Background
Cognitive dysfunctions in memory, thinking, problem-solving, and emotional problems severely interfere with the daily lives of people with dementia [
1]. Among them, the dietary function is essential to daily life [
2]. People who suffer from earlier stages of dementia may experience executive dysfunction [
3]. This primarily affects their planning and decision-making related to nutritional intakes, such as shopping, food preparation, food choices, and intake amount [
3‐
5]. As the disease progress, they may gradually experience eating and feeding problems or other mealtime difficulties including the inability to concentrate on eating, inability to place food into the mouth, food falling from the mouth, failure at spoon-feeding [
6,
7], difficulty in chewing and swallowing, or altered eating behaviours during mealtime [
5,
8,
9] due to apraxia (inability to use utensils) and agnosia (inability to recognise food) [
10].
About half the people with dementia have lost their self-feeding abilities within eight years post-diagnosis [
11]. Many studies have found that 38.6% [
12] and 36% of people with dementia have eating difficulties or other problems [
13] that contribute to the progression of dementia. Eating problems make mealtime slow and result in many adverse health outcomes for people with dementia, including weight loss, aspiration, infection, dehydration, being at risk for malnutrition, and death [
5,
9,
14‐
16]. Dietary and nutritional problems related to cognitive disabilities negatively impact a patient’s life during different stages of dementia and cause caregivers distress.
Most people with dementia live at home alone or are cared for by informal caregivers, typically their spouses or other family members [
5,
17]. Therefore, accurate and regular assessment or screening of dietary functioning is recommended to detect nutritional problems as early as possible [
5,
6,
8,
14]. Aselage [
14] conducted an integrative review of 12 instruments divided into three categories, including eating behaviours (Level of Eating Independence Scale, LEI; Eating Behaviour Scale, EBS), feeding behaviours (Feeding Abilities Assessment, FAA; Edinburgh Feeding Questionnaire, EdFED-Q; Self-feeding Assessment Tool of Osborn and Marshall; McGill Ingestive Skills Assessment, MISA; Feeding Behaviours Inventory, FBI; Feeding Traceline Technique, FTLT; Feeding Dependency Scale; The Aversive Feeding Behaviour Inventory, AFBI) and mealtime behaviours (Meal Assistance Screening tool, MAST; Structured Meal Observation, SMO). However, only three instruments (EdFED-Q, FAA, and FTLT) were psychometrically evaluated. Moreover, AFBI, EdFED-Q, and EBS were used to assess the nutritional status of moderate to severe people with dementia in long-term care facilities. These instruments typically focus on the nutritional situation. They often include questions on BMI, weight loss, reduced dietary intake, and disease stress for people with dementia who live in care facilities. However, people with dementia in institutions do not need to prepare their own meals. In addition, these instruments are not simple or short enough for informal caregivers to administer at home, i.e., none of these tools have been specifically designed and validated for home-dwelling persons with dementia. Furthermore, few suitable screening tools have been applied to executive and self-eating functions in the home-dwelling of people with dementia [
5]. Therefore, developing a user-friendly instrument to assess dietary functioning that covers both executive and self-eating functions for home-dwelling people with dementia is necessary. Such an instrument will help family caregivers identify issues with dietary functioning earlier and provide appropriate assistance and interventions to help this population. This study’s purpose was to develop and evaluate the psychometric properties of the Dietary Functional Assessment Scale (DFAS) for use in home-dwelling people with dementia.
