Research Validity Fundamentals

Vocabulary flashcards covering key terms related to validity, variables, experimental design, and threats to research integrity.

Validity (in research)

The overall truthfulness and accuracy of study results, reflecting whether findings genuinely represent reality.

Independent Variable (IV)

The factor deliberately manipulated by the researcher to observe its effect on the dependent variable.

Dependent Variable (DV)

The outcome or response being measured in a study.

Extraneous Variable

An uncontrolled factor that may influence the dependent variable and threaten study validity.

Requirements for True Experimental Design

Manipulated IV, a control/comparison group, and random assignment of subjects.

Internal Validity

Are the changes in dependent variable caused by independent variable and not by other factors

External Validity

The extent to which study findings can be generalized to other populations, settings, or time periods.

Construct Validity

The clarity and correctness of how IV and DV are defined and linked theoretically and operationally in a study.

Statistical Conclusion Validity

Area statistical methods used appropriately to analyze IV-DV relationship

Internal Validity Casuality Components

1. Temperoal Precedence - Cause comes before effect

2. Covariation of Cause and Effect - change in IV produces change in DV

3. No Plausable Alternatives - Rule out other explanations

Threats to Internal Validity

History
Maturation
Attrition
Testing
Instrumentation
Assignment Bias
Regression Toward the Mean

History Threat

Events outside the study that occur between measurements and influence participant outcomes.

Maturation Threat

Natural physiological or psychological changes in participants over time that affect the DV.

Attrition (Mortality)

Loss of participants during a study, potentially biasing results if dropouts differ systematically from completers.

Testing Threat

Improved performance due to familiarity with assessment tools from prior testing, not the intervention.

Instrumentation Threat

Inconsistencies or changes in measurement tools or procedures that influence study results.

Assignment Bias

Systematic differences between groups arising from non-random allocation of participants.

Regression Toward the Mean

Tendency for extreme scores to move closer to the average on subsequent measurements.

Social Threats to Internal Validity

Difussion/Imitation of Treatment
Compensatory Equalization
Compensatory Rivalry
Resentful Demoralization

Diffusion/Imitation of Treatment

Social interaction spreads intervention

Compensatory Equalization

Researcher treats groups differently

Compensatory Rivalry

Control group works harder

Resentful Demoralization

Control group performs worse out of discouragement

Threats To External Validity

Interation of Treatment and Selection/Setting/History
Reactive Effects of Testing

Threats to Statistical Conclusion Validity

Inappropriate statistical tests.

Violation of assumptions.

Low statistical power.

High error rates.

Poor reliability and validity of tools.

Example that lacks Construct Validity

Isometric knee exercise to improve gait speed