Introduction
In the realm of mental health, mood disorders like Major Depressive Disorder (MDD) and Bipolar Disorder (BD) are often characterized by emotional symptoms. However, clinicians and researchers increasingly recognize that "cognitive fog"—deficits in memory, attention, and executive function—is a primary driver of functional disability. To address this specific clinical need, Richard S. E. Keefe, Kolleen H. Fox, Vicki G. Davis, and their colleagues developed the Brief Assessment of Cognition in Affective Disorders (BAC-A). Published in the Journal of Affective Disorders around 2013-2014, the BAC-A was engineered to provide a brief, sensitive, and specific assessment of cognitive impairment specifically for the affective disorder population. With over 70 citations and a reputation for psychometric rigor, it has become an indispensable tool for those looking to move beyond mood symptoms to the objective measurement of cognitive health.
This article dives deep into BAC-A, by providing a detailed and thorough description of its structure and applications, while acknowledging its limitations and shortcomings.
Key Features of the Brief Assessment of Cognition in Affective Disorders (BAC-A)
Purpose and Use
The primary purpose of the BAC-A is to identify and quantify cognitive impairment in individuals experiencing mood disorders. It serves as a bridge between lengthy, traditional neuropsychological batteries and the need for a practical, "bedside" assessment that can be used in busy clinical or research environments
Target Population
The BAC-A is validated for adults aged 18 and older, including:
Young Adults (18-24 years)Middle-Aged Adults (25-44 years)Older Adults (45-64 years)Seniors (65+ years)While it is broadly applicable to the adult population, it is specifically designed for:
Individuals with Bipolar Disorders (BD)Individuals with Major Depressive Disorder (MDD)Structure
The BAC-A is not a self-report questionnaire but a series of 6 performance-based cognitive tests. These tests cover a wide range of neuropsychological domains:
Verbal Memory (List Learning): Measuring immediate and delayed recall of a 15-word list.Digit Sequencing Task (Working Memory): Assessing the ability to hold and manipulate information.Token Motor Task (Motor Speed): A timed task involving the placement of tokens to measure physical dexterity and speed.Verbal Fluency (Semantic and Phonemic): Categorical (e.g., naming animals) and letter-based word generation.Symbol Coding (Processing Speed): A 90-second task focused on rapid visual-motor coordination.Tower of London (Executive Function): A reasoning and problem-solving task involving specific moves and time constraints.Affective Interference Test: Some versions also include a component for attention and vigilance under emotional distraction.Scoring Method
Scoring the BAC-A involves a transition from raw counts to standardized data.
Raw scores:
Each of the six tests generates a raw score.
Test
Raw score
Max raw score
Verbal Memory (VMI)
Total number of words recalled correctly
75
Working Memory (WM)
Total number of correct sequences
21
Motor Speed (MS)
Total number of tokens placed correctly in a container within 60 seconds
-
Verbal Fluency (VF)
Total number of correct words generated across all categories and letters
Varies
Attention & Processing Speed (AS)
Total number of correct symbols coded within 90 seconds
-
Executive Function / Reasoning & Problem Solving (EF)
Total number of correct problems solved
15
Standardization
Raw scores are converted into Z-scores based on normative data matched for age, sex, and education. This allows the clinician to compare a patient's performance against a healthy reference group. While there is no single diagnostic "cut-off," a composite Z-score of ≤ -1.0 or -1.5 is often used in research to indicate clinically significant impairment.
Administration Format
The BAC-A is a clinician-administered tool. It is administrated via:
Paper formsIn‑person interviewsCompletion typically takes between 15 to 30 minutes, making it much faster than traditional batteries. However, it does require basic training to ensure standardized administration and scoring.
