Biomedical subjects

Michael D Franzen

Publications and source records attributed to Michael D Franzen.

4 recordsLinked to original sources

PubMed2005

Effects of mild traumatic brain injury cannot be differentiated from substance abuse.

PRIMARY OBJECTIVE: Patients involved in litigation relating to mild traumatic brain injury (MTBI) typically undergo a forensic neuropsychological evaluation. However, if cognitive problems are identified, it is difficult to know whether these are related to the MTBI or other factors such as pre- and/or post-injury substance abuse. The purpose of this study was to compare the neuropsychological test performances of 73 patients with acute, uncomplicated MTBIs to a sample of 73 patients from an inpatient substance abuse programme. METHODS AND PROCEDURES: Patients were perfectly matched on age, education and gender. Ten cognitive measures were used that included the Trail Making Test (TMT) and selected sub-tests from the Wechsler Memory Scale-Revised. MAIN OUTCOMES AND RESULTS: Patients with MTBI demonstrated poorer performances on Digits Backwards (p < 0.028) and TMTA (p < 0.032). There were no significant differences between the two groups on the remaining cognitive measures. The clinical usefulness of these measures to differentiate between the groups, using discriminant function analysis, was very poor. CONCLUSIONS: Patients with uncomplicated MTBIs could not be reliably differentiated from patients with substance abuse problems on these measures of concentration, memory and processing speed.

Adolescent↗

PubMed2005

Interpreting the trail making test following traumatic brain injury: comparison of traditional time scores and derived indices.

The purpose of this study was to examine the clinical application of traditional time scores and various derived indices from the Trail Making Test (TMT) in a sample of 571 patients with acute traumatic brain injury (TBI). Participants were classified into four injury severity groups. A clear linear relation between injury severity and TMT performance was demonstrated, with the more severely brain injured patients performing more poorly on most measures. Hierarchical logistic regression analysis of TMT time scores across binary extreme groups based on injury severity resulted in high classification rates for patients with very mild TBI (93.0% correctly classified) and low classification rates for patients with moderate to severe TBI (50.0% correctly classified). However, TMT derived indices did not provide a unique contribution to test interpretation beyond what is already available from Part A and B separately.

Adult↗

PubMed2003

Presence of post-concussion syndrome symptoms in patients with chronic pain vs mild traumatic brain injury.

PRIMARY OBJECTIVE: Post-concussion syndrome (PCS) is a controversial diagnosis, in part because many symptoms may be present in other conditions, such as chronic pain (CP). However, direct comparisons between people with CP and mild traumatic brain injury (MTBI) are limited. The purpose of this study was to compare people with CP and MTBI on a measure of PCS symptoms. DESIGN: Group comparison between patients with CP and MTBI on the Rivermead Post-Concussion Questionnaire (RPCQ). METHODS: Sixty-three patients with CP and 32 with MTBI were evaluated at the authors' institutions. Patients completed the RPCQ as part of their initial evaluation. RESULTS: No group differences were found for total RPCQ scores. There were some differences in the proportion of patients endorsing specific symptoms. However, most people with CP endorsed symptoms consistent with PCS. CONCLUSIONS: PCS symptoms are not unique to MTBI, and may be seen in conditions such as CP.

Adult↗

PubMed2002

Detecting exaggeration and malingering with the trail making test.

The purpose of this study was to examine whether unusual performance on the Trail Making Test could be indicative of deliberate exaggeration. Participants were 571 patients seen as part of a hospital trauma service who had acute traumatic brain injuries, and 228 patients involved in head injury litigation. As expected, the hospital patients with more severe traumatic brain injuries performed more poorly than the patients with less severe brain injuries on Trails A and Trails B. Cutoff score tables were developed for the patients with acute traumatic brain injuries for the total sample and by injury severity groups. Scores falling at or below the 5th percentile were considered suspicious for possible exaggeration. The performances of the head injury litigants who exaggerated on at least one well-validated symptom validity test were compared to these cutoffs. Very high positive predictive values for individuals with very mild head injuries on Trails A and B were identified (i.e., both 100%); lower positive predictive values were obtained for individuals with more severe head injuries (55.6-60%). The negative predictive values were only moderate (range=66.4-78.2%), and the sensitivity was very low (range = 7.1-18.5%) for all groups. Scores that fall in the range of possible biased responding should be considered "red flags" for the clinician because they likely do not make biological or psychometric sense. However, the sensitivity of the test for deliberate exaggeration is very low, so clinicians who rely on this test in isolation to identify deliberately poor performance will fail to identify the vast majority of cases.

Adult↗