Expected Attributes to Design Sleeping Facilities for the Elderly

based on the Potential Stakeholders Point of View

Elty Sarvia

, Elizabeth Wianto

2,3 b

, Erwin Ardianto Halim

and Elvira Natalia

Bachelor Program in Industrial Engineering, Universitas Kristen Maranatha, Bandung, Indonesia

Industrial Design Department, National Cheng Kung University, Tainan, Taiwan

Bachelor Program in Visual Communication Design, Universitas Kristen Maranatha, Bandung, Indonesia

Bachelor Program in Interior Design, Universitas Kristen Maranatha, Bandung, Indonesia

elizabeth.wianto@art.maranatha.edu, maresanatalia@gmail.com

Keywords: Design Aspect, Elderly, Ergonomics, Kano, Sleeping Facilities, Mann-Whitney-U.

Abstract: Adequate sleep to rest is a beneficial activity to maintain health. Therefore, the facilities that support this

activity need to be appropriately designed. In accordance with the fact that after entering retirement age, the

elderly are often supported by their adult children, so most of the time, the elderly's life's necessities will be

handled by their child(ren). Hence, this study aims to analyze the perceptions of the two main stakeholders,

namely: potential target buyers (children) and target users (parents) of sleeping facilities that can differ from

one another related to the expected value. This study explores expected design attributes to achieve elderly's

good sleep quality using in-depth interviews with the selected participants and get 22 valid and reliable

attributes by sharing 70 pairs of children-parents using non-parametric Mann Whitney-U. Unexpectedly, these

two different generations perceived the proposed attributes as similar to one another. Further analysis using

the Kano method found that two attributes need to be fulfilled by design: (1) sliding the bed; (2) the lower

area of the bed should be cleaned easily. These two attributes are then discussed from the perspective of

Indonesian natural resource usage and habits.

1 INTRODUCTION

Indonesia, as the fourth most populous country,

already entering an aging population since 2015 with

its elderly population more than 7% and consistently

increased to 9.92% (26.86 million people) in 2020

(McDonald, 2014). The prediction of its elderly

population will become nearly 20% in 2045 (Sari et

al., 2020). Significant changes in demographic

proportion caused this developing country has an

urgent need to set their point of view on how the

society regularly works. In general, the elderly will be

divide into potential and non-potential elderly (Act of

the Republic of Indonesia on welfare of the elderly

(Undang-undang Republik Indonesia tentang

kesejahteraan lanjut usia), 1998) and with a tendency

of declining health condition once people get older,

https://orcid.org/0000-0003-3708-8723

https://orcid.org/0000-0002-0859-2659

https://orcid.org/0000-0003-3642-7404

https://orcid.org/0000-0002-2668-598X

then this demographic changing will directly add the

burden of the productive community. Nevertheless,

World Health Organization proposed the healthy

aging concept which emphasizes for the elderly to

live a long and healthy life despite of free of disease

condition which might not be feasible for older

people.

This study is a continuation from the previous

study which shown that the anthropometric data for

the elderly has a correlation with their living

condition: community-dwelling or retirement home

(Sarvia, Wianto, Yudiantyo, Apriyani, & Costa,

2021). Even though becoming old is not a disease,

but once the individual reach maturity state, their

physical ability inevitably will deteriorate (Castillo-

Rodríguez, Onetti-Onetti, Mendes, & Chinchilla-

Minguet, 2020).

Sarvia, E., Wianto, E., Halim, E. and Natalia, E.

Expected Attributes to Design Sleeping Facilities for the Elderly based on the Potential Stakeholders Point of View.

DOI: 10.5220/0010749600003113

In Proceedings of the 1st International Conference on Emerging Issues in Technology, Engineering and Science (ICE-TES 2021), pages 265-270

ISBN: 978-989-758-601-9

265

Sleeping pattern for the elderly will change as

older people tend to sleep earlier but also wake

earlier, more frequently during the night and

experiencing fragmented sleep. Some of these

changes directly relate to sleeping disorders such as

snoring and obstructive sleep apnea (Wolkove,

Elkholy, Baltzan, & Palayew, 2007). Other sleeping-

related activities also indicating that low sleeping

quality can be associated with poor cognitive

performance of the elderly (Blackwell et al., 2006;

Nebes, Buysse, Halligan, Houck, & Monk, 2009).

