Discuss how longitudinal research in general, and panel research in particular, is arguably the best suited for illuminating cause and effect relationships, using this article as a template.
In particular, while the results of the study examining donated brains of deceased NFL players initially appears to be damning to the NFL in particular, and tackle football in general, I ask students to tailor their discussion toward addressing the need for time-series, longitudinal research, on this important matter. In other words,
o (a) does the current research on CTE, meet all of the criteria for nomothetic causality; and
o (b) if not, how might longitudinal research help meet these criteria?
In essence, based on what you have learned this term, apply the three criteria of nomothetic causality to this study, and discuss whether or not all criteria are met with this research (are there any potential selection effects in operation here?).
Will this longitudinal research change your views on participating in contact sports? Why or why not?
Longitudinal research is the best general design for illuminating causality because it involves collecting data at multiple points in time, which makes it uniquely suited to address the time order and nonspuriousness criteria.
Panel Studies in particular, which track the exact same individuals over an extended period, are ideal. By measuring the "cause" (e.g., years of tackle football exposure) at one point and the "effect" (e.g., development of cognitive impairment or CTE) later, the time order is definitively established. Furthermore, by tracking the same people, panel studies allow researchers to control for many time-stable individual differences (like genetics or childhood IQ), enhancing the ability to establish nonspuriousness.
2. Applying Nomothetic Causality to CTE Brain Studies
The studies examining donated brains of deceased NFL players (often published by organizations like the CTE Center at Boston University) typically involve retrospective post-mortem analysis. While they show a strong association between a history of tackle football and the presence of CTE, they inherently struggle with the core criteria of causality:
Sample Answer
Longitudinal research, particularly panel research, is superior for establishing cause-and-effect relationships because it directly addresses the critical element of time order in causality, which cross-sectional research cannot.
The article on Chronic Traumatic Encephalopathy (CTE) in deceased NFL players, while presenting compelling evidence, highlights the inherent limitations of using non-longitudinal, retrospective data to establish nomothetic causality. This type of research struggles to fully satisfy the three main criteria for a causal relationship.
1. Longitudinal Research and Nomothetic Causality
Nomothetic causality requires three criteria to be met:
Covariation (Correlation): The cause and effect must be associated.
Time Order: The cause must occur before the effect.
Nonspuriousness: The observed relationship cannot be explained by a third, confounding variable.