Discussion
This study’s newly developed DFAS is primarily used by family caregivers to examine the dietary functioning of home-dwelling people with dementia. This study’s findings verify that the DFAS is a user-friendly instrument with good validity and reliability. The results suggest that this tool is a reliable means by which dietary functions among home-dwelling people with dementia can be measured. A 10-item scale was initially generated through a literature review and based on the clinical experience of the research team. After evaluation and recommendations from experts, two unsuitable items were deleted, and one item was added, where the final scale comprised nine items. Acceptable content validity of greater than 0.80, according to Waltz, and Strickland [
20], was obtained. Through an item analysis and EFA, two additional items were deleted that could not meet the criteria. Factors that emerged in these EFA appeared relatively stable, well-defined, and conceptually coherent, with two factors explaining 56.94% of the variance. Thus, the final DFAS includes seven items and two factors: self-eating
ability and
dietary executive function. The CFA analysis conducted using Sample 2 also indicated that the scale category goodness-of-fit indices were appropriate based on Hays and Revicki’s [
32] recommendation that reliabilities exceeding 0.70 are considered acceptable.
The first factor,
self-eating ability, refers to the ability to eat. This involves essential dietary-related functions in daily life, such as eating habits, putting food into the mouth, using utensils, healthy food preferences, and adequate dietary intake during the eating process. Maintaining a patient’s eating ability is a significant concern for family caregivers. Among the items related to habits and food preferences influenced by cognitive decline corresponding to the results of other studies [
10], changes in the eating behaviours of people with dementia lead family caregivers to be concerned about their emotional status. Although in the CFA, item 3 (eats an appropriate amount at meals), there was a slightly lower factor loading on this factor, it was still higher than 0.3. Some eating behaviour assessment tools used for people with dementia consider intake amount to be directly associated with functions and nutritional status. Thus, item 3 was retained [
6,
14].
The second factor,
dietary executive functions, is an essential aspect of dietary functioning, which indicates planning, meal preparation, and making decisions at mealtime. Impairments in executive functions can affect the performance of instrumental daily life activities and worsen the quality of life [
33]. Executive functions have already been indicated to deteriorate prematurely in people with dementia, even starting from mild cognitive impairment [
34]; this may be the earliest symptom that accompanies cognitive decline, further affecting the ability to prepare meals and eat [
35,
36]. Patients in advanced stages of dementia are often institutionalised due to increasing dependence. Therefore, most previously developed assessment instruments have been concerned about care needs, such as assisting with feeding, feeding behaviours, choking, swallowing impairment during mealtime, and nutritional status. It would be worthwhile to examine the impairment in executive functions of home-dwelling people in the early stages of dementia.
This study’s findings indicate that the total DFAS score had a moderate negative correlation (
r = -0.528,
p < 0.01) with the MNA score, demonstrating that poor dietary functioning is associated with poor nutritional status. This result is similar to the findings of previous studies on care facilities that have found impairments in “eating ability” and “meal preparation” were significantly related to malnutrition [
37‐
40].
The present study proposes the AUC approach to identify the optimal cut-off point value through ROC analysis. The results showed poor AUC and specificity values for the cut-off score of 11 points. However, the results indicate satisfactory AUC and sensitivity/specificity values for a cut-off score of 13 points. Therefore, we recommend this cut-off point to detect poor dietary functioning in home-dwelling people with dementia.
Measurements developed to assess concepts that are different but similar to the concept of mealtime, feeding, and eating of people with dementia have been developed and used to measure mealtime difficulties since the 1990s [
14]. However, most prior measurements have addressed moderately to advanced stages of dementia residing in long-term care facilities and hospital settings. Furthermore, most tools lack good psychometric properties. Among them, only the EdFED-Q [
7] is a validated tool [
37], yet, the EdFED-Q is an observational tool for use in moderate to advanced stages of dementia in long-term care facilities, not a screening tool for early detection for home-dwelling people with dementia.
We acknowledge this study’s following limitations. First, the small size and convenience sampling nature of the sample. As such, the findings might not reflect the general population, which can be a potential limitation of this study. Secondly, we did not provide construal-related measurements to measure the same target. Last, some psychometric properties are missing such as the test-retest reliability. In addition to improve the psychometric properties of the tool through the COSMIN indicators in future research, the developed tool can be extensively used in communities for early detection of nutritional problems for people with dementia.
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