Psychological Transdiagnostic Processes in Mild Traumatic Brain Injury Recovery: A Scoping Review.

Objectives: To examine the extent to which psychological transdiagnostic processes have been investigated in relation to mild traumatic brain injury (mTBI) recovery outcomes, summarize methodological approaches, and evaluate consistency among transdiagnostic processes and outcome measures.

Data sources: Five databases (Ovid MEDLINE, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, Scopus, and Web of Science) were searched from inception to October 2024. Eleven transdiagnostic processes were identified for inclusion based on a review of existing systematic reviews and meta-analyses establishing transdiagnostic relevance across a range of psychological disorders: attentional bias, avoidance, emotion regulation, flexibility, interpretation bias, intolerance of uncertainty, neuroticism, perfectionism, repetitive negative thinking, self-discrepancy, and shame.

Study selection: Peer-reviewed, empirical studies published in English were included if they involved human participants with mTBI predominantly aged ≥18 years and reported ≥1 association between a transdiagnostic process and an mTBI recovery outcome.

Data extraction: Three reviewers extracted data on study design, sample characteristics, transdiagnostic processes and their associated mTBI outcome measures, and analytical approaches using a standardized extraction form.

Data synthesis: Sixty-seven studies published between 1995 and 2024 were included, yielding 118 transdiagnostic process-outcome associations. Avoidance (29%), flexibility (29%), and interpretation bias (25%) were the most frequently investigated transdiagnostic processes; symptom severity (36%) and disability (18%) were the most frequently reported outcomes. No studies examined associations involving attentional bias, emotion regulation, or perfectionism. Substantial heterogeneity in transdiagnostic processes and outcome measurement was observed. While most studies employed quantitative analysis methods, qualitative approaches uniquely captured less represented transdiagnostic process-outcome associations (eg, intolerance of uncertainty, self-discrepancy, shame).

Conclusions: Although interest in transdiagnostic processes and mTBI recovery is growing, current investigations are centered on a narrow range of psychological constructs. Broader investigation of transdiagnostic processes known to maintain psychopathology and greater methodological consistency are needed.