BJPsych Bulletin | 2021
Difficulties in interpreting patient-reported outcome measures in the absence of a gold standard: the meaning of Clinical Global Impressions scores in liaison psychiatry
Abstract
As a part of routine clinical care, the Ealing Liaison Psychiatry Service (ELPS) uses the Clinical Global Impressions (CGI) scale to assess patient-reported outcomes. We would like to share our findings and the challenges in interpreting CGI ratings. CGI scales in psychiatry were initially used to assess efficacy in clinical drug trials and have since been adapted for use in liaison psychiatry as a part of a nationwide evaluation. The Framework for Routine Outcome Measurement in Liaison Psychiatry proposed that all liaison psychiatry services use CGI scales for consistent data collection and national reporting of outcomes, although there is no guidance on a standard to aim for. Our methodology involved patients and their ELPS clinicians providing a CGI rating on whether the patient’s mental health had improved, not changed or become worse after ELPS contact. This study looked at all 205 patients between January 2018 and November 2019 who had filled out a CGI questionnaire, and the following analyses were made: