Abstract
The Moss Attention Rating Scale can be used to identify behavioral problems related to self-feeding independence, which can help occupational therapists to develop rehabilitation programs for their clients who have experienced a stroke.
Eating is an important activity of daily living (ADL) throughout life. Self-feeding can be assessed and modified to maximize independence (American Occupational Therapy Association [AOTA], 2017). It is one of the less difficult ADLs (Koyama et al., 2006), and independent self-feeding is one of the first goals to achieve in acute rehabilitation after stroke. Self-feeding independence is said to require fine motor control in hands, vision, and cognitive functions, including attention function (Mlinac and Feng, 2016; Swiech et al., 2020).
Approximately 80% of patients poststroke present some cognitive impairment (Jokinen et al., 2015). Attentional function is the basis of cognitive functions. It has been reported that approximately 80% of patients present with attention disorders after stroke (Spaccavento et al., 2019). Sohlberg and Mateer (1989) classified attention functions into four components: sustained, selective, alternating, and divided. Attention deficits can also inhibit ADL independence (Cumming et al., 2013). In this regard, it is important to determine the effect of attention deficits on ADLs, which appear frequently after stroke. However, matching neuropsychological testing of attentional function with ADL problems is often difficult (Parsons, 2015; Romero-Ayuso et al., 2021). Therefore, we hypothesized that the Moss Attention Rating Scale (MARS; Whyte et al., 2008), a behavioral observational rating scale of attentional function, would facilitate the identification of behavioral problems caused by attention deficits. Furthermore, because the MARS is an observational assessment, it can be used to evaluate even those who have difficulty with neuropsychological tests.
This study identified behavioral problems caused by attention deficits related to the level of independence in the process of bringing food to the mouth, using the MARS. To this end, we used self-feeding as defined by the AOTA (2014) and followed the classification of Sohlberg and Mateer (1989). We believe that our findings can aid in planning rehabilitation for self-feeding independence and in evaluating self-feeding.
Method
Study Design and Participants
This cross-sectional, single-center study was conducted at St. Marianna University Yokohama Seibu Hospital in Kanagawa, Japan. The study was approved by the hospital’s ethics committee and was conducted according to the tenets of the Declaration of Helsinki. Written informed consent was obtained from all patients.
The participants were patients who were admitted between December 2019 and December 2020 for the treatment of stroke and who underwent rehabilitation. The exclusion criteria were admission more than 1 wk after stroke onset, nasal tube feeding, tracheotomy, severe respiratory or cardiovascular diseases, orthopedic diseases such as fracture or amputation, apraxia, previous diagnosis of dementia, and inability to provide consent.
Outcome Measures and Assessments
The tests were administered by an occupational therapist who was familiar with these evaluation methods. All outcome measures were assessed within 1 wk before discharge. Neurological tests, neuropsychological tests, and the MARS were administered and evaluated during rehabilitation. Clinical characteristics, including age, gender, date of evaluation, diagnosis, and lesion, were also evaluated. Neurological tests included the Glasgow Coma Scale (GCS), motor paralysis, motor paralysis side, and grip strength of self-feeding use side. These tests were used to confirm whether there were any significant differences in physical function in terms of self-feeding independence. Neuropsychological tests included the Trail Making Test (TMT; Reitan, 1958) and the Symbol Digit Modalities Test (SDMT; Smith, 1982). These tests are commonly used in the assessment of attentional function. Because it is difficult to determine attention deficits on the basis of the MARS alone, we used these tests to determine whether there was a difference in the degree of self-feeding independence of stroke patients with and without attention deficits. The MARS was used as an observational rating scale. Attention deficit was defined as having abnormal TMT results or achieving an SDMT score below the chronological cutoff point. The presence of aphasia was determined by using the Standard Language Test of Aphasia. The presence or absence of unilateral spatial neglect (USN) was determined by observing ADLs when symptoms were suspected and conducting a line cancellation test.
The primary outcome measure was independence of self-feeding, as assessed by the FIM® subscore for eating. The secondary outcome measures included the evaluation of clinical characteristics, neurological tests, and neuropsychological tests.
Self-Feeding Ability
We assessed self-feeding ability in actual self-feeding situations by determining whether the patient could eat independently. Self-feeding independence was defined by the FIM subscore for eating. The participants were divided into two groups: those with an eating score of 6 or more (the independent group) and those with a score of less than 6 (the dependent group). All patients used chopsticks or spoons.
Trail Making Test
The TMT is composed of Part A and Part B (TMT-A and TMT-B, respectively), which assess mental flexibility, attention, and speed of a motor component (Lezak, 1995). This test is used worldwide as a test of attention function after stroke. The TMT-A requires sequential connections of numbered circles, which requires sustained and selective attention. In the TMT-B, participants circle numbers and letters, and they must connect the numbers and letters alternately. The TMT-B requires working memory, alternating attention, divided attention, and executive function in addition to sustained and selective attention functions. The TMT was standardized for healthy Japanese subjects in their 20s to 80s (Ishiai et al., 2019). Each part is rated as abnormal, boundary, or normal. The phase is judged comprehensively, using the time required for the test and the number of errors. In this study, abnormal TMT results were considered to indicate attention deficit.
Symbol Digit Modalities Test
The SDMT was used to assess divided attention and conversion attention. The test time was 90 s, during which the participants fill in specific symbols and corresponding numbers. The results are expressed as percentage of achievement ranging from 0% to 100%.
Moss Attention Rating Scale
The MARS was created by Whyte et al. (2008). Thereafter, the MARS was translated into Japanese by Sawamura et al. (2012). The MARS was developed for patients with traumatic brain injury but has been applied to patients with stroke and children with mild intellectual disability (Jacob et al., 2021; McCulloch et al., 2010). It consists of 22 items, and each item is scored from 1 to 5 (1 = definitely false; 2 = false, for the most part; 3 = sometimes true, sometimes false; 4 = true, for the most part; and 5 = definitely true). The MARS comprehensively assesses components of attentional function. The total raw MARS score is calculated as the sum of scores of 22 items and ranges from 22 to 110, with higher scores indicating better attention. In addition, there are scores for three-factor subitems: restlessness–distractibility, five items; initiation, three items; and consistent–sustained, three items. The total raw MARS score can be converted to a logit score ranging from 0 to 100. The three-factor scores and each item of the MARS were mainly used in this study. For flipped items, we used the scores after flipping.
Statistical Analysis
Patients were selected using propensity-score matching by age, presence or absence of paralysis, and total GCS to minimize selection bias among all patients. The chi-square test and Mann–Whitney U test were used as statistical methods to test for differences in MARS scores between the two groups. In addition, the effect size (r) of each variable was calculated. We performed statistical analysis using EZR software (Kanda, 2013), with statistical significance set at p < .05. The effect size was calculated using R (Version 4.2.2). The effect size was set as small for .10 ≤ r < .30, moderate for .30 ≤ r < .50, and large for .50 ≤ r (Cohen, 1988).
We performed power analysis using G*power 3.1.9.7 for Windows with a post hoc test (effect size = .50; Faul et al., 2007). The power of the test (1 − β) was <.8, indicating a low risk of Type 2 error (Cohen, 1988). The power was maintained, and the sample size was considered reasonable.
Results
In total, 96 patients (42 women and 54 men) participated in the study; 82 participants were independent in self-feeding, and 14 were dependent. Of the 14 patients in the dependent group, 2 had a FIM score of 2 points, 2 had a score of 3 points, 2 had a score of 4 points, and 8 had a score of 5 points. The clinical characteristics and neurological and neuropsychological findings of the participants are shown in Table 1.
Participants’ Background Factors and Evaluation Results
Note. CH = cerebral hemorrhage; CI = cerebral infarction; F = frontal; GCS = Glasgow Coma Scale; MARS = Moss Attention Rating Scale; P = posterior; SAH = subarachnoid hemorrhage.
The median age of the patients was 75.0 yr (range = 64.5–82.0). Sixty-five patients had a cerebral infarction, 14 had a cerebral hemorrhage, and 17 had a subarachnoid hemorrhage. The date of evaluation was a median of 3.0 days (range = 2.0–5.0) from admission. All patients were right-handed. Significant differences were observed in age, presence of surgery, and outcome destination between groups (p < .05). The median level of consciousness was 15.0 in the independent group and 14.0 in the dependent group for the total GCS score (p < .01). In total, 37 patients had motor paralysis (38.5%), with significantly more patients in the dependent group (p = .03). Grip strength was significantly lower in the dependent group (p < .01).
We performed propensity-score matching using age, total GCS score, and presence of motor paralysis to control for basic attributes and motor ability. Consequently, 12 pairs were selected (Table 2). No significant differences were noted in clinical characteristics or physical function such as age, gender, diagnosis, total GCS score, presence of motor paralysis, or grip strength between groups (p ≥ .05). No differences were observed in the rates of aphasia and USN between groups (p > .05).
Two-Group Comparison After Propensity-Score Matching
Note. Matching items were age, presence of motor paralysis, and GCS total. CH = cerebral hemorrhage; CI = cerebral infarction; F = frontal; GCS = Glasgow Coma Scale; MARS = Moss Attention Rating Scale; P = posterior; SAH = subarachnoid hemorrhage; SMDT = Symbol Digit Modalities Test.
