# Specific Types Of Quantitative Research & Sampling In Quantitative Research.

Suppose you are going to conduct a study utilizing Quantitative Research Design: which type of research would you use,  and which method would you utilize to collect data and select your sample.

Chapter 12

Sampling in Quantitative Research

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Question

Tell whether the following statement is true or false:

The aggregate of cases in which a researcher is interested is called a sample.

False

The aggregate of cases in which a researcher is interested is called a population. A sample is selection of a portion of the population to represent the entire population.

Basic Sampling Concepts in Quantitative Studies

Population: the aggregate of cases in which a researcher is interested

Sampling: selection of a portion of the population (a sample) to represent the entire population

Element: basic population unit about which information is collected

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Eligibility Criteria

• Establish population characteristics
• Determine participation in study
• Maximize construct validity
• Inclusion
• Exclusion

Question

Tell whether the following statement is true or false:

Researchers usually sample from the target population.

False

Researchers usually sample from the accessible population but should identify the target population to which they want to generalize their results.

Basic Sampling Concepts in Quantitative Studies

Representative sample

A sample whose key characteristics closely approximate those of the population

Sampling bias

The systematic over- or underrepresentation of segments of the population on key variables

Question

Tell whether the following statement is true or false:

Probability sampling involves random selection of elements.

True

Probability sampling involves random selection of elements.

Basic Sampling Concepts in Quantitative Studies (cont.)

Probability sampling

Involves random selection of elements

Nonprobability sampling

Does not involve selection of elements at random

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Nonprobability Sampling

• Convenience sampling
• Snowball sampling
• Quota sampling
• Consecutive sampling
• Purposive sampling

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Probability Sampling

• Simple random sampling
• Stratified random sampling
• Multistage sampling
• Cluster sampling
• Systematic sampling

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Power Analysis

• Estimate sample size
• Large samples preferred to small samples

Chapter 11

Specific Types of
Quantitative Research

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Question

Tell whether the following statement is true or false:

Phase I clinical trials involve seeking opportunities for refinements and preliminary evidence of efficacy.

False

Phase II clinical trials involve seeking opportunities for refinements and preliminary evidence of efficacy. Phase I features of the intervention that are finalized.

Clinical Trials

• Effectiveness of clinical interventions
• Phase I
• Phase II
• Phase III
• Phase IV

Sequential Clinical Trial

• Data from paired “mini-experiments”
• Continuously analyzed
• Preference measures
• Stopping rules

Question

Tell whether the following statement is true or false:

Practical clinical trials aim to reduce the gap between efficacy and effectiveness studies.

False

Practical clinical trials are designed to provide information to clinical decision makers.

Practical Clinical Trials

• Also called pragmatic clinical trials
• Provide information to clinical decision makers

Evaluation Research

• Effectiveness of a program, policy, procedure
• Assist decision makers

Question

What is the purpose of an outcome analysis?

Describes the status of some condition after the introduction of a program

Tests whether a program causes net impacts

Describes the process by which a program gets implemented and functions in practice

Assesses whether the monetary costs of a program are outweighed by benefits

A

Outcome analysis describes the status of some condition after the introduction of a program.

Impact analysis tests whether a program causes net impacts.

Process analysis describes the process by which a program gets implemented and functions in practice.

Cost analysis assesses whether the monetary costs of a program are outweighed by benefits.

Various Analyses

• Process or implementation
• Outcome
• Impact
• Cost or economic
• Cost–benefit analysis
• Cost-effectiveness analysis
• Cost-utility analysis

Question

Tell whether the following statement is true or false:

Outcome research examines the quality and effectiveness of health care and nursing services.

True

Outcome research examines the quality and effectiveness of health care and nursing services.

Outcome Research

• Quality and effectiveness of health care and nursing services
• Health care quality
• Structure
• Process
• Client risk factors
• Outcomes

Survey Research

• People’s characteristics, behaviors, and intentions by asking them to answer questions
• Personal interviews
• Telephone interviews
• Questionnaires

Secondary Analysis

• Researchers analyze previously collected data.
• Economical
• Difficult to identify appropriate existing data base

Needs Assessment

• Needs of group or community
• Three main needs
• Key informant
• Survey
• Indicators approach

Question

Tell whether the following statement is true or false:

The Delphi technique is a method of problem solving in which one round of questionnaires are sent to a panel of experts.

False

The Delphi technique is a method of problem solving in which several rounds of questionnaires are sent to a panel of experts, not one round.

Delphi Technique

• Problem solving
• Several rounds of questionnaires

Replication Studies

• Identical
• Virtual
• Systematic extension replication