Nevertheless, quality of sleep constitutes many

factors, and will optimize the functional ability and

quality of life (Bliwise, 1993).

Considering the urgencies to support the good

quality of sleep, then this study is trying to explore

the attributes to design adequate sleeping facilities.

Most of the times, large-size furniture including a bed

has a long time of use, sometimes furniture with

specific material can be passed down to generations

as they excel in quality and become a family

heirloom. However, due to the change of needs for

the elderly while sleeping, as well as to reduce

another undesirable occasion such as falls (Sahota et

al., 2014), then changing sleeping facilities while the

elderly still in a potential state is arguably beneficial.

By using the preference of potential buyers and

potential users (older people), then discussion related

to the design of sleeping facilities for the elderly will

be discussed and formulated. The target user for these

specific mediated tools will be the older person which

still categorized as potential elderly; therefore, the

design will be distinguished with the hospital or long-

term care bed.

2 METHODS

This study is an action research considering the

potential user to improve the related existing product.

Data collection method used in this study divided into

two steps. The first step is to explore the potential

attributes preferred by the elderly, caregiver, or the

children of the elderly. The second step is to validate

the emerged attributes from the first step. Both of the

steps were using purposive and snowball sampling

structure as part of a non-probability sampling

technique with inclusion criteria to the Indonesian

adult with an experience in taking care of the elderly

or has the possibilities as the potential buyer for the

designed sleeping facilities.

For the first step, we gathered data collection by:

(1) in-depth interview related to the sleeping facilities

of the elderly, like/ dislike aspects of their own bed,

their activities before, while wake up during the night

and once wake up in the morning. (2) focus group

discussion related to the preferred function of

sleeping activities including its surroundings.

Combining those two data collection techniques

was needed in this study. Along the way, the in-depth

interview resulted in not too clear attributes,

especially from the elderly who in general stated that

they are already satisfied with their own sleeping

facilities. Therefore, from the in-depth interview, it is

found out that the answers are already saturated

(Braun & Clarke, 2019). Hence, the saturation of the

data was our argument to conduct different technique

to explore the attributes.

All of the attributes emerged from step one, then

converted into functional (positive statement) and

dysfunctional (negative statement) following the

Kano model. After converted into a functional and

dysfunctional statement, in this study name as

variables. Each variable will follow the Kano method

as the selected approach to analyse attribute of

features to design products or services. The Kano

model is applied to identified customer needs and

calculate customer satisfaction that helps to prioritize

the importance of service qualities that can increase

customer satisfaction in health service (Gupta &

Srivastava, 2011). The identification of urgencies by

customer requirements should then convert into Kano

model using five expressions of: like, must be,

neutral, live with/ neutral and dislike. However, for

this study, we modified this model into 5 five steps of

the Likert scale to enable inferential statistical

analysis.

For the second step, the questionnaire was given

in the form of functional-dysfunctional statements

which were divided into three aspects: (1) mattress

(14 variables); (2) divan/ bed (40 variables); and (3)

surroundings of sleeping facilities (10 variables).

Total 64 variables, divided into every 32 attributes

were shared with paired children and elderly parents.

The purpose of pairing the answers was to understand

whether any discrepancies of preferred variables to

define good sleeping facilities for the elderly

Other additional questions to add clustered group

once needed also asked in form of: (1) sex; (2)

education level; (3) appropriate price for elderly’s

single bed.

2.1 Participants

Participants in the first step of data collection were

gathered by means of qualitative information. In this

step, seven people were invited to join in-depth

interview (four elderly and three caregiver/ adult who

ICE-TES 2021 - International Conference on Emerging Issues in Technology, Engineering, and Science

266

has experience in taking care of the elderly) and for

the additional data, focus group discussion were held

separately. Each group discussion consists of 7

people (4 male, 3 female); 4 people (1 male, 3

female); 6 people (1 male, 5 female); and 4 people (4

female) not including at least one researcher as the

moderator.

The second step data collected by sharing to 70

paired adult children with their parent(s) using an

online questionnaire. Between February and April

2021, 70 paired Indonesian adults with their elderly

parent(s) were given their consent to be recruited in

this study. The age range for overall participants were

21-74 years old, with two majorities of age range 39-

47 years old for 34% and 48-56 years old for 26%.

