Identifying barriers and problems of physical environment in older adults’ homes: An ergonomic approach

Abstract

BACKGROUND:

The main purpose of ergonomics is environment adaptation to humans, and the root cause of the barriers and problems of the older adults is the mismatch between the home environment and their limitations.

OBJECTIVE:

The present study aimed to identify and explain physical environment barriers and problems among older adults’ homes in Yazd, Iran.

METHODS:

This qualitative study was conducted as conventional content analysis. In total, 53 participants including 36 older adults and 17 caregivers were enrolled in the study. The participants were selected using convenience and purposive sampling methods, while the data collection method was a semi-structured interview. The interviews were recorded and transcribed, and then analyzed using MAXQDA11 software.

RESULTS:

Following data analysis, 268 initial codes were extracted. They were classified into three major categories and 31 sub categories. The main categories are “barriers and problems associated with older adults’ sensory limitations,” “barriers and problems associated with older adults’ motor limitations,” and “barriers and problems associated with older adults’ cognitive limitations.”

CONCLUSIONS:

Although the data collected from the older adults and their caregivers are in many cases similar, caregivers can provide reasons for the barriers and problems as well as solutions better than the older adults. The data also indicate that most of the problems and barriers are related to motor limitations.

Keywords

Qualitative study older adults barriers home environment ergonomic

1 Introduction

Older adults prefer to spend more time at home [1]; they feel more secure in their own environment, as well as with their family and community [2]. The home environment promotes older adults’ autonomy, health, and independence [3], which are critical components of successful aging. The desire of older adults to remain at home with their family and community is referred to as “aging in place” [4]. However, the primary issue is that the standard home environment is designed more for the needs and abilities of young than for older adults, and older adults’ needs cannot be easily met due to disability and limitations [5]. Disability and limitation result from a mismatch between an individual’s abilities and environmental requirements [6].

As people age, their abilities deteriorate [7]. Aging is associated with a loss of physical, motor, and cognitive abilities [8], including mobility, flexibility, agility, vision [9, 10], perception, and memory [9]. This degradation can affect the performance and work activities of the older adults [11 –13]. Decreased abilities of the older adults increase their dependence on others [14, 15].

The root cause of barriers and problems of the older adults in the home environment is the mismatch between the home environment and the abilities and limitations of the older adults. Therefore, lack of attention to the physical limitations of the older adults in designing the physical environment of homes can lead to the emergence of barriers and problems of the older adults in their homes, which is due to the mismatch between the home environment and the abilities of the older adults. This is also the reason for using the ergonomic approach.

Ergonomics is one of the sciences that may be relevant in this context. One of the primary goals of this science is to adapt humans to their environment [16]. Ergonomics and human factors engineering are fields of study that examine human capabilities and limitations through the lens of human characteristics, structures, and processes involved in interacting with product design and the environment [17]. Thus, environmental adaptation to humans is possible through proper environmental design and consideration of human capabilities. Unfortunately, the degree of ergonomic adaptation between the environment and the physical condition of older adults is negligible in their living environments [18].

Numerous studies have been conducted on the issues confronting older adults; however, there are only a few empirical studies on the physical environment of older adults’ homes [19]. The majority of research on the physical environment of older adults has concentrated on fall prevention. Additionally, these studies focused primarily on people with disabilities, and there are few studies on the general population of older adults [20]. One of the research challenges in studying older adults’ housing is the inherent diversity of homes and their residents; thus, additional research is needed to understand better the challenges older adults face in their living environment [21].

Iran is one of the Asian countries experiencing rapid population aging [22]. Estimates of the WHO indicate that by 2030, the older adults’ population in Iran from 6.5%to 17.5%[23]. However, a population study in Iran has indicated a rapid population aging [24]. It is predicted that by 2050, one in four Iranians will be older adults [25]. Naturally, the aging process and its consequences should be viewed as one of Iran’s future challenges [23]. Additionally, building, maintaining, and renting new houses is prohibitively expensive in Iran, forcing older adults to live in traditional, dilapidated neighbourhoods [26]. In other words, Iranian structures are unsuitable and inaccessible for older adults citizens [27]. Sadly, in Iran, responsible organizations’ care programs do not adapt and reconstruct older adults’ homes to meet international standards [28].

The study took place in Yazd, the capital and largest city in the Province of Yazd, located in central Iran. According to the 2016 census, the Province’s population was 750,769 (75.10%urban and 24.90%rural), of which, 103,450 were 60 years or older [29]. Given that Yazd, apart from having a modern architectural texture, is one of the few cities in Iran where people still live in their traditional homes, this issue has resulted in the city’s diverse architectural texture. Thus, the purpose of this qualitative study is to identify and explain the barriers and problems encountered by older adults in their physical environments from both the perspective of the older adults and their caregivers.

2 Methods

2.1 Participants and procedures

The qualitative method was used in this study because it is an effective way to describe real-life experiences by giving them meaning [30]. Additionally, the conventional content analysis method was used to analyze the data and explain the barriers and problems associated with the physical environment of the older adults’ home from an inclusive design perspective. This method comprehensively describes a phenomenon and is well-suited for examining people’s perspectives on a particular subject. Participants in this study included 36 older adults and 17 older adult caregivers chosen through convenience and purposive sampling.

