What is STAR-C
STAR-C — the Symptom-Targeted Approach to Rehabilitation for Concussion — is a brief, strategy-based cognitive rehabilitation protocol for adults with a history of mild traumatic brain injury (mTBI) and persistent everyday cognitive complaints. The protocol was developed and pilot-tested over a previous three-year pragmatic trial; the current RCT moves it into a controlled comparison and tests delivery by telehealth.
Therapy is symptom-focused: the goal is to reduce the cognitive challenges patients report in everyday life. Targets are negotiated collaboratively between clinician and patient and scaled using Goal Attainment Scaling.
Trial design
The current RCT is a three-arm trial across two military treatment facilities:
- In-person STAR-C
- Telehealth STAR-C
- Wait-list control
Target enrollment is 222 patients. Outcomes are assessed immediately post-treatment and at one- and three-month follow-up. Recruitment began September 2025, with primary completion estimated December 2026 and study completion estimated August 2028.
Specific aims
The protocol specifies four aims:
Aim 1 (primary). Evaluate the effectiveness of STAR-C. The hypothesis is that both in-person and telehealth STAR-C will lead to a greater decrease in everyday cognitive complaints (measured on the C4) compared to the wait-list control.
Aim 2 (secondary). Evaluate maintenance of treatment effects using a practice-based evidence approach — what proportion of treatment effects on the C4 and Goal Attainment Scaling are maintained at three-month follow-up, for each arm.
Aim 3 (exploratory). Explore factors associated with heterogeneity in treatment response — what prevented some participants from achieving or maintaining a ≥2-point improvement on the C4, and what contributed when participants did meet or exceed their GAS targets.
Aim 4 (implementation). Use stakeholder input from clinicians, administrators, and patients — through capacity assessment and after-action review — to generate an implementation package for clinics interested in adopting STAR-C. Clinician ratings of acceptability, appropriateness, and feasibility are captured using the AIM/IAM/FIM measures.
Theoretical basis
STAR-C draws on four converging frameworks:
- Rehabilitation Treatment Specification System (RTSS). A framework for naming the active ingredients of a rehabilitation treatment — what the clinician does, why, and how it is intended to produce change.
- Neuroplasticity principles. Specifically the use of high-dose, spaced practice of tasks that are personally meaningful to the patient, rather than generic cognitive exercises.
- Health psychology. An explicit focus on self-efficacy and motivation as drivers of behavior change, not only on skill acquisition.
- Community-based participatory research. The protocol was co-designed with the clinicians who would deliver it, making implementation feasibility a design constraint from the start.
What we measure
The primary patient-reported outcome is the C4 questionnaire — Common Cognitive Complaints after Concussion — a 22-item activity-based self-report tool used both at intake (to identify treatment targets) and at follow-up (to measure change in everyday cognitive complaints).
Individualized treatment targets are tracked using Goal Attainment Scaling, which scales each target along a five-point gradient and allows progress to be quantified across participants with different specific goals.
Implementation outcomes (Aim 4) use validated measures of clinician-rated acceptability, appropriateness, and feasibility — the AIM, IAM, and FIM scales.
Assessment battery
The full assessment battery spans regulatory instruments, primary outcome measures, patient characteristics, and implementation measures — administered across six timepoints from screening through three-month follow-up. See the Schedule of Events in Materials for the full grid.
Primary outcomes · Aim 1
- C4 Common Concussive Cognitive Complaints — primary patient-reported outcome
- PROMIS General health-related quality of life
- GAS Goal Attainment Scaling — individualized treatment target attainment
Patient characteristics · Aim 2
- Demographics Baseline
- OSU-TBI-ID Ohio State University TBI Identification Method — TBI history
- TBI history Injury history, updated for changes at each timepoint
- Treatment history Prior TBI and behavioral health care
- Current treatment Pharmacological and non-pharmacological, updated per visit
- Computer games Cognitive-training exposure, updated per visit
- WRAT-5 Word Reading Estimated premorbid functioning
- NSI Neurobehavioral Symptom Inventory
- SESx Self Efficacy for Symptom Management
- PCL-5 PTSD Checklist
- PHQ-8 Patient Health Questionnaire — depression
- ESS Epworth Sleepiness Scale
- NIH Toolbox Cognition Objective cognitive battery
- IOP-29 & IOP-M Inventory of Problems — symptom validity
- TOMM Test of Memory Malingering — performance validity
Implementation & qualitative · Aim 3
- Patient interview Semi-structured, post-treatment
- Stakeholder interview Clinicians and administrators
- AIM / IAM / FIM Clinician-rated acceptability, appropriateness, feasibility
Regulatory
- Consent Informed Consent and HIPAA Authorization at screening
- Randomization At baseline (and again post-waitlist for control arm)
Origins of the protocol
The STAR-C protocol was developed and pilot-tested in a prior three-year pragmatic clinical trial with U.S. service members and veterans. That feasibility work — describing the development, theoretical basis, and pilot outcomes of the intervention — is the published precursor to the current RCT (see Publications). In the pilot, treatment fidelity exceeded 95%; participants and clinicians rated the protocol as acceptable, feasible, and appropriate; and most participants attained and maintained their treatment targets. The authors concluded that efficacy should be tested in a controlled design — which is the current trial.