The youngest elderly is with the age of 60 years old.

The majority of the participants is women for 61%.

Two majorities of education level were having

bachelor’s degree and master’s degree for 48% and

21% respectively. The validity and reliability of each

attribute explain in point 2.2.

2.2 Valid and Reliable Attributes

After the data was collected from 70 pairs of parent

and child respondents, the validities of 64 variables

(32 attributes) were tested and it was found that there

were 10 invalid variables, so that the 10 invalid

variables were filtered again to find their

functional/dysfunctional partners to be dropped along

with these invalid variables. Those 22 retained

attributes (44 variables) then consider valid to be

further usage (Sugiyono, 2017). Thereafter the

process continues with a reliability test to make sure

measurement reliability. The Alpha Cronbach obtains

0.875 and is believed as having high consistency to

measures adequate sleeping facilities aspects for the

elderly.

3 RESULTS AND DISCUSSION

Results and discussion of this study divided into point

3.1 for Mann-Whitney U-Test and 3.2 for

classification using Kano method.

3.1 Mann-Whitney U Test

The pairs of children's and parent's answers to 44

variables (22 attributes) that passed the validity and

reliability tests were tested on the distribution form of

the answers obtained. The results of the data

normality test using Kolmogorov Smirnov on the

variable answers of the child and parent participants

showed that the data were not normally distributed (p

<0.05), so the proof of the hypothesis would be

followed by the Mann Whitney test. The results of the

Mann Whitney test on 44 variables (22 attributes)

show that there is no difference in opinion between

the child's partner (as a potential buyer) and the

parents/elderly (as a potential user) on the variables

that are important in the design of bed facilities, so it

can be concluded that the opinion parent is similar

with their child regarding sleeping facilities for the

elderly.

The results of Mann-Whitney U Test for the

attributes shows that all of the null hypothesis should

be retained. Here is the point of significance of each

attribute, by their aspects, as follows:

1. Four valid attributes for mattress were proven for

K1_2, K1_5 with the Sig. 0.179 and 0.841

respectively.

2. Eighteen valid attributes for bed/ divan proven for

R1_3, R1_4, R1_5, R1_6, R1_7, R1_8, R1_9,

R1_10, R1_11, R1_12, R1_13, R1_14, R1_15,

R1_16, R1_17, R1_18, R1_19, R1_20 with the

Sig. 0.776, 0.525, 0.693, 0.887, 0.474, 0.054,

0.189, 0.844, 0.521, 0.961, 0.689, 0.320, 0.967,

0.810, 0.505, 0.600, 0.456, 0.618 respectively

3. Four valid attributes for surroundings were

proved for L1_4 and L1_5 with the Sig. 0.405 and

0.561 respectively.

3.2 Classification of the Attributes

using Kano Method

The output of the functional and dysfunctional

variable statements will be calculated according to the

Kano classification which is divided into 6 (six)

classifications according to the exposure in Table 1.

Table 1: Kano decision matrix, modified from original form

(Berger, Blauth, & Boger, 1993)

Customer

Requirement

Dysfunctional

(ne

ative) statement

L M N A D

Functional

(positive)

statement

L Q At At At O

M RI I I M

N RI I I M

A RI I I M

D R R R R Q

Note:

L: Like A: Acceptable N: No feeling/ Neutral

M: Must Be D: Do not like At: Attractive

R: Reverse Q: Questionable

O: One Dimensional I: Indifference

Expected Attributes to Design Sleeping Facilities for the Elderly based on the Potential Stakeholders Point of View

267

Kano classification was determined by Blauth’s

formula (Ginting, Siregar, & Ginting, 2015) with the

following algorithm:

1. (O+At+M) > (I+R+Q) with the result O/A/M

selected by maximum value,

2. (O+At+M) < (I+R+Q), with the result I/R/Q

selected by maximum value,

3. (O+At+M) = (I+R+Q), with the result O/A/

M/I/R/Q.

Attribute classification has the purpose to divide

the strong attributes to count in the next process

according to the potential customers (elderly as the

user, and adult children as the potential buyer). The

retained attribute will be signed with M (Must Be), At

(Attractive), and O (One Dimensional) while the set

aside attribute is the one with sign I (Indifference), R

(Reverse), and Q (Questionable).