This sampling method is one of the common methods in qualitative studies on the older adults due to the limitations of collecting data from the older adults. In this study, in order to design the interview framework, first the older adults and caregivers who were easier to access were interviewed. In purposeful sampling, the older adults rich in information were interviewed, including those with physical disabilities, as well as caregivers with lots of work experience in this field who were constantly caring for the older adults; moreover, the type of home was paid attention. The research setting of this study was the homes of the older adults residing in Yazd, Iran in 2020.

2.2 Inclusion and exclusion criteria

The inclusion criteria were information-rich cases in which participants were chosen from a group of older adults aged 60 and over who resided in their homes in Yazd city. The study excluded older adults living in nursing homes with a significant disability or completely reliant on others. The inclusion criteria for caregivers of older adults were caregivers who provided services to older adults in their homes.

2.3 Data collection

When interviews cease to contain novel information or perspectives, theoretical saturation occurs [31]. In qualitative research, the number of samples is constantly changing, and the researcher continues sampling until a new idea occurs to the individual [32]. The location and timing of the interviews and other processes associated with the content recording were determined at the interviewees’ discretion. Semi-structured interviews were used to elicit data. The principal researcher conducted all interviews. According to the preferences of the older adults and their caregivers, the interview was conducted in places, such as the older adults’ homes, parks, and etc.

General questions were designed as an interview guide which were open-ended with interpretive answers and the subjects’ answers led the process. The number of questions varied according to the type of disability of the older adults, the type of daily activities of the older adults, and the type of home. After asking general questions, the researcher would ask specific questions, so that according to the type of daily activities of the older adults in different parts of the house, cases related to barriers and problems of the home environment were questioned from the perspective of the older adults and their caregivers. Each interview lasted between 15 and 30 minutes, and more extended interviews were conducted in two stages. All interviews were conducted in a quiet location, and sampling was continued until information saturation was reached, indicating that participants provided no additional information [33].

2.4 Analytical procedures

The data were analyzed using the conventional content analysis method. Following each interview, the researchers meticulously typed their contents word for word and read them several times to ensure consistency and accuracy. Familiarization with data was immersed by transcribing the interviews and then reading and rereading the transcripts or listing to the recordings. The interviews served as the analysis unit in this study, and the semantic units were sentences or paragraphs from the interview texts. Generating initial codes was begun to identify the preliminary codes that were the aspects of the data that appeared to be interesting and meaningful. After that, each keyword or sentence was assigned a code. The first level of coding was accomplished in this section by identifying and forming the codes; the second level involved grouping the same initial codes; and finally, the major categories were extracted. To ensure that all data were classified accurately, the researcher referred back to the interview transcripts and extracted codes. MAXQDA11 software was used to analyze and code the interviews, and finally, the categories, subcategories, and codes derived from the interviews were formed.

2.5 Data trustworthiness

Credibility, transferability, trust, and verifiability were used to determine the validity of the data [34]. Researchers attempted to guarantee the validity by careful selection of the qualified participants and also close, frequent, and long participation of the volunteers during data analysis and using the experts’ ideas in different stages of the study. They also attempted to increase the study credibility as much as possible by preserving the documents through the investigation and providing the possibility of reviewing the stages of investigation by others. The review method was used to obtain consensus agreements on data transmission capability. Additionally, the researcher distributed the results to experts in this field who provided positive or negative feedback based on the researcher’s interpretation. Maximum variation sampling also contributed to the data’s transferability and acceptability [35].

2.6 Ethical considerations

The ethics committee at Tabriz University of Medical Sciences, Iran, approved the study protocol (IR.TBZMED.REC.1398.517). Before starting the interview, the interviewer introduced herself to the participants and fully explained the purpose and procedure of the study including use of the audio recorder to record the interview. The subjects gave verbal consent followed by written consent, and the method and objectives were explained verbally and in writing. Additionally, they signed an informed consent form for the interview to be recorded. Moreover, the participants were reassured about confidentiality and anonymity of their information. Individuals were informed via an informed consent based on the Helsinki Declaration.

3 Results

The participants included older adults with a mean age of 73.4 years (61–94 years) of both genders (12 males and 24 females) and 12 female and 5 male caregivers with a mean age of 44.2 years (24–58 years). The participants’ characteristics are shown in Table 1.

Table 1
Characteristics of participants

Characteristics Older adults Caregivers

(N = 36) (N = 17)

Mean age (Years) 73.4 42

Age (Years)

20–29 2

30–39 5

40–49 6

50–59 4

60–69 9

70–79 16

80–89 8

90–99 3

Range 61–94 24–58

Sex

Male 12 12

Female 24 5

Education

Less than college 22 11

College 14 6

Characteristics	Older adults	Caregivers
Mean age (Years)	73.4	42
Age (Years)
20–29		2
30–39		5
40–49		6
50–59		4
60–69	9
70–79	16
80–89	8
90–99	3
Range	61–94	24–58
Sex
Male	12	12
Female	24	5
Education
Less than college	22	11
College	14	6

Following the data analysis in this study, 268 initial codes were extracted and categorized into three major categories and 31 subcategories. Some of the extracted codes are: Narrow entrance doors, High dishwasher height, Improper dimensions of stairs, etc.

