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Research Overview

“The Vegetative State and the Minimally Conscious State are possibly the least understood and most ethically troublesome conditions in today’s medicine.”

Stefano Peca, Ph.D.

In 2014, ARBI’s team of therapists finished developing the Comprehensive Assessment Measure for Minimally Responsive Individuals (CAMMRI).

The CAMMRI is an integrated, functional measure developed to objectively identify and track the incremental changes in adults who demonstrate minimal responsiveness to their environment as a result of severe acquired brain injury.

CAMMRI is divided into three major areas:

1. Response to the environment

2. Motor control

3. Communication and swallowing

Each area has specific sub-tests that can be used independently or as part of the overall measure. The sub-tests are scored using a 7-point scale. For all items, the higher the score, the higher the level of function. The highest scores are representative of consistent and differentiated responses to command/stimuli or spontaneous/prompt responses to commands.

All the sub-tests are compiled in the CAMMRI manual published by ARBI as a reference for therapists that would like to use the measure. The CAMMRI manual includes the guidelines with detailed explanation of the sub-tests and clinical studies as examples of the application of the measure and scoring system.

Completed data for this project and development of the measure and references were submitted for publication in the Brain Injury Journal.

For further information on the CAMMRI or to obtain the manual free of charge, please contact: ana@arbi.ca

Click here to read an article about the CAMMRI published in Brain Injury, Volume 29, Issue 12, 2015.



The Comprehensive Assessment Measure for Minimally Responsive Individuals (CAMMRI) was developed by a team of therapists including occupational therapists, physiotherapists and speech language pathologists at the Association for the Rehabilitation of the Brain Injured in Calgary, Canada. ARBI’s team found that existing assessment measures lacked sufficient clinical sensitivity to detect changes in individuals with the most severe brain injury. Current measures do not adequately address functionality that is so important in diagnosis, prognosis and treatment planning to improve the quality of life of these individuals.  ARBI’s therapists responded to the need by developing this highly sensitive assessment tool to measure and monitor responsiveness to environmental stimuli, communicative abilities, swallowing status and motor responses over the course of the rehabilitative process.

After a severe brain injury, many patients remain in coma for a certain period of time and later progress to a Vegetative State and then to a Minimally Conscious State. In the Vegetative State there is no awareness of self or environment and purposefulness or voluntary response to visual, auditory, tactile, or noxious stimuli (Giacino & Kalmar, 2005). The individual in a Minimally Conscious State shows preliminary indications of arousal and interaction with the environment, demonstrating some cognitive processing capacity (Giacino et al., 2002).

In the literature, we found much discussion that unfortunately affirms that the misdiagnosis between levels of awareness in severe brain injury is not uncommon. The rehabilitation plans, prognosis, and family’s hope are critically entwined with an accurate diagnosis. “There is no neuro-diagnostic or laboratory test that allows the clinician to diagnose vegetative state per se; instead, the diagnosis can be made only by serial bedside neurobehavioral assessment” (Giacino et al., 1997).

Although initially developed to objectively identify and track incremental changes in adults who demonstrate minimal responsiveness to their environment as a result of acquired brain injury, there appeared to be good support that the CAMMRI neurobehavioral assessment measure could serve extended clinical functions as an important tool for clinicians to better categorize the level of response, diagnosis and prognosis for individuals with severe brain injury.

With this purpose in mind, the ARBI team of therapists completed an extensive literature review in order to evaluate the measurement tools that currently exist to assess this level of brain injury. The following scales were researched:

  • Sensory Modality Assessment Rehabilitation Technique (SMART)
  • Functional Status Examination (FSE)
  • Functional Independence Measure (FIM)
  • Disability Rating Scale (DRS)
  • Sensory Stimulation Assessment Measure (SSAM)
  • Neurobehavioral Cognitive Status Examination (Cognistat)
  • Western Neuro Sensory Stimulation Profile (WNSSP)
  • JFK Coma Recovery Scale (CRS)
  • Chedoke-McMaster Impairment Inventory (CMII)

The literature review confirmed that none of the above measures offered sufficient sensitivity to detect behavioral changes and response to stimuli in severely brain injured individuals in all of the categories that the CAMMRI addresses. CAMMRI includes more types of sensory stimulation, means of communication and motor control abilities and these are necessary to more fully understand the individual’s full capability to perceive and interact with his world.