Applications of Brief Assessment of Cognition in Affective Disorders (BAC-A)
The BAC-A is highly versatile in specialized settings:
Screening: Identifying "hidden" cognitive deficits that might hinder treatment adherence.Monitoring: Tracking cognitive recovery as mood symptoms stabilize.Treatment Planning: Designing cognitive remediation strategies or adjusting vocational expectations based on executive function scores.Research: Providing an objective outcome measure for clinical trials investigating the pro-cognitive effects of new medications or therapies.Languages and availability
To support global clinical research, the BAC-A is available in several major languages:
EnglishFrenchSpanishPortugueseTurkishItalianThe BAC-A is a proprietary tool. Access requires permission and a fee for commercial licensing, and the manual must be obtained through official channels to ensure valid interpretation.
Reliability and Validity
The tool is categorized as highly reliable, with a Cronbach's alpha ranging from 0.80 to 0.90, which is excellent for a brief cognitive battery. Furthermore, it demonstrates strong construct validity, convergent validity with larger batteries (like the MCCB), and discriminant validity in successfully differentiating patients with affective disorders from healthy controls.
Original validation study linkItalian Validation Study linkLimitations and Considerations
Expert users should keep the following challenges in mind:
Scoring Complexity: The conversion from raw scores to Z-scores requires careful attention to normative tables.Administration Complexity: It is more difficult to administer than a simple Likert-scale questionnaire and requires trained personnel.Cultural Bias: Performance-based tasks can be sensitive to cultural and educational backgrounds.Social Desirability Bias: Some patients may experience performance anxiety or attempt to mask deficits during in-person testing.Other Versions And Related Questionnaires
The BAC-A is part of a broader ecosystem of cognitive assessment tools:
BAC-App: A digital adaptation for modern clinical workflows.THINC-it®: A separate but related digital cognitive tool developed by the same research group.MCCB (MATRICS Consensus Cognitive Battery): A more comprehensive, albeit longer, battery.SCIP (Screen for Cognitive Impairment in Psychiatry): A complementary screening tool.Digit Symbol Substitution Test (DSST): A brief neuropsychological test measuring cognitive processing speed, sustained attention, and working memory.Trail Making Test (TMT): Measures visual attention, processing speed, and mental flexibility.Additional Resources
A direct link to the Original Validation StudyFor more information, you can contact the author using the following E-mail: keefe@duke.eduFrequently Asked Questions (FAQ)
Who can use the BAC-A?Researchers and clinicians assessing cognition in adult patients suffering affective disorders.
How long does it take to complete the BAC-A?It can be usually completed in approximately 15–30 minutes.
How is the BAC-A administered?It can be administrated by trained professionals as a 6 performance-based tasks.
Is there any cost to using the BAC-A?it is a proprietary tool requiring licensing for professional and commercial use.
A Word from ResRef about the Brief Assessment of Cognition in Affective Disorders (BAC-A)
The BAC-A is an indispensable, psychometrically robust tool specifically engineered for the clinical reality of cognitive dysfunction in affective disorders. Its brief nature allows for practical implementation in busy clinical settings, while its comprehensive scope covers key cognitive domains. It is highly recommended for clinicians and researchers seeking a validated measure to objectively assess and monitor cognition in patients with depression and bipolar disorder.
References
Keefe, R. S., Fox, K. H., Davis, V. G., Kennel, C., Walker, T. M., Burdick, K. E., & Harvey, P. D. (2014). The Brief Assessment of Cognition In Affective Disorders (BAC-A):performance of patients with bipolar depression and healthy controls. Journal of affective disorders, 166, 86–92. LinkRossetti, M. G., Bonivento, C., Garzitto, M., Caletti, E., Perlini, C., Piccin, S., Lazzaretti, M., Marinelli, V., Sala, M., Abbiati, V., Rossi, R., Lanfredi, M., Serretti, A., Porcelli, S., Bellani, M., Brambilla, P., & GecoBip Group (2019). The brief assessment of cognition in affective disorders: Normative data for the Italian population. Journal of affective disorders, 252, 245–252. Link