“Barriers and problems associated with sensory limitations in older adults,” “Barriers and problems associated with motor limitations in older adults,” and “Barriers and problems associated with cognitive limitations in older adults” were the three major categories. (Table 2)

Table 2

The results of qualitative analysis of the interviews

Theme	Main category	Subcategory
Physical environment problems in the older adults housing	Barriers and problems related to sensory limitations	–Inadequate ambient lighting
		–Inadequate natural light due to a lack of windows
		–Hard to see light switches in dark environments
		–Low volume of the doorbell
		–Absence of video door phone or light alarms
		–Inadequacy of cooling and heating systems
		–Lack of hot water in the kitchen and toilets
	Barriers and problems related to mobility limitations	–Inadequate dimensions of doors, entrances and passageways
		–Existence of uneven surfaces in the walkways
		–Lack of sufficient space in the bathroom and toilet
		–Unsuitable sinks, lavatories, and stoves for people with disabilities
		–Long access paths
		–The number of stairs in access paths and their unsuitable dimensions
		–Wrong place for light switches and sockets
		–Inadequate access to door and window handles
		–Inadequate access to shelves, upper cupboards, and cabinets
		–Inadequate access to the sink, lavatory, and dish drainer
		–Inadequate type of door handles and faucets
		–Sharp and non-beveled edges
		–Lack of grab bars, especially in bathrooms and toilets
		–Inadequate guarding near heights, particularly adjacent to stairs, ramps, and gardens
		–Smooth and slippery floor surfaces
		–The existence of uneven access paths
		–Doors, cupboards, and windows do not open and close easily
		–Absence of WC’s
	Barriers and problems related to cognitive limitations	–Unapparent surface differences due to color
		–Inappropriate color of surfaces
		–Unsuitable arrangement of objects (misplacing things
		–The complexity of working with appliances
		–Noise pollution in the environment
		–Unreadability of utility gauges, keys, and buttons

3.1 Barriers and problems related to sensory limitations in the older adults

3.1.1 Inadequate ambient lighting

The analytical study of the older adults’ and caregivers’ interviews revealed that ambient light levels could directly affect the appearance of objects and obstacles in areas where older adults walk. As a result, lighting in the home environment should be adjusted to accommodate the vision limitations of older adults.

One of the caregivers for older adults stated:

“Because older adults’ people frequently struggle to see their surroundings properly due to poor vision, having a bright room is more beneficial. The majority of them complain about the room’s darkness and how they need to move closer to see clearly.”

3.1.2 Inadequate natural light due to a lack of windows

The data obtained from the interviewees showed that the presence of windows in the building that provides natural light has several advantages over artificial light and is critical for improving the moods of older adults who are lonely.

A 76-year-old woman stated:

“It would be better if I had a larger window in my room, because this window is too small, and there is no sunlight during the day, leaving my room dark, whereas the other room is the same size and is dark during the day”

Additionally, one of the caregivers stated:

“As people age, they experience a sense of well-being when they sit near a window and gaze out. If they have a view of trees in the yard, their mood improves”

3.1.3 Hard to see light switches in dark environments

The results indicated that older adults with visual impairments have difficulty finding the light switch and may fall or bump into objects, injuring themselves, particularly in dark environments.

A 73-year-old man stated

“I once awoke in the middle of the night and needed to use the bathroom, so I went to find and turn on the light switch. My foot collided with one of the table legs, and I sustained an injury that took six months to heal due to my diabetes”

Another caregiver stated:

“Typically, older adults require a light switch and a power outlet nearby, as they have poor vision and must be able to locate them easily, particularly at night when it is dark, and they have difficulty locating the light switch”

3.1.4 Low volume of the doorbell

The interview analysis revealed that the low volume of the doorbell might be difficult for older adults to detect due to their hearing impairments. On the other hand, due to the sensitivity of their auditory system, an increased volume of the doorbell may irritate older adults.

An 81-year-old woman stated:

“Both my husband and I have hearing loss. Occasionally, someone rings the doorbell, and we miss it. My children have their keys, and if they forget them and ring the doorbell, they may find themselves waiting behind the closed door.”

According to the son of one of the older adults caring for his mother:

“If I’m not with my mother at the time and someone rings the doorbell, she will not hear it. I asked my brother to contact someone to adjust the doorbell’s volume so that it would be louder but not so loud that she would jump when it rang.”

3.1.5 Absence of video door phone or light alarms

The results indicated that older adults who have severe hearing loss or deafness and cannot hear the doorbell ring require a video entry system or light alarms. They should be installed in an appropriate location in the house so that older adults can see the system illuminate or the light alarms activate and notice the person at the door.

A 76-year-old man stated:

“I have hearing loss and am unable to hear without my hearing aids. I used to be able to tell when someone was at the door because the video entry system would illuminate when the doorbell was rung, but it stopped working a few months ago and required repair.”

