Nutech Functional Score (NFS), a New Scoring System to Assess the Level of Impairment in Patients with Cerebral Palsy

Background: A non-progressive disorder cerebral palsy (CP) occurs as a result of the damage to the brain of a fetus and newborns. It is estimated to affect every one in 323 children in the U.S. The Gross Motor Function Classification System (GMFCS) has been a validated and reliable tool used for assessing the gross motor function in patients with CP. However the use of tool has been found to be limited in assessing certain symptoms of CP that are essential to be evaluated. Our study aimed at developing a scoring system that can assess the symptoms which remained untouched in GMFCS. Methods and Findings: We initiated compiling the lists of symptoms from the diagnostic records of the cases who visited our facility. CP patient who were previously assessed with GMFCS, were then assessed using Nutech Function Score (NFS), the new scoring system. NFS is a 32 point positional and directional scoring system that can assess the CP symptoms that remain far from assessment in GMFCS; these symptoms are feeding, indication, epilepsy, toilet training, drooling, mathematical skills, hearing, vision, commands, smiling, constipation, recognition/awareness, eye contact, aggression, speech, breathing difficulty, defense mechanism and swallowing. As opposed to GMFCS, NFS scoring system can be used to assess patients aged above 18 years. We have also converted the scores into numeric grades. Conclusion: NFS appears to be a unique tool that can be used glo-bally to assess the improvement in patients with CP.


Introduction
Cerebral palsy (CP) is a devastating group of nonprogressive movement and posture related disorders that most commonly affect children. It occurs as a result of the damage to the brain of a fetus and newborns. [1] According to the estimation by the Centers of Disease Control (CDC) in the U.S., every one in 323 children is affected by CP. [2] The movement disorders that might occur in the CP patients are; spasticity (stiff muscles), dyskinesia (uncontrollable movements) and ataxia (poor balance and coordination). Based on the type of movement disorder involved, CP has been divided into four types which include spastic CP, dyskinetic CP (choreoathetoid, athetoid, and dystonic cerebral palsies), ataxic CP and mixed CP. Spastic CP, the most common form of CP, affects around 80% of people with CP. [3] Several scoring systems have been developed that aimed to assess the level and extent of impairment in patients with CP including the Gross Motor Function Classification System (GMFCS), the Manual Ability Classification System (MACS) and Bimanual Fine Function (BFMF). [4][5][6] Both GMFCS and MACS tools have been used internationally. Previous studies have shown them to be valid and reliable. [6,7] This paper will reflect on the presently used GMFCS scoring system. GMFCS classifies the gross motor function in patients with CP based on selfinitiated movement; especially their ability to walk and stand. [8]. However, evaluation of a patient with CP using GMFCS poses certain limitations. Firstly, it does not assess certain parameters that are essential to be evaluated in the patients with CP which include epilepsy, hearing, drooling, writing, mathematical skills, communicating and playing. (Figure 1) Secondly, distinction between first two levels of GMFCS is unclear, mainly for children below the age of 2 years. [8] Thirdly, the scoring is not numeric, i.e., we cannot add or subtract the grades.
Our facility has been treating patients with CP since 2000. While grading the CP patients with GMFCS scoring system, the doctors felt it difficult to grade several parameters. This led to the development of Nutech Functional Score (NFS), a new scoring system, in 2004. The new scoring system called NFS is a numeric scale that scores almost all the known symptoms for patients with CP. Several parameters are assessed in NFS, but are not included in GMFCS. However, these parameters are essential to be assessed in CP patients.  The paper will discuss about the development of NFS and will compare it with the GMFCS, an internationally used scoring system.

Methods
The study included CP patients who visited our facility either with the previous diagnosis of the condition or were diagnosed at the institute by routine medical procedure for the diagnosis. Both, common or rare symptoms of the condition with which the patient was evaluated were documented in the diagnostic history. In 2004, the institution started compiling the lists of symptoms from the diagnostic records of the cases. Thus, the patient can be evaluated based on the list of symptoms. These lists are continuously revised to maintain the accuracy.
A symptom is evaluated based on five ordinal grades running in BAD → GOOD direction. We used NFS, the new scoring system, to assess CP patients who were previously assessed with GMFCS. We have converted the grades into numeric values required for probability based studies.

Results
We have developed a 32 point positional and directional scoring system that assesses the patients with CP. It covers all the known symptoms of a patient with CP that are important to assess the patient with CP. These symptoms include feeding, epilepsy, indication, toilet training, mathematical skills, drooling, hearing, vision, commands, smiling, recognition/awareness, constipation, eye contact, aggression, speech, defense mechanism, breathing difficulty and swallowing. The symptoms along with their grades are presented in Appendix 1. However, if the symptoms were found not to be associated with the ailment, they were graded as not afflicted ailment (NAA). If any of the patients was too young to respond to the diagnosis of symptom then it was graded as too young to elicit (TYE).

