ALSFRS-R-SE: an adapted, annotated, and self-explanatory version of the revised amyotrophic lateral sclerosis functional rating scale

Over the course of developing an optimized version of the ALSFRS-R, it became evident that the terms “version” and “variant” have to be distinguished. An ALSFRS-R “version” is defined relative to its place in the evolution of the scale. The predecessor of ALSFRS-R, for example, is the ALSFRS version. Subsequent versions of the ALSFRS-R include the ALSFRS-EX and validated translations in various languages [29‐37] (which raise previously mentioned problems of interpretation). In contrast, “variants” are slight deviations that occur within the original scale. For example, variants may emerge as the result of parallel translations, adaptations by different institutions, or simply through truncation.

A seven-step consensus process with the aim of optimizing the ALSFRS-R was carried out between October 2020 and December 2021 (Fig. 1). The initiative was conducted by members of the “German ALS/MND-NET” – a clinical and scientific network of ALS/motor neuron disease centers with 27 sites in Germany, two partners in Switzerland and one partner in Austria. This consensus group encompassed 18 ALS experts, each with long-standing expertise in ALSFRS-R assessments and ALSFRS-R certifications from at least one, and most often two, organizations.

For linguistic revision and translation into English, a technical editor, a professional translator, and first language editor were brought in, neither of whom have backgrounds in ALS.

A consensus group design [38] was used to develop an optimized version of the ALSFRS-R scale. To assess the existing ALSFRS-R variants in circulation, more than 120 neurologists, researchers, and study nurses within the MND-NET were contacted via e-mail and asked to share the German-language ALSFRS-R forms that they were using at the time.

Optimizing the ALSFRS-R scale to closely adhere to the standard English-language version [1] took the following factors into consideration: (1) Since the assessment process conducted by healthcare professionals and the self-assessments performed by patients and patient caregivers are well established, the ALSFRS-R should be accessible to both healthcare professionals and patients. In order to facilitate this, there should be no ambiguity surrounding the language of the individual diagnostic items. (2) Adding explanatory language to the scale items and reply options may reduce ambiguity as well as the need for ALSFRS-R training. (3) As ALSFRS-R assessments through computers, mobile devices, and other remote digital means are increasingly common, it is important to consider the scale’s use and suitability for these media.

Nine German language variants of the ALSFRS-R were collected, three of which already contained instructions for self-assessment. Six variants were individual translations of the original English version for external evaluation. Figure 2 depicts the schematic process of consolidating the pre-existing English scale and nine German variants of the ALSFRS-R. The additional files includes the German and English-language versions of the ALSFRS-R-SE that emerged from the consensus process [see Additional file 1 and Additional file 2].

The ALSFRS-R is a functional scale that measures deviations from unrestricted or "normal" motor functioning as caused by ALS. The two major symptoms that present in ALS and limit functionality in specific areas are muscle weakness and stiffness. Muscle weakness is caused predominantly by the loss of the second motor neuron. Muscle stiffness often, but not always, results from spasticity, indicating degeneration of the upper neuron [39]. If possible, complaints that are not related to ALS-such as orthopedic issues that might affect functional areas-should be excluded from the evaluation. There are two ways to do this: Firstly, functionality should always be assessed in relation to the person’s status before the onset of ALS symptoms; and secondly, conditions that are obviously unrelated to ALS should be excluded from the assessment even if they lead to functional impairment.

To ordinally scale the loss of functionality, anchor points grade functionality from 0 to 4 for each item. To determine an ordinal score, the scale considers whether there is an increased need for assistance or assistive devices. The most unambiguous scores are 4, which designates unrestricted functionality, and 0, which designates a complete loss of functionality. Whereas the latter score can be identified by the full-time use of assistive procedures or devices, differentiating between intermediary scores can be difficult. A mild impairment (score 3) should reflect a condition that does not yet require compensatory help. Score 2 is characterized by intermittent use of compensatory measures. Score 1 is given if assistive procedures or devices are needed in all instances, and independence is severely reduced but not entirely lost. These considerations apply to the first nine items and to item 11. With regard to respiratory items 10 and 12 functional compensation (i.e., mechanical ventilation) is implied either at the 0-point level (item 10: dyspnea) or already at the 3-point level (item 12: respiratory insufficiency). This change does not eliminate the structure of those items, but instead shifts the anchor points in a given direction.

The specific moment in which personal assistance, technical support, or other substituting procedures are first used may be influenced by several factors, including the personal convictions of the affected person and the availability of assistive options such as PEG or mechanical ventilation. Since circumstantial considerations do not necessarily reflect an affected person’s functional capacity, they should not overrule the implicit logic of an item.