3.1.6 Inadequacy of cooling and heating systems

The results revealed that the older adults are more sensitive to cold and heat; thus, providing an adequate cooling and heating system can help them feel comfortable.

A 68-year-old woman stated:

“Our home is cold in the winter, and we must sit near the heater to stay warm. It’s cold throughout the house, and the kitchen is also freezing. My daughter’s house is completely toasty due to the radiators. In the summer, because we lack a good air conditioner, our home becomes oppressively hot, and we are constantly sweating.”

Another caregiver stated:

“I constantly reminded my father not to sit too close to the heater, but on one occasion, he did, and the heater burned his toes, and due to his diabetes, the wound refused to heal and grew worse until he was forced to have his ankle amputated.”

3.1.7 Lack of hot water in the kitchen and toilets

The findings showed that one of the older adults’ primary complaints about their homes is a lack of hot water in the kitchen and toilets. It reduces the individual’s quality of life by increasing their sensitivity to the subject.

A 69-year-old woman stated:

“The kitchen and toilet are both without hot water. Because the shower is the only source of hot water, I become irritated when I wash dishes or go to the bathroom, especially in the winter.”

3.2 Barriers and problems related to motor limitations in the older adults

3.2.1 Inadequate dimensions of doors, entrances, and corridors

Based on the results, it can be concluded that one of the issues in older adults’ homes is the inadequacy of the dimensions of the room, toilet, and corridor entrance doors. The narrow width of the doors can be detrimental to older adults who rely on walkers or wheelchairs to get around indoors.

One of the caregivers stated:

“Due to a mobility issue, we purchased him a walker, which has made him much more comfortable and enables him to manage his personal affairs; however, due to the narrowness of the corridor’s exit door, he is unable to access the yard. It would have been preferable if the door had been wider, as his walker is currently unable to pass through.”

3.2.2 Existence of uneven surfaces in the walkways

The analysis of interviews with older adults and their caregivers revealed that uneven walkway surfaces, particularly in the bathroom, toilet, and bedroom, can increase the risk of falls and fatigue in older adults. Additionally, it means they have limited mobility with wheelchairs and walkers.

One of the caregivers stated:

“Unfortunately, no one cares about the older adults. The majority of houses in which I worked had a bathroom entrance with stairs. That is not an issue for a healthy person, but for older adults who frequently experience leg pain or rely on walkers and wheelchairs, going to the bathroom with stairs presents a challenge and requires assistance.”

3.2.3 Lack of sufficient space in the bathroom and toilet

The results indicated that one of the issues facing older adults is a lack of space in the bathroom and toilet, particularly for those who use walkers or wheelchairs. Additionally, when older adults require assistance, space constraints can create several complications.

A 74-year-old woman stated:

“Our bathroom is so small that it is barely functional. I constantly collide with the door and the wall.”

According to another caregiver:

“Often, older homes have small toilets and bathrooms that are barely large enough for one person. If they require assistance, the second person will be unable to enter at all.”

3.2.4 Unsuitable sinks, lavatories, and stoves for people with disabilities

The analysis of the interviews showed that that older adults were unable to stand for an extended period due to musculoskeletal problems and leg pain. They frequently have difficulty standing for an extended time during dishwashing or cooking. As a result, a wheelchair- or handicap-accessible kitchen is necessary for this group of people.

A 76-year-old woman stated:

“When I want to cook food and have to stand for an extended period, standing in front of the stove hurts my legs. Additionally, I must rest my hand on the sink while washing the dishes, or else I am forced to take frequent breaks and am unable to complete the task without interruption.”

3.2.5 Long access paths

The interview analysis revealed that one of the primary issues confronting older adults living in large homes is the length of access paths to various house areas, such as bathrooms, kitchens, bedrooms, building entrances, and parking.

An 82-year-old man stated:

“Because our toilet is in the yard, it stresses me out whenever I need to go, as I have to stop a few times to sit or lean against the wall on the way.”

3.2.6 The number of stairs in access paths and their unsuitable dimensions

The study’s data analysis revealed that one of the study’s findings is that one of the access issues and limitations in older adults’ homes is the long staircase in their access paths. As a result, older adults often have difficulty overcoming barriers due to their motor limitations, mainly if the stairs are located in high-traffic areas of the house, such as the toilet, bathroom, bedroom, or entrance.

One of the caregivers stated:

“The majority of older adults suffer from leg pain, and today, every house has a few steps leading up to the entrance, and the majority of them also have steps leading up to the bathroom or kitchen, and no one considers how older adults are supposed to climb these stairs.”

3.2.7 Wrong place for light switches and sockets

The analysis of the results shows that switches and sockets should be located so that older adults can use them with minimal movement.

A 75-year-old man stated:

“The electrical wiring in older homes is not up to code, unlike the wiring in our current home. To turn on the lights, you must move to the opposite side of the room.”

3.2.8 Inadequate access to door and window handles

The analysis of interviews indicated that one of the issues confronting older adults in their homes is the inadequate height of door and window handles, which restricts older adults’ ability to open and close doors and windows.

One of the caregivers stated:

“Older adults have difficulty reaching door and window handles due to their insufficient height.”

