The degree to which changes in the dependent variable are due to the manipulation of the independent variable describes which concept?

The degree to which changes in the dependent variable are due to the manipulation of the independent variable describes which concept?

• A. Internal validity
• B. External validity
• C. Construct validity
• D. Reliability

Answer: (A)

Internal validity is about whether the observed change in the dependent variable can be genuinely attributed to the manipulation of the independent variable, rather than to other extraneous factors. It focuses on how well the experiment controls for confounds, ensuring that the IV is the cause of the DV change. Techniques that boost internal validity include random assignment, control groups, blinding, and standardized procedures to minimize placebo effects, maturation, measurement error, and other confounding influences. External validity, by contrast, is about whether findings generalize beyond the specific study setting, population, and procedures. Construct validity asks whether the measures and manipulations actually capture the intended theoretical constructs. Reliability concerns the consistency of measurements across time, items, or raters. For example, if a mood change is observed after a treatment, high internal validity means we can be confident that the change is due to the treatment itself, not to participants’ expectations or other uncontrolled factors.

Internal validity is about whether the observed change in the dependent variable can be genuinely attributed to the manipulation of the independent variable, rather than to other extraneous factors. It focuses on how well the experiment controls for confounds, ensuring that the IV is the cause of the DV change. Techniques that boost internal validity include random assignment, control groups, blinding, and standardized procedures to minimize placebo effects, maturation, measurement error, and other confounding influences.

External validity, by contrast, is about whether findings generalize beyond the specific study setting, population, and procedures. Construct validity asks whether the measures and manipulations actually capture the intended theoretical constructs. Reliability concerns the consistency of measurements across time, items, or raters. For example, if a mood change is observed after a treatment, high internal validity means we can be confident that the change is due to the treatment itself, not to participants’ expectations or other uncontrolled factors.