[2][3] Since their introductions, both the original and extended versions of the scale have been widely adopted in clinical practice, as well as in research studies on brain injury.
[3] The Glasgow Outcome Scale was first described by Bryan Jennett and Michael Bond in 1975 as a tool to characterize both survival and quality of life after brain injury.
Throughout the 1980s and 1990s, studies assessing the reliability of both the original and extended version of the GOS found that there was significant inter-rater variation in how patients were ranked on the scales based on the differences in background of the assessor.
[4][5] To address this and achieve greater consistency among different assessors, a structured interview format with clearer guidelines was developed in 1998 for both the GOS and GOSE.
[6][9] The Extended Glasgow Outcome Scale further includes assessment of other problems caused by or related to the initial injury, such as headaches, migraines, fatigue, or memory difficulty.
The Glasgow Outcome Scale-Pediatric Revision (GOSE-P) adjusts the interview questions to account for age and developmental differences in pediatric patients.
This resulted in the development of a structured interview format with detailed guidelines to improve reliability and consistency between different raters.
Shortly after the development of the structured interview guidelines, it was reported that use of this format greatly improved the reliability of both the GOS and GOSE.