3.2.9 Inadequate access to shelves, upper cupboards, and cabinets

According to an analysis of conversations, older adults have difficulty reaching shelves, upper cupboards, and cabinets due to their limited range of motion and height loss associated with aging.

An 80-year-old woman stated:

“If I require assistance with something from the upper cabinets, I must summon assistance. My hands are insufficiently strong to reach.”

Additionally, one of the caregivers stated:

“The older adults frequently have difficulty raising their hands to reach items on shelves, upper cupboards, and cabinets.”

3.2.10 Inadequate access to the sink, lavatory, and dish drainer

Analyses of the interviews showed non-compliance with appropriate height and width standards in sinks makes them challenging to use. Additionally, they have difficulty using the drain drainer due to the height at which it is located.

A 73-year-old woman stated:

“Our bathroom faucet is extremely difficult to turn. Occasionally, I am unable to turn it in either direction. Lever faucets are more convenient to operate.”

3.2.11 Inadequate type of door handles and faucets

According to the interviews, older adults have difficulty using round doorknobs and prefer lever handles due to a decline in physical strength. Additionally, lever faucets are more suited to older adults; they can be opened and closed more quickly, and older adults frequently struggle with round faucets.

A 75-year-old man stated:

“Our bathroom faucet is extremely difficult to turn. Occasionally, I am unable to turn it in either direction. Lever faucets are more convenient to operate.”

3.2.12 Sharp and non-beveled edges

Analyses of interviews with older adults and their caregivers revealed that older adults are more likely to collide with the edges of walls, doors, and cabinets due to postural imbalance, resulting in injury.

An 81-year-old woman stated:

“My wife once slipped in the bathroom, struck her head on the sharp edge of the wall, and sustained an injury. We rushed her to the doctor, where she received five stitches.”

3.2.13 Lack of grab bars, especially in bathrooms and toilets

The results indicated that older adults need to grab bars to assist them in remaining safe due to decreased physical strength when standing or climbing stairs. As a result, grab bars, particularly in toilets, bathrooms, stairwells, and ramps for older adults, are critical.

A 78-year-old man stated:

“In general, standing is difficult for me. When I go to the toilet, I have to pull myself up using the plumbing.”

An 80-year-old woman also stated:

“There is a step on the balcony, so I must climb using the handrails.”

3.2.14 Inadequate guarding near heights, particularly adjacent to stairs, ramps, and gardens

According to the interview analysis, older adults are more likely to fall due to imbalance. As a result, adequate guarding is required, particularly near stairs, ramps, and heights.

One of the caregivers stated:

“Because older adults frequently lose their balance when confronted with heights or slopes, they are at risk of falling; therefore, appropriate guarding is critical where there is a risk of falling.”

3.2.15 Smooth and slippery floor surfaces

Analyses of interviews with older adults and their caregivers revealed that the smooth and polished floor surfaces of passageways in homes, particularly bathrooms, toilets, and kitchens, where the floor is occasionally wet, can result in injuries or falls. As a result, it is recommended to use a floor surface that is sufficiently rough to prevent slips and falls.

A 73-year-old woman stated:

“Our bathroom’s ceramic floor is extremely smooth. When I enter, I must exercise extreme caution. So far, I’ve slipped and fallen several times.”

3.2.16 The existence of uneven access paths

The results of the interviews indicated that one factor contributing to older adults falling in their homes is the presence of uneven passageways. Therefore, it is critical to eliminate uneven surfaces, particularly in access paths such as the kitchen, bathroom, toilet, bedroom, entrance, and yard, to prevent older adults from falling.

A 76-year-old woman stated:

“Each room has a door frame. My feet have become stuck, and I’ve slipped several times, injuring myself. Because the edges of several of the mosaics are raised, I have to be cautious not to get my feet stuck.”

Additionally, one of the caregivers also stated:

“The majority of older homes have door frames, and older adults frequently become trapped because they are unable to raise their legs while walking. Those who use walkers or wheelchairs face additional difficulties.”

3.2.17 Doors, cupboards, and windows do not open and close easily

According to an analysis of conversations with older adults and their caregivers, certain doors and windows in older homes frequently become stuck due to wear and tear and must be forced open or shut. Due to their motor limitations, older adults typically have difficulty opening and closing them.

One of the caregivers stated:

“The doors in mud-brick houses frequently become stuck in the frame due to their age, and they must be opened and shut with difficulty. This is a significant concern for senior citizens.”

3.2.18 Absence of WC’s

The interview analysis revealed that older adults have difficulty using traditional squatting toilets due to mobility limitations, resulting in knee pain, and typically prefer to use toilets designed to sit.

According to an 84-year-old gentleman:

“When I need to use the restroom, I am forced to squat on the pan due to my knee pain.”

3.3 Barriers and problems related to cognitive limitations in the older adults

3.3.1 Unapparent surface differences due to color

The analysis of the interviews showed that older adults might have difficulty distinguishing between levels with no difference in color. This factor may contribute to them losing their balance and falling.

According to one of the caregivers:

“I have to be very careful with him. He can’t get down the stairs by himself. He is unable to detect the stairs properly and has been fallen several times in the past.”

