The Moss Attention Rating Scale for traumatic brain injury: further explorations of reliability and sensitivity to change.

Objective: To examine the interrater agreement and responsiveness to change of the Moss Attention Rating Scale (MARS), 22-item version, during acute inpatient rehabilitation after traumatic brain injury (TBI).

Design: Observational study of clinician ratings (physical therapy [PT], occupational therapy [OT], speech-language pathology [SLP], nursing) of each patient's attentional function at 2 points in time, near the time of admission and near the time of discharge from inpatient rehabilitation.

Setting: Dedicated acute inpatient brain injury rehabilitation program.

Participants: Inpatients (N=149) with moderate to severe TBI (58% enrolled in the National Institute on Disability Rehabilitation Research-funded Traumatic Brain Injury Model System); age 16 years or older; receiving OT, PT, SLP, and nursing care on the inpatient TBI rehabilitation unit; and having Rancho Los Amigos Levels of Cognitive Functioning Scale scores of IV (confused/agitated) or higher at enrollment. Patients were excluded if they had premorbid history of attention-deficit hyperactivity disorder, major psychiatric disorder (eg, bipolar), or neurologic impairment (eg, stroke).

Interventions: Not applicable.

Main Outcome Measure: Scores on the MARS (22-item version) and its 3 factor scores.

Results: Intraclass correlations among ratings from PT, OT, and SLP ranged from .69 to .78 at the initial assessment and .67 to .72 at the follow-up assessment. Agreement between nursing and the other disciplines was somewhat lower (at initial assessment, .59-.68; at follow-up, .48-.59), although still substantial. Agreement for 2 of the factor scores (restlessness and/or distractibility, initiation) was similar but agreement for the third factor (consistent and/or sustained attention) was lower (.25-.27). The total MARS scores were highly significantly improved (P<.001) at follow-up compared with initial assessment (mean, 27.6d between ratings; median, 21d; range, 4-125d) for each of the rating disciplines, with change scores ranging from 7.8 points (OT) to 13.1 points (nursing). Factor scores also improved significantly during the same interval. When different occupational therapists provided the initial and follow-up OT ratings, these follow-up ratings were significantly lower, but this pattern was not seen among other rating disciplines.

Conclusions: The 22-item MARS showed good interrater agreement among PT, OT, and SLP and lower but still acceptable agreement between nursing and the other disciplines. Two of the 3 factor scores also showed good agreement. The 22-item total score and all 3 factor scores were highly sensitive to change occurring during inpatient rehabilitation. These results show that the 22-item MARS is a reliable instrument for the observational rating of attentiveness in an acute TBI rehabilitation sample. Lower agreement between nursing and the other disciplines suggests that the less structured environment of the nursing unit compared with therapy sessions reduces interrater agreement. The utility of the factor scores, particularly the least reliable sustained and/or consistent attention factor, requires additional investigation. Further research on construct validity and impact of the use of the MARS on clinical practice are warranted.