Hart , PhD, Moss TBI Model System at
Citation Hart, T. (2008). The
Moss Attention Rating Scale. The Center for Outcome Measurement
in Brain Injury. http://www.tbims.org/
combi/mars ( accessed
The MARS is designed to be completed by clinicians on the basis
of their everyday, routine interaction with the patient; no special
tests or questions are administered. In studies thus far, clinicians
have been asked to think of the 2 or 3 previous days in which they
have treated/ interacted with the patient to form their ratings.
It is not known whether ratings based on a shorter period of time
would show equivalent reliability.
is no manual for administering the MARS because it was developed
to be usable by people from a variety of disciplines and backgrounds
and to provide a simple, rapid assessment of attention behavior.
The only special instruction to raters is not to skip any items,
because doing so prevents calculating a score. If an item mentions
a behavior that the rater has not observed directly during the rating
period, s/he should extrapolate from other observations of the patient
to make a best guess about how that item should be rated. For example,
patients who are entirely non-verbal must still be rated on the
item “Tends to speak less than he/ she is capable of.”
The scale has shown adequate reliability with a variety of patients
under these instruction conditions.
group of clinicians from a variety of rehabilitation disciplines
who were experienced MARS users revealed that nurses given the MARS
found it easier to complete their ratings when they “scheduled”
a specific time for themselves to spend with (or observing) the
patient, e.g., a half hour over lunch, time spent passing meds,
etc., to make their ratings more comparable to those of team members
who had specific times scheduled with the patient. Team members
agreed that it was most useful to balance their ratings by considering
not the best nor the worst attention observed over the rating interval,
rather trying to capture the average level of attention over the
proscribed time period.
item is rated on a 5-point Likert type scale indicating the degree
to which the item describes the patient’s behavior. Since
items include both positive and negative behaviors, some items must
be “flipped” in direction before any scores are summed.
The total, raw MARS score is the sum of the 22 items (ranging from
22-110), with higher scores indicating better attention.
of the MARS items may also be used to compute 3 factor scores: Restlessness/
Distractibillity (items 1, 10, 12, 17, 22), Initiation (items 7,
13, 19), and Sustained/ Consistent Attention (items 6, 14, 15).
Mean item ratings must be used to compare factor scores due to the
unequal number of items that compose the factors.
attached worksheets (MARS
Scoring Worksheet.xls) allow for semi-automatic MARS scoring.
The first tab aligns reverse-scored and direct-scored items into
the same scoring direction and calculates the total raw MARS score
and mean item Factor scores. The second tab provides a Table for
looking up the logit scores that correspond to raw total MARS scores.
These logit scores convert the MARS to an interval scale for parametric
On 6-7-2010, it was discovered that the scoring sheet posted in
November 2008 contained a typographical error that could affect
the Initiation and Sustained/Consistent Attention subscale scores
(but not the MARS total scores). The spreadsheet was replaced on
6-7-2010; please download the scoring spreadsheet again if you downloaded
it prior to that date. The authors of the MARS regret this error.