Study Design, Measurement of Variables & Data Collection for Public Health

Question 1

How do people come up with research questions?

Answer 1

They have ideas about things around them and have questions to answer them

Question 2

What does randomization do?

Answer 2

It limits the selection bias

Question 3

What is a variable?

Answer 3

Something that we can assess in a study. It measures the attributes or characteristics of a study.
-can be a person, place, or thing
Ex: age, weight, height

Question 4

Nominal scales?

Answer 4

Categorical values
-used w/ variables that refer to 2 or more classes, groups, categories, etc.
-attributes are only named; weakest
Ex: 0 Blonde 1 Brunette 3 Redhead; 0 Muslim 2 Catholic 3 Christian; The numbers mean nothing; just for data

Question 5

Ordinal scales?

Answer 5

Ordinal variables
-values assigned based on rank. Think of a race or competition
-attributes can be ordered
Ex: Ellen 1, Tom 2, Kristen 3 means that Ellen is ahead or was first

Question 6

Interval scales?

Answer 6

Continuous variables
-equal difference between variables have equal meaning
-values are measured on a metric
-distance is meaningful
Ex: yr. of birth: 1992, 1997, 2002 all have the same difference between them (5 years)
-most psychosocial states are measured this way

Question 7

Ratio scales?

Answer 7

Continuous variables; the same as interval scales

• absolute zero
• keeps count

Question 8

Likert Scale?

Answer 8

Range of answers that are equal distant from each other
-developed by Rensis Likert
-used to assess attitudes, beliefs, behaviors, etc.
Ex: Strongly Disagree to Strongly Agree

Question 9

What is the logic scheme for research studies?

Answer 9

• Observation
• Research question
• Study Design
• Data collection
• Data analysis & results

Question 10

What is AD de Groot (Empirical Cycle)?

Answer 10

a cycle

-Observation to Induction to Deduction to Testing to Evaluation. Over and over

Question 11

What is empirical research?

Answer 11

a way of gaining knowledge. It answers a research question

Ex: Does sex education in elementary schools lead to less sexual risk taking in adolescence among both men and women?

Question 12

Characteristics of research questions?

Answer 12

indicate the possibility of for testing

• associations between 2 or more variables
• associations between exposure and disease states
• associations between independent/dependent variables

Question 13

What is a subjective question?

Answer 13

non-researchable; based on what individuals may know
-aim to measure feelings, attitudes, and perceptions of something
Ex: Should sex ed. be provided in elementary schools?

Question 14

Criteria for research questions?

Answer 14

• expresses the relation between 2 or more variables
• implies that there must be a manner to test this relation
• should be able to test the variables
• asked in a question format
• specifies the population format

Question 15

Types of research questions?

Answer 15

• Cause and effect (what is the effect of X on Y?)
• Association (is X related to Y?)
• Differences (does Y differ among groups of X?)

Question 16

Does causation imply association? Vice-versa?

Answer 16

No

Question 17

Variables can be measured. T or F?

Answer 17

True

• age can be measured in years or in categories
• gender can be male, female, etc.
• depression can be on a scale of the BDI

Question 18

How do variables have value?

Answer 18

The value can diffrentiate based on what the variable is towards. Ex: 100 on an exam doesn’t have the same meaning as 100 on a thermometer
-Values are important bc it gives a proper way for things to be measured
Ex; Anxiety level of a person
Ex: iTune single download chart
Ex: Race/ethnicity

Question 19

What are continuous variables?

Answer 19

variables that continue counting…
Ex: age; a person could be 25 yrs, 10 months, 2 days, etc
Ex: how many vaccination doses have you had?
-distance is equally spaced; space has meaning

Question 20

What are categorical variables?

Answer 20

-variables can be put in categories
Ex: 0 brunette/1 redhead/2 blonde
-space doesn’t have meaning

Question 21

What are ordinal (rank) variables?

Answer 21

Same as categorical variables, but w/ a difference.
Ex: Canada 1, USA 2, Russia 3 indicates a rank
-space doesn’t have meaning

Question 22

Scales?

Answer 22

A set of numbers/values meant to represent the values of a variable
Ex: a ruler that measures height, length, width

Question 23

Types of scales?

Answer 23

• Nominal
• Ordinal
• Interval
• Ratio

Question 24

What converts data into information?

Answer 24

Statistics

Question 25

Methods for data collection? (Interpretive)

Answer 25

• interviewing
• group discussions
• open/closed ended questions
• direct observation
• scales and measures

Question 26

How can direct observation be overt?

Answer 26

when the subject or individuals in the environment know the purpose of the observation; open

Question 27

How can direct observation be covert?

Answer 27

when the subject and individuals are unaware of the purpose; closed

Question 28

What are closed ended questions?

Answer 28

Asks for a simple response

• yes/no
• multiple choice
• likert scale

Question 29

Multiple linear regression?

Answer 29

if the Y/D/outcome/criterion is is continuous

Question 30

Logistic regression?

Answer 30

if the outcome is categorical

Question 31

What are the 2 main types of designs?

Answer 31

• Observational

- Experimental

Question 32

Types of observational studies?

Answer 32

• Case-control
• Cohort
• Cross sectional

Question 33

Types of experimental studies?

Answer 33

-RCT (Randomized control trial)

Question 34

Cross sectional study?

Answer 34

observational study that involves data collection from a pop., at one specific point in time; asks of disease status and exposure
Ex: the gross annual income for each of 1000 randomly chosen households in New York City for the year 2000

Question 35

Cohort study? (panel study)

Answer 35

observational study that is longitudinal and involves data collection from a group of people over many points in time to examine factors related to an outcome; evaluates exposure over time and looks at disease status later
Ex: students at HHS from 2010-2015 who may have gotten sick from eating the cafeteria lunch. record the outcomes, meet w/ them occasionally, etc.

Question 36

Case-control study?

Answer 36

observational study in which two existing groups differing in outcome (disease) are identified and compared on the basis of some supposed causal attribute (exposure)
Ex: one group w/ heart palpitations will have ectasy to experiment and a control group also w/o heart palpitations will also be effected w/ ectasy

Question 37

RCT?

Answer 37

directly comparing 1 treatment w/ another to determine which would have greater benefit

Question 38

Observational studies can be done by?

Answer 38

-surveys
-electronic charts
-other approaches*

Question 39

Experimental studies can be done by?

Answer 39

-clinical trial
-other systematic ways of data collection

Question 39

Comparison may be done in both observational and experimental studies
T or F?

Answer 39

True