To illustrate the operation of the ALSFRS-R and to standardize its application, an explanatory introduction was included (see bottom of Table 1). The introduction instructs any individual using the ALSFRS-R-health care professional, family member, or a patient-to carefully review the response options and their corresponding comments and to select the most applicable answer. With regard to pre-existing functional limitations, the recommendation is to score the item as “normal” or "unrestricted" by ALS (4 points). This recommendation should be waived only if ALS symptoms have exacerbated a pre-existing impairment. Once an approach is chosen, it should be followed consistently across all items and in future ALSFRS-R assessments.

Table 1 compares the revised items in the ALSFRS-R-SE to those in the original ALSFRS-R scale. All changes are classified and evaluated. Adjustments made to individual items within the four scoring domains are described in the following sections. The wording of the English and German scales may not be perfectly identical due to linguistic differences.

Item 1 (Speech): In contrast to the frequent use of the word "language" in the German variants, this discrepancy was balanced by consistent use of the term "speech." In the explanatory notes, "speech" was further subdivided into "phonation" and "articulation” in order to cover these both aspects of speech production. Item 2 (Salivation): Adverbs such as "occasionally" or "often" are used to describe the frequency of an occurrence. This also applies to saliva collection and its associated methods, such as use of a tissue. Item 3 (Swallowing): To more precisely describe this item, explanations were augmented to include descriptions such as "more careful swallowing" or "smaller bites." The reference to an "early eating problem" was replaced by the more specific "minor swallowing problem." Differences between various kinds of food consistencies were clarified with examples. Language concerning the use of an enteral feeding tube was explicitly contextualized in terms of dysphagia and explained in general terms.

Item 4 (Handwriting): An explanation appended to this item clarifies that it refers to the dominant (writing) hand in the usual posture. The use of writing aids was included within the criteria for point 2. The ability to write only one’s signature is considered applicable to meet the criteria for score 1. Item 5a (Cutting food and handling utensils, without gastrostomy): The altered use of cutlery in the context of a functional limitation is explained with examples. Adverbs such as “on occasion” or “on most occasions” indicate the degree of impairment or the need for help. For purposes of harmonizing the complete loss of functionality across all items, score 0 was defined as total dependence with regard to all activities in question. This includes elimination of imprecise descriptions, such as the phrase "must to be fed." Item 5b (Cutting food and handling utensils, with gastrostomy): The extent to which a patient is dependent from a caregiver when handling a feeding tube is specified by score points 1 and 2. Item 6 (Dressing and hygiene): The degree to which assistance or accommodations are needed for certain tasks related to dressing and personal hygiene (such as wearing clothes that are easy to put on and remove, or showering while sitting down) are explained in greater detail.

Item 7 (Turning in bed and adjusting bed clothes): The explanation to this item takes into account the gradual transition from independence without increased effort (score 4) to any need for personal assistance (scores 1 and 0). It is also explained how to assess the effort it takes to perform the activity without help (scores 3 and 2). Item 8 (Walking) Problems with walking are further described to include issues of unsteadiness and stumbling. The use of walking aids is explicated, and the explanation specifically accounts for patients who must hold onto objects for support. The ability to stand (e.g., for transfer) as a targeted leg movement is introduced as an explanatory example (score 1). Item 9 (Climbing stairs) For this item, language is included to account for the necessity of a handrail (score 1) and non-essential use of a handrail (score 2).

Item 10 (Dyspnea): The phrase "dyspnea and shortness of breath" is consistently used to describe symptoms. Score 3 designates the occurrence of these symptoms during normal walking or moderate (physical) activity. Score 2 symptoms, by contrast, are related to low-intensity activities, which now include “talking for longer periods of time.” The actual use of non-invasive ventilation to treat dyspnea and shortness of breath unambiguously lead to score 0. Item 11 (Sleep disturbances due to breathing problems, formerly “orthopnea”): The explanation for this item specifies that if mechanical ventilation is usually provided, but sleep is still possible without it, breathing should be assessed without the use of ventilation. As the term "orthopnea" does not accurately reflect the spectrum of sleep-related symptoms caused by respiratory impairment, we have chosen to revise the title of this item. Moreover, as reflected in the criteria for score 3, patients may be able to tolerate a flat lateral position while being unable to lie on their back. Sleep disturbances due to respiratory impairment have to be considered most severe when mechanical ventilation is indispensable to achieve acceptable sleep quality (score 0). Item 12 (Mechanical ventilation): Continuous positive airway pressure for treatment of obstructive sleep apnea must not be equated with non-invasive ventilation (NIV). Score 0 is assigned when invasive ventilation procedures are in use. Scores 1–3 are calculated via the amount of NIV use during a 24-h period. If a period equals or exceeds the duration of nighttime sleep but is below permanent dependence (22 h), score 2 is assigned.