3.3.2 Inappropriate color of surfaces

The analysis of conversations revealed that selecting appropriate colors for surfaces can positively affect the mood of older adults. Additionally, the optimal use of contrasting colors can assist older adults in identifying objects and locations.

According to one of the caregivers:

“It is preferable to paint the doors and walls a different color to make it easier for older adults to identify the door. In general, using distinct colors can assist older adults in identifying objects.”

3.3.3 Unsuitable arrangement of objects (misplacing things)

The results indicated that older adults frequently forget where objects are due to memory problems and forgetfulness. Therefore, if the arrangement allows older adults to see the majority of their belongings, it can aid in preventing forgetfulness and assisting them in locating their belongings more quickly.

According to one of the caregivers:</para>

“I’m required to place everything in front of them, so they don’t have to search for it. They struggle with memory and forgetfulness.”

3.3.4 The complexity of working with appliances

The findings showed that the simpler the appliances, the easier they are to use for older adults. Generally, they do not favor the use of complicated appliances.

According to a 76-year-old woman:

“If the water heater goes out, I am unable to turn it back on. My children taught me several times, but I was still confused. If it goes out, I must call them to come and turn it back on.”

Additionally, one of the caregivers stated:

“In general, older adults struggle with new technologies as appliances become complex. They would rather use used equipment than new equipment.”

3.3.5 Noise pollution in the environment

According to the analysis of interviews, older adults are more sensitive to noise pollution than other age groups, and being in these environments can disrupt their mental balance.

According to one of the children of the older adults who were caring for his parents:

“My parents’ sensitivity has increased as they’ve grown older. They constantly complain about the noise created by cars and motorcycles passing through the alley and children playing in the yard.”

3.3.6 Unreadability of utility gauges, keys, and buttons

The results revealed that older adults struggle to read the information on gauges, buttons, and keys due to cognitive limitations. The required information should be presented in a more readable format.

According to a 76-year-old woman:

“I’m unsure how to adjust the water heater’s temperature. I’m not sure how far to turn it in to get hot water.”

4 Discussion

The purpose of this study was to identify and explain the barriers and problems encountered by older adults in their homes in Yazd, Iran and this was the first qualitative study in this field in Iran, according to the literature review. The items were classified into three broad categories: barriers and problems associated with sensory, motor, and cognitive limitations, as the root cause of many of the problems encountered by older adults in their homes is their sensory, motor, and cognitive limitations. This classification can aid in comprehending and recognizing environmental needs within these constraints, which is consistent with the fundamentals of ergonomics’ study of human capabilities and limitations and the features, structures, and processes relating to human interaction with the environment.

4.1 Barriers and problems related to sensory limitations in the older adults

The barriers and problems encountered by older adults in their homes’ physical environment, which were classified as “barriers and problems associated with sensory limitations” and subcategories such as “inadequate ambient lighting, lack of windows to provide adequate natural light, among others,” are rooted in the older adults’ sensory limitations.

Perception is primarily determined by the function of the five senses, which include sight, hearing, touch, smell, and taste. However, when interacting with the environment, sight and hearing account for most interactions [36]. Aging significantly impairs the senses of sight and hearing, which are the two primary senses [37]. Changes in recognizing, interpreting, and responding to visual and auditory information can impair daily functioning [17]. According to research, the degree of adaptation in the eye significantly decreases with age [38]. Visual acuity typically declines by about 50%between the ages of 60 and 80, impairing a person’s interaction with the environment and objects [37].

Assuming that employees have an average age of 40 years, a 50-year-old requires twice the amount of light to perform the same visual function as a 60-year-old, and a 60-year-old requires five times the amount of light. In other words, vision loss in older adults can be compensated for by increasing light in the environment [38]. Additionally, to compensate for vision loss in older adults living alone, lighting in their homes must be double that of an ordinary environment [39].

Additionally, one of the requirements for residential homes for older adults is installing windows in rooms and common areas. Windows are necessary for visual communication as well as providing natural light [39]. On the other hand, studies have shown that natural light can improve older adults’ sleep and that daytime light exposure can help them sleep better [40, 41].

Since older adults are less likely to leave their homes due to physical limitations, vitamin D obtained through sunlight must be supplemented [42]. Inadequate lighting is one of the leading causes of accidents among older adults living in their homes [43]. By creating inappropriate shadows, the level of ambient lighting can create the illusion of stairs or uneven surfaces for older adults, posing potential dangers [39]. Visual impairments can also make it difficult for older adults to locate light switches, resulting in accidents. As a result, it is recommended that older adults use light switches with indicators to see them in dark environments easily. On the other hand, older adults adjust to light changes more slowly than younger age groups; as a result, it is recommended that older adults gradually adjust to new environments [39].

Another issue for older adults is that they have a misconception about lighting inadequacy and frequently become accustomed to insufficient lighting [18].

