Does the cause of the mild traumatic brain injury affect the expectation of persistent postconcussion symptoms and psychological trauma?

ABSTRACT

Introduction: A controlled experiment of the effect of injury cause on expectations of outcome from mild traumatic brain injury (TBI) was conducted. Method: Ninety-three participants were randomly assigned to one of four conditions. The participants read a vignette that described a mild TBI (with fixed injury parameters) from a different cause (sport, domestic assault, fall, or motor vehicle accident). The effect of the manipulation on expectations of persistent postconcussion symptoms and psychological trauma was assessed with standard measures and a novel “threat-to-life” measure. Results: The Kruskal–Wallis H test for group differences revealed a significant but selective effect of group on symptom and trauma outcomes (ŋ²s ≥ .10; large effects). Post hoc pairwise tests showed that, in most cases, there was an expectation of a worse outcome following mild TBI from a domestic assault than from the other causes (small-to-medium effects). Conclusion: Expectations were selectively altered by an experimental manipulation of injury cause. Given that expectations of outcome are known to affect mild TBI prognosis, the findings suggest the need for greater attention to injury cause.

KEYWORDS:

• Concussion
• Mild brain injury
• Mild traumatic brain injury
• Postconcussion symptoms
• Posttrauma response
• Simulation
• Traumatic brain injury

Acknowledgments

The authors acknowledge the contribution of Shannon L. Edmed to the design and conception of this project, including development of the vignettes and methodology. Sherrie-Anne Kaye assisted with the preparation of the final manuscript. Preliminary data from this project were presented at the 21st annual conference of the Australian Psychological Society College of Clinical Neuropsychology, 19 – 21 November 2015, Shoal Bay, New South Wales, Australia.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

¹ This is a limited control of important clinical injury parameters only.

² A fifth condition, assault by a stranger, was also administered and is separately reported. In this study the term domestic assault is used to describe an injury caused by the protagonists’ “partner” (intimate partner assault).

³ These significant overall group differences were also examined in a series of exploratory analyses to control for age (analysis of covariance). Age was not a significant covariate in any of the analyses (all ps > .141). The overall group differences were still significant after controlling for age (all ps < .025). This was determined using a conservative alpha because of some breaches of normality (Keppel & Wickens, 2004).

Additional information

Funding

This work was supported by the The Queensland University of Technology University Human Research Ethics Committee (QUT HREC) [approval number 1200000150]; funding for the prize awarded in this project was provided by the School of Psychology and Counselling, Queensland University of Technology (QUT).