Guillain‐Barré Syndrome Disability Scale

Fifty years have passed since the Guillain-Barré Syndrome (GBS) Disability Scale (Table 1) was created as a clinical outcome measure for a randomized trial of treatment with prednisolone published in 1978 [1]. The scale has been used with modifications in most subsequent treatment trials in GBS. In 1984, the British Plasma Exchange trial used a version of the scale which defined some of the grades in more detail (modifications shown in bold type): grade 2 able to walk 5 m without assistance, walking frame, or stick but incapable of manual work including housework, shopping, or gardening; grade 3 = able to walk 5 m with assistance, stick, or walking frame; and grade 5 requiring assisted ventilation for at least part of the day or night [2]. In 1985, the North American Plasma Exchange trial used almost the same version [3]. In 1991, Kleyweg et al. examined some of the measurement properties of a version of the scale in which the grades were defined slightly differently, increasing the distance to be walked from 5 to 10 m (modifications shown in bold type): grade 1 fully capable of manual work; grade 2 able to walk > 10 m without any assistance; grade 3 able to walk > 10 m with a walker or support; and grade 5 assisted ventilation required for at least part of the day. The modified scale had good reproducibility between observers and correlated closely with strength measured with the sum of the scores of 12 muscle groups each measured on the 0 to 5 Medical Research Council scale (MRC-sumscore) [4]. This version of the scale was used in the first randomized trial of intravenous immunoglobulin versus plasma exchange published in 1992 [5]. The 1993 international trial of giving intravenous methylprednisolone with intravenous immunoglobulin added capable of running to the definition of grade 1. It defined the distance to be walked in grades 2 and 3 as 5 m across an open space with the help of one person and a waist-level walking frame, stick, or sticks, not 10 m [6]. The 2004 van Koningsveld trial of intravenous methylprednisolone with intravenous immunoglobulin retained capable of running in the definition of grade 1 but used 10 m as the defining distance to be walked in grades 2 and 3 [7]. Some subsequent studies have included capable of running in the definition of grade 1; others have not; some have used 5 m [8], but most 10 m in the definition of grades 2 and 3; some have made minor alterations to the wording of the grades, and some have not reported the version of the scale being used. The 2004 van Koningsveld trial [7] version has been used more frequently than other versions and is also used in the International GBS Outcome Study (IGOS). To create uniformity, we recommend its use clarified by the notes in Table 2 as the standard GBS Disability Scale. The original GBS Disability Scale [1] was introduced without prior validation to meet the needs of the time. Its simplicity appealed and has led to its continued and ongoing use. However, even our Recommended GBS Disability Scale has limitations: it takes insufficient account of upper limb and cranial nerve disability; the distances between the grades are unequal; some consider the difference between grade 0 and grade 1 unimportant; the use of the ability to run is problematic for people who were not used to/incapable of running before the onset of GBS; and the move from grade 5 to grade 6 is irreversible, unlike the changes between the other grades. It is time to develop and validate a more robust scale to help bring to the bedside promising new treatments such as tanruprubart [9, 10], imlifidase [11], and efgartigimod [12]. Our recommended version of the GBS Disability Scale should be a useful benchmark against which any new scale may be measured. Data sharing not applicable to this article as no datasets were generated or analyzed during the current study.