According to studies, not only the eye, as the primary sensory organ, suffers a severe decline in function with age, but we also observe significant changes in the auditory sense with age [38]. Hearing loss, which is more prevalent than visual impairment in older adults over 60, is the third most common disability after arthritis and hypertension [44]. Hearing loss has also been linked to an increased risk of falling [45] and cognitive decline [46]. Auditory sensitivity typically decreases to about 20 decibels between the ages of 60 and 80, impairing a person’s interaction with the environment and objects [37]. As a result, audible alarms in homes should be chosen in accordance with their hearing limitations. For example, the doorbell volume should be loud enough for older adults to recognize the sound, or video alarms, such as video entry phones or light alarms, should be used instead of audio systems for deaf older adults.

Older people are also susceptible to temperature changes and dry air. Unfavorable temperature conditions can significantly impact their physical and mental health, and older adults are incapable of rapidly adapting to cold and heat [42]. As a result, it is necessary to provide suitable temperature conditions for older adults’ thermal comfort [39].

4.2 Barriers and problems related to motor limitations in the older adults

The barriers and problems encountered by older adults in their homes’ physical environment, which were classified as “barriers and problems associated with motor limitations” and subcategories of “inadequate dimensions of doors, entrances, and access paths, uneven surfaces in walkways, and a lack of adequate space in the bathroom and toilet, among others,” are rooted in motor limitations.

Motor disabilities are the most prevalent type of disability among senior citizens [47]. Older adults are typically more susceptible to disorders and changes in motor function than younger adults [48]. In older adults, these changes include musculoskeletal and motor changes of varying degrees. Additionally, aging impairs physical and motor abilities, including access, flexibility, and skill [9, 10]. In old age, muscle mass decreases due to a decrease in the number and size of muscle fibers. Atrophy occurs more frequently in muscles responsible for maintaining physical and motor status and is more prevalent in the lower limbs than in the upper limbs [48]. Additionally, muscle contraction occurs more frequently in type II fibers (which are responsible for rapid contractions) than in type I fibers (which are responsible for strength contractions), which prevent rapid muscle contractions [49].

As a result of the issues mentioned above, older adults cannot walk long distances without stopping, and building construction plans should take this into account by shortening access paths, ideally without stairs or surface differences. In the case of longer paths, rest areas for sitting and relaxing must be provided. Additionally, older adults are unable to stand for an extended time due to muscle weakness. As a result, facilities for working sitting positions should be considered, such as customizing the sink, stove, and toilet seat to accommodate a sitting position or installing a shower chair in the bathroom to cater to older adults’ needs.

Another common issue with aging is a loss of handgrip strength [50]. This issue results in older adults having difficulty performing tasks that require handgrip strength, such as opening and closing the refrigerator door and door handles in rooms and bathrooms [14]. Studies have shown that between the ages of 60 and 80, handgrip strength typically decreases by about 30%, impairing older adults’ interaction with their environment and objects [37]. As a result, lever handles are preferred over round doorknobs for doors and windows. Additionally, lever faucets are more suited to older adults, as they are easier to turn.

Aging can also result in changes to an older adult’s physical dimensions. As a result, older adults face additional challenges with facility design, as anthropometric data on older adults is typically overlooked when contractors design such facilities [51]. For example, designing spaces and entrances for older adults, particularly those who use wheelchairs or walkers, necessitates increased door and entrance dimensions. Additionally, studies have shown that joint range of motion decreases with age [52], resulting in decreased access range in older adults. Therefore, when designing shelves, upper cupboards, cabinets, and access to lavatories, sinks, dish drainers, and faucets, older adults’ access restrictions should be considered.

Another common disorder among older adults is impaired balance function. Numerous researchers believe that as people age and their organs’ functions change, the balance mechanism also changes. In other words, as they age and their sensory systems, motor control, muscle strength, and power deteriorate, older adults develop poor postural control and balance [53]. A balance disorder significantly increases the risk of falling [54].

Falls among older adults are a significant factor in their early hospitalization and ongoing care, resulting in an early decline in daily activities and increased support services [55]. Among the known risk factors, the home environment significantly impacts older adults’ falls in the community [56]. As a result, many falls occur at home; older adults spend more time at home and perform most of their daily activities at home [57].

Additionally, any obstruction in passageways or smooth and polished surfaces can result in falls or accidents in older adults who lack postural control and balance. As a result, designers and officials must mitigate these events by removing or modifying the barriers mentioned above and considering older adults’ motor limitations and balance impairment. On the other hand, given the inevitability of events caused by balance disorders and falls in older adults, measures to mitigate the severity of accidents, such as beveling the edges of walls and surfaces, installing appropriate guarding near precipices, and installing auxiliary equipment such as grab bars in toilets and bathrooms or adjacent to the stairs, must be considered.

4.3 Barriers and problems related to cognitive limitations in the older adults

The barriers and problems encountered by older adults in their homes’ physical environment, which were classified as “barriers and problems associated with cognitive limitations” and subcategories such as “imperceptibility of surface differences due to the same color, inappropriate color of surfaces, and unsuitable arrangement of objects (misplacing things), among others,” are rooted in the motor limitations of older adults.

