Schizophrenia is a serious mental illness that affects over two million Americans and costs about $63 billion in total with $22.7 billion dollars a year for direct treatment and community services, with unemployment comprising an additional $32 billion of non-direct costs1,2. This disorder is typically accompanied by cognitive deficits that precede the onset of psychosis and remain throughout the course of the illness3-8. These cognitive deficits lead to adverse consequences, such as the reduced success in social, vocational, and independent living domains. Impaired cognition is a substantial contributor to functional disability in patients with schizophrenia9. Current antipsychotics are effective at controlling the psychotic symptoms of schizophrenia such as delusions and hallucinations, but these therapies provide minimal cognitive benefits10-13. Pharmacological and nonpharmacological treatments to improve cognitive functioning for patients with schizophrenia are in development at the present time. Cognitive functioning in schizophrenia, both at baseline and as a function of changes associated with treatment, can be reliably assessed by measures with proven sensitivity14. However, FDA guidance mandates that treatment studies demonstrate the clinical meaningfulness of changes in cognitive functioning15,16.
Representatives from the Food and Drug Administration (FDA), the National Institute of Mental Health (NIMH), and the pharmaceutical industry, as well as experts in cognition from academia, met as part of the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) project15. The purpose of the MATRICS project was to develop standard methods in the development of treatments of cognitive impairment associated with schizophrenia. During the course of this work, FDA representatives asserted that cognitive improvements alone, as measured by standardized neuropsychological assessments, are not sufficient to demonstrate drug efficacy for cognitive enhancers. The approval of new treatments for cognitive impairments would therefore require evidence that the cognitive improvements are clinically meaningful15. As a result, clinical trials of cognitive enhancing treatments in schizophrenia now must demonstrate improvement on a standard cognitive measure and improvement on a measure indicating that any cognitive improvements have meaningful benefit to the patient’s functioning. This is known as a ‘co primary requirement’. The MATRICS project made very specific recommendations about which standard cognitive measures would indicate cognitive change, and developed a battery of tests for this purpose.
Although, the MATRICS Group validated a cognitive outcomes battery, the MATRICS Consensus Cognitive Battery (MCCB), they did not recommend that changes in real world functioning should be a prerequisite for the approval of a treatment aimed at cognition. This argument was based on the following concerns: 1) There are many domains of real world functioning in schizophrenia, such as the patient’s ability to hold employment, live independently, and maintain social relationships. 2) Changes in these domains might not be observed in a treatment study because they are likely to take longer than the duration of a typical clinical trial. 3) Furthermore, real world functional change is dependent upon a variety of circumstances unrelated to treatment, such as whether a patient is receiving disability payments17. As a result, the MATRICS group thus recommended that clinical meaningfulness should be demonstrated through the use of tools measuring the potential to demonstrate real world functional improvements associated with cognitive change. At that time, the MATRICS group made no firm recommendations regarding what measure or measures should be used as the ‘co primary measure’, choosing to make “soft” recommendations about the types of co primary measures that might be used in clinical trials18. Current co primary measures used in schizophrenia pharmaceutical trials are of two types: interview based measures and performance based measures.
Interview based measures of cognition are coprimary measures typically completed by the patient or an informant. They include the Schizophrenia Cognition Rating Scale (SCoRS), the Clinical Global Impression of Cognition in Schizophrenia (CGI-CogS), and the Cognitive Assessment Interview (CAI)18-20. These measures have only modest correlations with cognitive performance measures when self reported by patients, in that patients with serious mental illness and other CNS disorders are limited in their ability to accurately report their own cognitive abilities21. Further, although informant ratings have considerable validity, many patients with mental illnesses do not have an informant who can provide meaningful ratings18,22. When informants are available, they can be limited by selective observations of the patient's behavior or a variety of potential response biases.