At the same time, several current measures have good clinical sensitivity in particular areas and can be used to support the construct validity of the CAMMRI. While the Western Neuro Sensory Stimulation Profile (WNSSP), the Johnson Rehabilitation Institute Coma Recovery Scale (CRS) and the Chedoke-McMaster Impairment Inventory (CMII) all show similarities to the CAMMRI, the CAMMRI is a more comprehensive scale designed to be used efficiently by clinical staff.

Description of the CAMMRI

The CAMMRI is divided into three major assessment areas: response to the environment, motor control and communication/swallowing. Each area is queried with specific sub-tests, which can be used independently or as part of the overall measure. The subtests in each area are:

  • Response to the environment: Visual response, olfactory response, auditory response, tactile response and arousal response subtests assess sensory responses to the environment.
  • Motor Control: The motor control subtest analyzes motor responses made with the head and upper and lower extremities in order to determine the best motor response.
  • Communication and Swallowing: Subtests for facial/gestural communication, yes/no response, vocalization, auditory comprehension response, dysphagia scale, and augmentative/alternative communication assess the potential for following commands, communicating and the ability to use augmentative devices.

Each subtest was constructed to capture and quantify the best response of the individual and thus identify the subtle signs of awareness, as well as their fluctuations. A standardized behavioral assessment measure greatly assists clinicians to follow the same criteria over time and facilitate the development of a treatment plan.

A description of each subtest, scoring procedure, recording form, scale and a scoring sample follows in later chapters of the manual.

Results of the CAMMRI Pilot Project

ARBI’s clients, who were functioning at level II or III on the Rancho Los Amigos Scale, participated in the CAMMRI testing. A consent form was signed by a family member or guardian, and all the assessments were administered on ARBI’s premises or, when respiratory support was necessary, at the client’s residence. All clients were medically stable during the course of the assessments.

The pilot project included 12 subjects. While it is recognized that this is a small sample, it is deemed to be representative of the low number of very severe brain injured persons seen in the general population of those with brain injuries. The sample included 58% anoxic brain injury, 34% traumatic brain injury and 8% stroke.

The methodological design employed for development of a new measure followed the recommendations of Guyatt, Bombardier & Tugwell (1986). After the initial assessment, a subsequent evaluation was conducted one year later, in order to determine improvement or deterioration. The design of the pilot project is described below:

  • content validity based on literature review, prior qualitative research using the critical incident technique (LeNavenec & Reimer, 2002) and expert opinion;
  • initial assessment by two therapists assessing and scoring the client at the same time;
  • construct validity based on expected significant correlations with similar and standard measures (i.e. Johnson Rehabilitation Institute Coma Recovery Scale Revised, the Western Neuro-Sensory Stimulation Profile, and the Chedoke-McMaster Stroke Impairment  Inventory);
  • re-assessment and inter-rater reliability through pilot testing where two therapists again assessed the client at the same time;
  • internal consistency where subtest components made this feasible;
  • comparing scores on initial assessment and one year later to determine responsiveness using reliable change scores; and
  • qualitative and quantitative analysis to define benchmark.

All assessments were videotaped for future analysis and reference.

All data were coded and entered into SPSS (v. 13). Analysis of demographics and subtest items were undertaken using frequencies for categorical items and calculation of means, standard deviation and range for interval and ratio items. Inter-item correlations and Cronbach’s alpha were calculated for subtests as appropriate. Correlations with standard measures of similar and differing constructs were examined for evidence of construct validity, based on predetermined hypotheses.

