Assessment of catatonia and inter-rater reliability of three instruments: a descriptive study

Clinical assessment of catatonia includes the use of diagnostic systems, such as the Diagnostic and Statistical Manual, Fifth Edition (DSM-5) and the International Classification of Disease, Tenth Revision (ICD-10), or screening tools such as the Bush Francis Catatonia Screening Instrument (BFCSI)/Bush Francis Catatonia Rating Scale (BFCRS) and the Braunig Catatonia Rating Scale. In this study, we describe the inter-rater reliability (IRR), utilizing the BFCSI, BFCRS, and DSM-5 to screen for catatonia.

Data from 10 participants recruited as part of a larger prevalence study (of 135 participants) were used to determine the IRR by five assessors after they were trained in the application of the 14-item BFCSI, 23-item BFCRS, and DSM-5 to assess catatonia in new admissions. Krippendorff's α was used to compute the IRR, and Spearman's correlation was used to determine the concordance between screening tools. The study site was a 35-bed acute mental health unit in Dora Nginza Hospital, Nelson Mandela Bay Metro. Participants were mostly involuntary admissions under the Mental Health Care Act of 2002 and between the ages of 13 and 65 years.

Of the 135 participants, 16 (11.9%) had catatonia. The majority (92 [68.1%]) were between 16 and 35 years old, with 126 (93.3%) of them being Black and 89 (66.4%) being male. The BFCRS (complete 23-item scale) had the greatest level of inter-rater agreement with α = 0.798, while the DSM-5 had the lowest level of inter-rater agreement with α = 0.565. The highest correlation coefficients were observed between the BFCRS and the BFCSI.

The prevalence rate of catatonia was 11.9%, with the BFCSI and BFCRS showing the highest pick-up rate and a high IRR with high correlation coefficients, while the DSM-5 had deficiencies in screening for catatonia with low IRR and the lowest correlation with the other two tools.