Attributes R1_12 (The bed needs to be easy to

move) and R1_13 (The bed needs to be easy to clean

underneath were the only two attributes categories as

One Dimensional (O) while attributes K1_2 (The

mattress is made of hard foam material) categories as

Reverse (R). The other 19 attributes categories as

Indifferent (I) thus will not be considered or discussed

further in this study because of the inability of the

attributes to influence potential customer satisfaction

(Gupta & Srivastava, 2012).

Attribute coded with K1_2 (The mattress is made

of hard foam material) proven categorized as a

Reverse attribute. This class can be explained as the

specific requirement for the quality should not appear

on the product otherwise the satisfaction will be less.

The mattress is a lying mat used while sleeping. A

comfortable mattress is an essential element in a good

night's sleep, one of which is using an excellent and

comfortable type of mattress that can improve

sleeping quality, fitness, relieve pain and sleepiness

during the day Individuals differ as to the degree of

mattress firmness that is associated with their best

sleep. The best sleep quality is usually influenced by

actigraphic motion, the number of awakenings, and

how long the user awake during the night (Hogan,

Edinger, Bieler, & Krystal, 2011).

However, this attribute is considered inconsistent

and doubtful because the perception of the hardness

of the mattresses is perceived differently, because in

one of not validated variables, we also offer the

statement with ‘soft foam material’ and proven to be

not valid. Thus, the statement related to the mattress

hardness should be directly tried by the participants,

thus required further definition and explanation.

Table 2: Attributes tabulation of Kano’s classification.

Code Attributes Q At O I M R OAtM IRQ Class.

K1_2 The mattress is made of hard foam material 26 11 3 38 1 61 15 125 R

K1_5 The mattress is equipped with anti-decubitus mats (dead

tissue conditions due to sitting / sleeping too long)

6 33 29 55 10 7 72 68 I

R1_3 The bed is equipped with a headboard at the head 2 16 38 68 5 11 59 81 I

R1_4 The upper bed can be tilted (for an upright/reclining

position, etc.)

2 32 24 70 3 9 59 81 I

R1_5 The lower bunk is tiltable (to raise the legs) 3 28 20 76 4 9 52 88 I

R1_6 The bed is equipped with a barrier on either side 4 20 16 73 6 21 42 98 I

R1_7 The bed is equipped with a handle that makes it easy to get

out of bed

2 29 30 53 12 14 71 69 I

R1_8 The barrier on the right and left of the bed is made of a

hard material when held

6 16 24 72 10 12 50 90 I

R1_9 The barrier on the right and left side of the bed is made of

cold material when touched (example: iron)

5 9 10 78 4 34 23 117 I

R1_10 Light bed 3 21 21 75 5 15 47 93 I

R1_11 Heavy bed 3 11 7 88 4 27 22 118 I

R1_12 The bed needs to be easy to move 4 28 46 44 13 5 87 53 O

R1_13 The bed needs to be easy to clean underneath 3 267319172 116 24 O

R1_14 Bed with voice command for specific commands (example:

raise down to lower position)

6 20 10 83 8 13 38 102 I

R1_15 The bed is equipped with a storage area for sanitary and

medical equipment (water hoses, soap, towels, tensimeter,

oxygen cylinders, necessities, etc.)

6 23 22 67 10 12 55 85 I

R1_16 The bed is equipped with a walking stic

6 24 12 79 8 11 44 96 I

R1_17 The bed is equipped with an electricity socke

2 1822744 20 44 96 I

R1_18 The bed is equipped with heaters 4 25 11 77 10 13 46 94 I

R1_19 Near the bed there is a bell/alarm that is easily accessible

from a lying position

4 18 36 65 11 6 65 75 I

R1_20 There is a panic/emergency button 5 25 28 62 13 7 66 74 I

L1_4 The bed is equipped with a table for eating in be

2 3218694 15 54 86 I

L1_5 There is an area to use the potty 3 23 22 65 10 17 55 85 I

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Attribute coded with R1_12: The bed needs to be

easy to move, one of two attributes that need to be

fulfilled by the furniture and interior designer. The

importance of moving the bed could emerge due to

various reasons, including changing the arrangement

or layout of furniture in the bedroom due to changes

in the way of life (e.g., death of the spouse causing

the space in the bed is often adapted or adjusted to

current conditions). Additional furniture in the room

(e.g., there are other items or storage for storing

things), or adjustments due to replacement of old

furniture for various reasons and these changes result

in changes to the layout of the room because the size

of new furniture does not match the size of the old

furniture. Another reason why the bed finally needs

to be moved easily can also occur because the needs

to clean the house thoroughly frequently (e.g., for

Chinese Indonesian people, annually cleaning the

house, including the bed right before Chinese New

Year).

