Ex-post facto analysis cannot establish causation primarily because:

Ex-post facto analysis cannot establish causation primarily because:

• A. There is a lack of random assignment and experimental control.
• B. It proves causal relationships.
• C. It involves manipulating the independent variable.
• D. It uses longitudinal designs only.

Answer: (A)

Ex-post facto studies study outcomes after they’ve already occurred, without the researcher controlling or randomizing who is exposed to a potential cause. Because there is no random assignment and no experimental control, the groups being compared may differ in many other ways besides the variable of interest. These preexisting differences—confounding variables—can influence the outcome, so any observed association between the presumed cause and effect could be due to these other factors rather than a true causal link. In other words, you can see relationships, but you can’t rule out alternative explanations with the same confidence you can in a randomized experiment. That’s why causation can’t be established from ex-post facto analysis. This design does not manipulate the independent variable, so it doesn’t rely on experimental control to isolate effects. It also isn’t limited to longitudinal designs; it can be cross-sectional or retrospective, which further limits the strength of causal claims.

Ex-post facto studies study outcomes after they’ve already occurred, without the researcher controlling or randomizing who is exposed to a potential cause. Because there is no random assignment and no experimental control, the groups being compared may differ in many other ways besides the variable of interest. These preexisting differences—confounding variables—can influence the outcome, so any observed association between the presumed cause and effect could be due to these other factors rather than a true causal link. In other words, you can see relationships, but you can’t rule out alternative explanations with the same confidence you can in a randomized experiment. That’s why causation can’t be established from ex-post facto analysis.

This design does not manipulate the independent variable, so it doesn’t rely on experimental control to isolate effects. It also isn’t limited to longitudinal designs; it can be cross-sectional or retrospective, which further limits the strength of causal claims.