Results of Data Analysis

  • The average inter-rater reliability between the same scales tested by two different therapists is 0.9, including two sub-tests with Cronbach’s Alpha coefficients of 1.0, representing an impressive inter-rater reliability score for this measure.
  • Correlations between the CAMMRI and the other standard assessment measures of similar and differing constructs were examined for evidence of construct validity. The measures used for comparison are: Western Neuro Sensory Stimulation Profile (WNSSP), the Johnson Rehabilitation Institute Coma Recovery Scale (JFK) and the Chedoke-McMaster Impairment Inventory (CMII).
  • The data analysis confirmed the hypothesis indicating that the Western Neuro Sensory Stimulation Profile (WNSSP) is the measure most similar to the CAMMRI. The two measures show a pattern of correlations on average of 0.5. However, the WNSSP is not as comprehensive as the CAMMRI because it does not include a motor response component.
  • The Johnson Rehabilitation Institute Coma Recovery Scale (JFK) correlated on an average of .4 with the similar subtests of the CAMMRI. The CAMMRI includes 12 subtests for a complete assessment of the client whereas the JFK only assesses 6 areas.
  • The Chedoke-McMaster Impairment Inventory correlated on an average of .4 with the corresponding CAMMRI scales, and only assesses the motor responses of the clients.
  • Based on these data, there is a moderate correlation, on average, between the CAMMRI and the above-mentioned scales. This supports our assertion that the CAMMRI measures the various key areas tapped by other scales while its comprehensiveness nature further provides a more detailed and precise understanding of the client.

A questionnaire asked all therapists involved in the CAMMRI Pilot Project to rank their opinion from 1 to 5 (disagree to strongly agree) on the clinical use and applications of the CAMMRI, WNSSP, JFK and CMII. The results in the areas that are more relevant for the study are summarized. (A complete questionnaire and data analysis is available upon request.)

Descriptive statistics showed that on the questions related to test instructions being easily followed and understood, all tests showed similar results, averaging 4.0 (range: 3.57 to 4.75).

For the question related to the relevance of the test for the population tested, the CAMMRI was given the highest score (all 5s) and the WNSSP, next highest (4). The other two tests averaged lower scores (2).

Another question addressed the importance of the information obtained on the test to capture the client’s progress. Again, CAMMRI scored the highest (5). All the other scales showed an average of 2.5.

This data confirmed that the CAMMRI is a sensitive measure and addresses all the necessary areas needed to provide a comprehensive understanding of the clientele. Furthermore, the CAMMRI correlated with results from other scales on related areas of assessment.

Summary of Results

The clinical findings yielded by the CAMMRI gives us an opportunity to accurately measure and assess the current functioning of our clients and will also be sensitive to changes in a client’s rehabilitation process. These preliminary results show that the CAMMRI allows professionals to be better equipped to evaluate treatment techniques and efficacy issues and, in turn, develop a more sensitive rehabilitation program for clients.


The CAMMRI target population is adults who have experienced severe brain injury secondary to trauma, anoxia or CVA, and who currently function at level II or III on the Rancho Los Amigos Scale. It can be used as a bed side behavioural assessment in the acute and sub-acute stage of recovery to quantify and yield comprehensive baseline descriptions which then can be used to better plan rehabilitation, predict outcomes or determine rehabilitation potential, and to plan for improved continuity from hospital to community.

The sub-tests can also be used as stand-alone measures to track changes or fluctuations in a particular area of interest. One or more subtests may be administered more frequently depending on the responses the client displays and the need to monitor them. For example, if a client is shown to be becoming more awake and responding to visual stimuli, those two sub-tests may be re-administered daily if the staff wishes to document improvements or fluctuations in these two areas. The entire CAMMRI need not be re-administered.

Also, it may be possible to apply the CAMMRI or individual subtests in the assessment of other disability populations, such as MS, stroke and other neurological conditions. Reliable tracking of an individual’s consistent response patterns, swallowing status, communication and/or ability to use environmental control systems can often be established; however, further studies may be necessary to pursue this course.

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