Chapter 19

Question 2

At least four types of populations considered when preparing to collect data. (4) Broadest to smallest

Answer 2

Target population
Source population (sampling frame)
Sample population
Study population

Question 3

Sampling bias

Answer 3

sample is not representative of the source as a whole

Question 4

Nonrandom sampling bias occurs when

Answer 4

Each individual does not have an equal chance of being selected for the sample population

Question 5

Simple random sampling

Answer 5

Each person has an equal chance of being selected

Question 6

Systemic sampling

Answer 6

sampling starts with a random person and then everyone the nth number after that person is selected

Question 7

Stratified sampling

Answer 7

Simple random samples selected from each of several strata

Question 8

Cluster sampling

Answer 8

An are is divided into geographical clusters and some clusters are selected for inclusion

Question 9

Cross sectional study

Answer 9

researchers analyze data from a population, or a representative subset, at a specific point in time.
aka prevalence study

Question 10

If doing cross sectional study for a large geographic region a

Answer 10

cluster sample will be conducted

Question 11

Convenience population

Answer 11

non-probability based source population selected due to ease of access to those individuals.
Usually schools, workplaces, organizations, or communities.

Question 12

Berkson’s Bias

Answer 12

Occurs when people are sampled from hospital and therefor are more likely to have comorbid conditions

Question 13

Healthy worker bias

Answer 13

can occur when participants are recruited from occupational populations and thus are healthier than the general population

Question 14

Exclusion bias

Answer 14

occurs when exclusion criteria are applied unevenly or if certain subgroups are excluded for reasons that affect the study’s findings.

Question 15

Participation rate is the

Answer 15

Percentage of member of the sample population who are included in the study population

Question 16

Selection bias

Answer 16

occurs when the members of the study population are not representative of the source population

Question 17

nonresponse bias

Answer 17

If the members of a sample population who “agree” to participate are systemically different from those who refused to participate.

Question 18

The strongest cross sectional surveys use

Answer 18

population-based studies that use probability based sampling

Question 19

A Census is

Answer 19

a complete enumeration of a population

Question 20

Case control study

Answer 20

a study that compares the exposure history of those with a disease and people without the disease.
Has inclusion and exclusion criteria

Question 21

Hospitals, specialty clinics, public health offices, disease support groups and advocacy organization are _____ in case-control studies

Answer 21

Helpful
However we must make sure that the participants are not healthier or sicker or more or less socially connected

Question 22

Nested case control study

Answer 22

is a type of observational study where a subset of cases (individuals with the outcome of interest) and controls (individuals without the outcome) are drawn from a “previously established” cohort that has been followed over time.
benefit: No recall bias because participants were followed and data was collected throughout the study not based on participant recall

Question 23

cohort study

Answer 23

used to follow a group of people (a “cohort”) over time to determine how certain exposures or factors influence the development of outcomes, such as diseases or health conditions.

Question 24

Experimental studies focus on

Answer 24

validity of the study and safety of participants

Question 25

Qualitative data sampling

Answer 25

researchers have intense direct contact with a group of key informants

Question 26

Key informant

Answer 26

individuals selected to participate in a qualitative study because they have expertise relevant to the study

Question 27

Purposive sampling

Answer 27

Nonprobabiltiy-based sampling method that recruits participants for a qualitative study based on the special insights they can provide

Question 28

The goal of qualitative studies is to reach

Answer 28

data saturation

Question 29

Data saturation

Answer 29

a time in the research process in which no new information about a particular theory is emerging

Question 30

Vulnerable populations

Answer 30

populations whose members might have limited ability to make an autonomous decision about volunteering to participate in a research study

Question 31

Community involvement

Answer 31

Community buy in often facilitates access to source populations and improves participation rates

Question 32

Resources are wasted when a study recruits

Answer 32

too many or too few participants