Performance based measures of functional capacity are measures that require the performance of critical everyday skills in a controlled format. These measures have been found to demonstrate a closer association to cognitive test data than self reports obtained with the interview based measures described above18,21. Several performance based measures have recently been investigated. Two of these, The Maryland Assessment of Social Competence (MASC) and the Social Skills Performance Assessment (SSPA), measure socially oriented functional capacity through a rater's observation of patient behavior during role playing22-24. A more broadly focused and widely used measure of functional capacity is the University of California, San Diego Performance Based Skills Assessment (UPSA)25. The UPSA takes about 30 minutes and measures performance in several domains of everyday living, such as finances, communication, planning, and household activities. The original UPSA has been modified to create both extended versions involving medication management (UPSA-2) and an abbreviated version examining just communication and finances (UPSA-Brief). All versions of the UPSA have been found to have substantial correlations with cognitive performance26.
The UPSA-2 and UPSA-B are currently the preferred coprimary measures, based on a systematic comparative study of their relationships with performance on the MCCB27. However, the different versions of the UPSA have several potential limitations, in terms of lacking alternative forms, inability to deliver the test remotely, and the fact that their paper and pencil format makes rapid development of alternate forms and new assessment scenarios challenging. Further, their use in repeated assessment situations such as clinical trials is limited as some patients perform close to perfectly at their initial assessment. With this in mind, the Virtual Reality Functional Capacity Assessment Tool (VRFCAT) was designed to address these concerns and to reliably assess functional capacity within the context of a simulated real-world environment.
There have been several previous developments in the area of computerized and virtual reality assessments. For instance, Freeman and colleagues28 developed a series of virtual reality simulations that were designed to induce paranoid ideation. In the area of functional capacity assessment, Kurtz and colleagues29 developed an apartment based virtual reality medication management simulation. Finally, a computerized version of the UPSA has also been developed30. This simulation is not a true virtual reality procedure in that an examiner is present and administers the assessments, which are completed on the computer. This test does have the potential for remote delivery, although it is conceptually quite different from a gaming based test.
The VRFCAT (further referred to as “assessment”) is a novel gaming based virtual reality measure of functional capacity that uses a realistic simulated environment to recreate several routine activities of daily living with an eye toward assessment of both baseline levels of impairment and treatment related changes in functional capacity. The assessment’s realistic, interactive, and immersive environment consists of 6 versions of 4 mini scenarios that include navigating a kitchen, getting on a bus to go to a grocery store, finding/purchasing food in a grocery store, and returning home on a bus. The assessment measures the amount of time subjects spend completing 12 different objectives (listed in Table 2) as well as how many errors the subject makes. If a subject takes too much time or commits too many errors, the subject will be automatically progressed to the next objective. Subjects complete the scenarios through a progressive storyboard design. This unique high resolution software application was developed and pilot tested in the NIMH SBIR Phase 1 project with the stated goals of determining the stability and usability of the program (first portion) and measuring the test retest reliability in groups of healthy controls (second portion). After successfully developing the software in collaboration with Virtual Heroes, Inc., a division of Applied Research Associates, Inc., Phase 1 funding also enabled pilot testing of the assessment as well.
Phase 1 usability and reliability pilot testing examined a sample of 102 healthy controls from Durham, North Carolina. The study was approved by the Western IRB and all participants signed an informed consent form. The average age of the subjects included in the reliability portion of the study was 38.1 with a standard deviation of 12.98. The sample was 61% female and 59% Caucasian, 39% African American and 2% other ethnicity. Reliability findings from the Phase 1 pilot testing met expectations with a test-retest ICC of 0.61 and Pearson r of 0.67 despite the use of multiple test versions and relatively few research participants per version. In a previous study with a much larger sample (n=195) of schizophrenia patients, we had found a single form test retest reliability for the UPSA-B of ICC =.76 at a follow up between 6 weeks and 6 months31.
The assessment is currently being tested in an SBIR Phase 2 project that will validate the assessment against other measures of functional capacity and cognition, and examine the ability of this procedure to discriminate a population with schizophrenia from a healthy control group. Part of the goals of the Phase 2 study is the development of normative standards for healthy controls’ performance and understanding the extent of impairment in people with schizophrenia.