Attention deficits were present in 23 of 24 patients (96%). Significant differences were noted between the two groups on the SDMT and TMT-A but not on the TMT-B. There were significant differences in total raw MARS, logit, and three-factor scores (p < .01). In addition, the effect sizes were large (r > .50). Among the three-factor scores, the effect size of the consistent–sustained attention score was large (r = .83). The three items that made up the consistent–sustained attention score were also significantly different between the two groups (p < .01), indicating a large effect size (r ≥ .75). Each item in the consistent–sustained attention score (e.g., “Performance is best early in the day or after a rest,” “Speed or accuracy deteriorates over several minutes on a task, but improves after a break,” “Performance of comparable activities is inconsistent from one day to the next”) was lower in the dependent group than in the independent group. Significant differences were noted between the two groups in 20 of the 22 MARS items (p < .05). The items with no significant differences were Item 1 (“is restless or fidgety when unoccupied”) and Item 21 (“performs better on tasks when directions are given slowly”; p ≥ .05).
Discussion
This study used the MARS, a behavioral observational measure of attention functions, to identify behavioral problems related to self-feeding independence by attention deficits. The MARS is an explanatory variable in ADL independence (Miyauchi et al., 2023). However, the association between self-feeding and MARS scores remains unclear. In addition, behavioral problems that are due to attention deficits in self-feeding are not clear. Self-feeding independence after stroke is associated with the ability to be discharged home (Sakurai et al., 2011). Attaining self-feeding independence from the acute stroke stage may increase the rate of discharge to home. The present study suggests that dependent self-feeding is related to a lack of sustained attention.
Self-feeding is the least difficult item among the FIM items (Koyama et al., 2006). Sustained attention is a lower order attentional function and is a base of attention (Langner & Eickhoff, 2013). In this regard, the degree of independence in self-feeding may be related to problems in basic sustained attentional function. However, differences between the two groups were found in most MARS items. It is possible that the sustained attentional function influenced behavioral problems in items other than consistent–sustained attention in the MARS, although USN and muscle strength were also considered to be related to self-feeding independence. In this study, after propensity-score matching, there were no significant differences between the two groups in clinical background factors, presence of motor paralysis, grip strength, presence of aphasia, or presence of USN. However, there were significant differences in tests of attentional function and MARS items. In this regard, we believe that the postmatching pairs used in this study reflected the influence of attentional function on self-feeding independence.
Two MARS items (Items 1 and 21) were not significantly different between the two groups. Item 1 (“is restless or fidgety when unoccupied”) is included in the restlessness–distractibility subitem. Item 21 (“performs better on tasks when directions are given slowly”) relates to auditory comprehension. There were no significant differences in these two items, suggesting that auditory comprehension and hyperactivity may not be a major issue for self-feeding independence. However, the effect size was moderate, and two of the MARS items (Items 1 and 21) are not entirely unrelated to self-feeding independence. Judging from the effect size, the 22 MARS items have more than a moderate effect and are considered useful as a behavioral observational rating scale of attentional functions necessary for self-feeding independence.
It is important to understand the behavioral problems of the MARS subitems of consistent–sustained attention listed in this study as part of the rehabilitation needed to achieve self-feeding independence. We believe that an approach that addresses these behavioral problems will lead to independence in self-feeding. For example, we believe that performing tasks that allow concentration for a certain period (e.g., a coloring book) or performing repetitive simple actions will help sustain movement. It may also be necessary to conduct rehabilitation in noisy surroundings. A comprehensive approach is essential, because cognitive impairments other than attention deficits, motor paralysis of the upper limbs, and muscle weakness must also be considered as preconditions.
This study has several limitations. First, the study sample size was small, because the assessment was conducted in a single center, possibly limiting the generalizability of the study findings. Second, the association between independence of self-feeding and change in the MARS over time was unclear in this cross-sectional study. Third, the dependent group included patients with various amounts of assistance, and the behavioral problems of attention deficits according to the amount of assistance have not been clarified. Finally, only the MARS, a behavioral observational rating scale for attention deficits, was used, and behavioral problems caused by other cognitive dysfunctions could not be identified. Future longitudinal studies are needed to clarify the relationship between degree of independence in self-feeding and changes in the MARS score. In addition, other behavioral observational rating scales should be used to identify more multifaceted behavioral problems.
Implications for Occupational Therapy Practice
The findings of this study have the following implications for occupational therapy practice. The MARS could be used to identify behavioral problems related to self-feeding independence that are caused by attention deficits. The level of independence in self-feeding is thought to be particularly related to sustained attentional function. When implementing occupational therapy aimed at self-feeding independence, a focus on sustained attentional function would be preferable.
Conclusion
Behavioral problems related to self-feeding independence that are caused by attention deficits include the inability for sustained attention. Our results suggest that sustained concentration during self-feeding is necessary for self-feeding independence. Rehabilitation focused on sustained attention might be desirable for self-feeding independence.
Footnotes
Acknowledgments
We thank the patients who participated in the study and the staff members of the St. Marianna University Yokohama Seibu Hospital for their assistance with the data.