Parameter Description Score
Not Afflicted NAA

Hearing
No hearing 1 Can hear with source close to ear 2 Only loud noise from three meters 3 Only loud noise from ten meters 4 Hearing > 10 meters 5 Can close fingers, hold objects but cannot release 4 Grip better than in grade 4 5 Each symptom is categorized into five ordinal grades (1,2,3,4,5) in BAD → GOOD direction. These five numbers from 1 → 5 represents worst, bad, not so bad, good and normal, respectively. NFS is ordinal as it tells the condition of the case from Bad to Good. The spread of five grades of a symptom i.e., 1, 2, 3, 4 and 5 lies in a hypothetical categorical range of 0.5 and 5.5, so as to keep the grades equidistant from each other and continuous. In probability-based studies, a range of (-1, 1) or at least the range of (0, 1) is required, so the grades are converted to respective numeric values. The '0.5' and '5.5' of hypothetical categorical range (0.5, 5.5) is considered as '0' and '1' of the (0, 1) numeric scale, respectively. The configuration can be used for one symptom and is now universal. For Y n = numeric score and Y c = categorical score, the relationship at any value of 'x' will be . The conversion of the grades is presented in Table 1. This layout can be used universally to convert five categorical grades (range; 0.5 to 5.5) to five numeric grades (range; 0 to 1) or three categorical grades to three numeric grades (range; 0, 1) depending upon the symptoms of parameters assessed by NFS.

Discussion
Children with CP need to be assessed carefully to establish the intensity of impairment before initiating any therapy. Till date, it has been done using the following tools; GMFCS, MACS and BFMF. [4][5][6] GMFCS scoring system was developed by Palsino and colleagues in 1997, later revised and expanded in 2007 to overcome its limitations. [4,9] GMFCS classifies CP into five levels; I, II, III, IV and V. The scores are ordinal and in the direction I (good) → V (bad) i.e. opposite to the direction of NFS which runs in direction 1 (bad) → 5 (good). These levels differ from each other based on functional limitations and the need of assistive technology type such as walkers, canes, crutches and wheeled mobility by the children. GMFCS scoring is mainly aimed at determining the level which can reflect the patients' current limitations and abilities. [8] GMFCS appears to be a broad classification symptom as the difference between Level I and Level II is not clearly recognizable. [8] In NFS, even the slightest improvement in the symptom is noted. Thus, evaluation of the patient's condition using NFS seems to be much more precise. The GMFCS scoring levels have also been described differently for children in several age ranges. [8] On the other hand, NFS scoring system is a single classification for the patients of all ages reducing the complexity of the evaluation system for physicians. GMFCS can only assess the patients aged upto. [10], whereas NFS can be used to assess the patients above this age limit.
As opposed to GMFCS which mainly assesses the ability of the patient to walk and stand, NFS is a broadened approach which can assess the ability to control head, balance the body, or walking. It can also assess the abilities related to sensory system such as feeling and controlling bladder and bowel excretion, hearing, and seeing and cognitive abilities like feeling hotness or coldness and understanding a "command". To further illustrate the use of NFS, let us take a hypothetical example of a patient with CP who is assessed with both the scoring systems (NFS and GMFCS), before and after receiving therapy. NFS grading per symptom is presented in Table  2. Let us assume that a patient with CP is placed in level 5 of GMFCS scoring system based on his After receiving the therapy, the patient is again evaluated with NFS and GMFCS scoring system. The total NFS score after the therapy is 120 and the GMFCS score is 1. ( Table 2) NFS score of 120 is calculated by adding the grades of individual symptoms to which the patient moved after the treatment. Improvement is noted in the symptoms including drooling, following commands, smiling, ability to recognize, eye contact, aggressiveness, ability to speak, ability to indicate, feeding, indicating for toilet, ability to do daily living skills, scoliosis lessened, defense mechanism developed, swallowing ability for solids, constipation frequency reduced, head and trunk control developed. The patient is also able to initiate rolling, able to crawl, developed I.T skills, able to sit, stand, walk, climb stairs and grip.
From this example, we can understand that GMFCS assesses the parameters broadly. In NFS, we graded parameters like commands, recognition, aggression, defense mechanism, constipation, ability to grip, breathing difficulty, feeding; which are not at all assessed individually in GMFCS. The other advantage of using NFS is that grades can be added or subtracted, thus can reveal even the slightest improvement in the patient. However, in GMFCS, the patient is graded to be in a single level that describes his/her present functional abilities. Our study poses a limitation in that NFS has only been used at our facility; however its wide use by other healthcare professionals in India and abroad is required to gather evidences signifying its use. The use of these numeric scores universally is recommended because they are pure numbers staying within the range of (0, 1), thus are compatible to all variables that distribute likewise including the probability distributions.
We have statistically validated the efficacy of human embryonic stem cells (hESCs) in patients with CP using NFS and results of this study will be presented in a different paper. Thus, NFS can be considered as a unique tool to assess the improvement in patients with CP. The NFS scoring system has only been used to evaluate the improvement in patients receiving hESC therapy. Further studies are needed to assess the improvement in CP patients receiving other treatments.