Attribute coded with R1_13: The bed needs to be

easy to clean underneath, which is the other attribute

that needs to be fulfilled by furniture designers or

service providers to consumers (elderly). The bed

needs to be easy to clean underneath for comfort

reasons to achieve hygienic reasons. A bed that is

easy to clean underneath should, in other ways can be

fulfilled when the bed is easily moved. However, not

every bedroom's layout has the flexibility to move

furniture when cleaning the room. The need or

urgency for cleaning the room is directly related to

the material used to traditionally fill the mattress,

namely kapok (Java Cotton). Mattress filling

materials nowadays have gradually changed by foam,

spring bed, latex, and even using a special contoured

material to treat the patient's decubitus condition.

However, for the elderly that most of whom were

born in 1960 and earlier, it is still common to use

kapok as a filler for mattresses, pillows, and bolsters.

The standard preference to use kapok as the

material used also correlates with Indonesia's

condition as one of the largest kapok producers in the

world (Mardiyati, Raden Reza Rizkiansyah, Steven

Steven, Arif Basuki, & Suratman., 2016) which

allows easy access or use of this material.

Unfortunately, kapok, which is a natural material, has

a weakness, namely, it produces visible dust particles

and needs to be cleaned periodically because of the

potential as a place for mites to develop. As for

cleaning the cotton mattress, occasionally, the

mattress will be lay under the sun and turned over.

The method, although frequently done to prevent

house dust mites, will expel even more dust particles

into the air. The activity of laying and turning the

mattress also results in a thinner mattress design so

that it is lighter to lift when compared to a spring bed

type.

Once associated with bed designs that need to be

easily cleaned at the bottom, the bed design for cotton

mattresses is often different from bed designs for

spring or latex mattresses. Bed designs for cotton

mattresses in Indonesia generally use a solid wood

(e.g., teak wood) or iron frame that is painted or

layered, the bottom of the bed often has space, and by

calculating the thickness of the mattress that ranges

from 8 to 15 cm, the area at the bottom of the bed is

relatively easy to clean using traditional cleaning

tools. The habit of cleaning the bottom of the bed

regularly done by the elderly has changed gradually

with the trend of optimizing free space underneath to

make it more useful because there is a reduction in a

room or house with higher property prices. However,

both of the attributes concern as the additional value

for elderly’s sleeping facilities, not must have one.

4 CONCLUSIONS

This study shows that the two generations still have

the same perception about providing the best sleeping

facilities for the elderly. There is no difference in

perceptions of the attributes that have been previously

explored in this study. However, not all attributes

influence user satisfaction.

The two attributes that are still desirable in the

design of sleeping facilities for the elderly related to

the habits of society in Indonesia can be said to be

unique and still need to be maintained well to the

procurement for furniture or interior designers

because the increasing number of elderly populations

will lead to higher demand. Even though, in general,

the use of furniture has a long service life, it cannot

be denied that there are changes in the way of life of

the elderly in their old age, causing the need for a

readjustment of interior design both in the bedroom

in general, as well as in the creation of the bed in

particular.

Furthermore, paying attention to the good habits

of the elderly who have been fostered since they were

young and combining them with technology,

materials, and designs is alleged to be maintained the

quality of life of the elderly in their old age.

For further research, this study will be followed

up with recommendations for the design of sleeping

facilities for potential older adults by taking into

account the attributes obtained and the two main

attributes, namely the ease of the bed that is easily

Expected Attributes to Design Sleeping Facilities for the Elderly based on the Potential Stakeholders Point of View

269

shifted and the bottom part of which is easy to clean

which most affects user satisfaction.

ACKNOWLEDGEMENTS

The authors are grateful for the partial support from

Universitas Kristen Maranatha, with internal research

scheme funding academic year 2021 and to all of the

participants who willing to support us with valid and

reliable data.

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