Development and Evaluation of a Cognitive Battery for People With Schizophrenia in Ethiopia.

BACKGROUND AND HYPOTHESIS: Cognitive difficulties significantly burdened people with schizophrenia (PWS). However, cognitive assessment is often unavailable in low- and middle-income counties (LMICs) due to a lack of validated and culturally adapted cognitive assessment tools. In this study, we developed and evaluated a culturally sensitive cognitive battery for PWS in Ethiopia.

STUDY DESIGN: This study was conducted in three phases. First, we selected appropriate tests through an instrument selection procedure and created a new battery. Then, we rigorously adapted the tests using culturally competent procedures, including cognitive interviewing and expert meetings. Finally, we tested the new battery in 208 PWS and 208 controls. We evaluated its psychometric properties using advanced statistical techniques, including Item Response Theory (IRT).

STUDY RESULTS: The Ethiopian Cognitive Assessment battery for Schizophrenia (ECAS) was developed from three different batteries. Participants reported tests were easy to complete, and the raters found them easy to administer. All tests had good inter-rater reliability, and the composite score had very high test-retest reliability (ICC = 0.91). One-factor structure better represented the data with excellent internal consistency (α = .81). ECAS significantly differentiated PWS from controls with 77% sensitivity and 62% specificity at a Z-score ≤0.12 cut-off value. IRT analysis suggested that the battery functions best among moderately impaired participants (difficulty between -0.06 and 0.66).

CONCLUSIONS: ECAS is a practical, tolerable, reliable, and valid assessment of cognition. ECAS can supplement current assessment tools in LAMICs for PWS and can be used to measure cognitive intervention outcomes.