: Not yet
Posts: 2
Threads: 1
Thanked 1 Time in 1 Post
Reputation: 11
Smile

2 - in case-control studies, patients are not randomized into groups. there's a criteria like "the ones with disease" (case) and "the ones without the disease" (control)

in this question, all women are pretty much in the same condition (healthy) and are randomized into groups
Reply With Quote Quick reply to this message
The above post was thanked by:
meka (06-13-2011)
  #14  
Old 06-13-2011
USMLE Forums Veteran
 
Steps History: 1 + CS
Posts: 216
Threads: 56
Thanked 116 Times in 56 Posts
Reputation: 116
Default

yup e, d, a, b
Reply With Quote Quick reply to this message
  #15  
Old 06-15-2011
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,175
Threads: 38
Thanked 852 Times in 478 Posts
Reputation: 862
Default

Quote:
Originally Posted by larissaftorres View Post
2 - in case-control studies, patients are not randomized into groups. there's a criteria like "the ones with disease" (case) and "the ones without the disease" (control)

in this question, all women are pretty much in the same condition (healthy) and are randomized into groups
But you are comparing exercise to non exercise group.

I agree wtih Bebix's answer.
Reply With Quote Quick reply to this message






Reply

Tags
Biostatistics-Epidemiology, Step-1-Questions

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
Biostatistics #8 - Type of study 2 bebix USMLE Step 1 Forum 12 11-24-2013 10:22 PM
NBME7- Biostatistics Question Pixie USMLE Step 1 Forum 4 08-25-2011 08:40 PM
Biostatistics #6 - Type of study bebix USMLE Step 1 Forum 9 06-03-2011 07:19 AM
Biostatistics Question: Analyzing these groups harlesmd USMLE Step 1 Forum 15 04-22-2011 07:46 AM
question celiac disease and DM type 1 dezirablize USMLE Step 2 CK Forum 5 08-04-2010 09:33 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)