Validity Flashcards
Statistical conclusion validity
(were stats appropriate?)
Validity of inferences about the correlation (covariation) between treatment and outcome.
- Ensure adequate sample size for sufficient statistical power.
- Apply appropriate statistical techniques and correct for multiple testing.
- Control for random error and use reliable measurement tools
Internal validity
(did A cause B?)
Validity of inferences about whether observed covariation between A (presumed treatment) and B (the presumed outcome) reflects a causal relationship from A to B as those variables were manipulated or measured.
Randomization!!!
- Use randomization to assign participants to groups.
- Implement control groups and use blinding.
- Employ a pretest-posttest design.
- Ensure consistent treatment administration.
External validity
(can lessons be extended beyond the lab?)
Validity of inferences about whether the cause-effects relationship holds over variation in persons, settings, treatment variables, and measurement variables.
Generalizability!!!! and replicate!!!!
- Use random sampling to select participants.
- Replicate studies in different settings and with different populations.
- Test the intervention across various conditions.
Construct validity
(what is A?)
Validity of inferences about higher-order constructs that represent sample particulars.
- Clearly define and operationalize constructs.
- Use multiple methods and measures to assess constructs.
- Validate the measurement tools with pilot studies.
Ecological validity
(does the lab context mirror the real world?):
Ambiguous temporal precedence
Internal validity
A causes B? or vice versa (poor sleep vs stress).
Longitudinal or time-series design, and include pre and post-test
Selection
Internal validity
differences in respondent characteristics ( young vs. old)
Random assignment
History
Internal Validity
concurrent events (political events or laws)
Use a control group to compare the effect of external events on both the treatment and control groups.
Maturation
Internal validity
natural changes (older and aging)
Shorten the time span of the study
Regression
Internal validity
extreme scores reverting to mean (high stress ppl, lower level report)
Use repeated measures and include a wide range of participants to reduce regression to the mean effects.
Attrition
Internal validity
systematically drop out (a demanding treatment group)
Implement strategies to maintain participant engagement, monitor reasons for dropouts, and use intention-to-treat analysis
T-test
Testing
Internal validity
test exposure (2nd test with familiarity)
Employ alternative forms of the test or counterbalance the test forms to reduce the impact of repeated testing
Instrumentation
Internal validity
measure/condition changes over time (change in surveys)
Ensure consistency in measurement tools and procedures throughout the study, and calibrate instruments if necessary.
Additive and interactive effects
Internal validity
combined or dependent multiple threats (history + maturation)
Design the study to isolate variables and use statistical controls to account for potential interactions and additive effects.
Interaction of causal relationships with unit
External validity
variability with different unit types (effective in adults NOT in children)
Use random sampling to select participants and replicate the study across different populations.
Interaction of causal relationships over treatment variations
External validity
variability with different treatments (effects of different dosages)
Vary the levels of the treatment and replicate the study with different treatment protocols.
Interaction of causal relationships with outcomes
External validity
variability with different outcome observations (improved mood but not cognitive function from a treatment)
Measure multiple outcomes and use different methods to assess the outcomes to ensure generalizability.
Interaction of causal relationships with settings
External validity
variability in different settings (therapy effective in clinical settings but not at home)
Conduct the study in various settings or replicate the study in different environments to test for consistency.
Context-dependent mediation
External validity
mediator variability in different contexts (social support mediating stress reduction only in community setting)
Explore the mediating effects in different contexts and include diverse contexts in the study design to assess the robustness of the mediating effect.
Inadequate explication of constructs
Construct Validity
poor construct definition lead to incorrect inferences (vaguely defined well-being in psychological.)
Clearly define constructs and ensure they align with established theories; use a panel of experts for validation.
Construct confounding
Construct validity
failure to describe all relevant constructs (not consider both anxiety and depression in mental health study)
Distinguish the constructs from one another and measure them independently; use confirmatory factor analysis.
Mono-operation bias
Construct Validity
limited operationalization complicating inference (only use self-reports to measure happiness)
Employ multiple measures or observations for the construct to capture its complexity.