Cognitive abilities are a significant predictor of the amount of assistance and support received by older adults. Natural cognitive status is contingent upon the proper operation of the entire brain system [58]. Cognitive disorders are one of the most prevalent and progressive conditions associated with aging. Even with natural aging, most people experience impairments in cognitive functions such as processing speed, attention, and memory [59]. These changes may impair people’s ability to process feedback from their environment and objects [60]; for example, the presence of equipment or outdoor noises may irritate older adults.

According to epidemiological studies, approximately 5%of people aged 60 and over have severe cognitive impairment. After age 65, the prevalence of this disorder doubles every five years, reaching more than 40%in the population aged 80 and over [58]. Aging results in degenerative diseases and changes in various parts of the body, including the brain, resulting in cognitive impairment and dysfunction in older adults. These disorders range in severity and affect a diverse group of older adults [58].

Between the ages of 60 and 80, short-term memory typically declines by about 14%, impairing a person’s interaction with the environment and objects [37]. As a result, older adults face additional difficulties in the home environment due to memory impairments; they frequently forget where they put things. As a result, when designing houses, the arrangement of objects should be as visible as possible to enable older adults to locate them more quickly.

Moreover, aging can impair vision, contrast sensitivity, and the ability to recognize colors, resulting in difficulties with reading and recognizing letters and symbols and the accuracy with which buttons and keys are pressed [17]. These cognitive disorders can impair an older adult’s ability to distinguish between different surfaces and surfaces of the same color. Thus, using contrasting colors on the edges of uneven surfaces enables older adults to identify them quickly. Additionally, appliance gauges, keys, and buttons should be large enough for older adults to read. According to researchers, severe cognitive disorders can impair performance in daily activities [61]. In other words, cognitive functioning in older adults can serve as a predictor of daily functioning [58].

Given that most people build or purchase a home during their youth or middle age, they adapt building design criteria to their current abilities and are less likely to meet old age needs. These homes are not adapted to the sensory, motor, or cognitive limitations of older adults. As a result, any design feature can become a barrier or a source of contention for older adults, increasing their reliance on others. Additionally, redesigning residential homes is typically prohibitively expensive for older adults. As a result, they rarely adhere to adaptation measures and recommendations for their homes unless absolutely necessary.

Aging in place is a continuous dynamic interaction between the individual and the environment, in which both the individual and the environment change [62]. When environmental needs exceed an individual’s capabilities, or when an individual’s capabilities exceed environmental needs, an incompatible situation occurs. As a result, older adults’ physical, mental, and cognitive limitations can make it difficult to meet environmental needs. As with an individual’s dynamic nature, the environment can change in response to resident demands [21].

5 Conclusion

Given the limitations of collecting data from the older adults, using the opinions of caregivers can play an important role in identifying barriers and problems in the physical environment of homes. Although the data collected from the older adults and their caregivers are in many cases similar, caregivers can provide reasons for the barriers and problems as well as solutions better than the older adults. Also, the data obtained from both groups indicate that the most problems and barriers are related to motor limitations, which can be justified due to the higher prevalence of motor limitations in the older adults.

The results of the present study indicated that the older adults’ barriers and problems in their home environment in many cases are due to the mismatch between the physical design of the home and the older adults’ needs and this issue can cause trouble and also increase their dependence on others.

Therefore, the findings of this study, along with those of similar studies, can assist legislators and officials in revising laws and regulations, ensuring their proper implementation, and incorporating these criteria into building design to the maximum extent possible. In other words, older adults must live in homes that require minimal adaptation and modification in accordance with the concept of inclusive design. These findings can also be used to develop and revise home standards to meet the needs of older adults.

Application of new design approaches, such as inclusive design, allows designers to design products and services in order to meet the needs of a larger group of users regardless of their age and ability [63, 64].

For the first time in Iran, a qualitative study examining the barriers and problems faced by older adults in their physical environments of homes was conducted. This study examined both the older adults and their caregivers’ perspectives, which can be considered one of the study’s strengths.

The study limitations were as follows: inclusion of the older adults’ homes in Yazd not the other cities, the cross-sectional nature of the data, the older adults’ tendency to underestimate the problems [65], and the older adults forgetting some problems.

Accordingly, it is recommended to conduct studies on a larger statistical population from other geographical areas with different cultures and lifestyles to determine the role of culture and lifestyle and the type of architecture in the older adults’ problems. On the other hand, given that the present study focused on urban houses, it is recommended to examine rural homes in future studies.

One of the study’s limitations was that the older adults’ general mental picture of their housing situation was inaccurate. On the other hand, another significant limitation regarding the housing status of older adults was their proclivity to underestimate access issues and environmental risk factors. older adults in general do not perceive how environmental barriers might affect everyday activity until the problems are real [66]. As a result, future studies should incorporate the perspectives of geriatricians, designers, and builders. Finally, given the diversity of architecture and design of dwelling houses across regions, it is necessary to conduct future research in other cities, primarily rural areas.

Footnotes

Acknowledgment

This study is part of a Ph.D. dissertation on ergonomics approved by the Tabriz University of Medical Sciences, Iran, which was financially supported by the Vice-Chancellor for Research. The authors are indebted to university officials, older adults, and their caregivers who cooperated in this study.

Conflict of interest

The authors have no conflict of interest to declare.

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