Abstract
Furniture manufacturers’ response to the demographic challenge of aging nations is an important issue. The number of seniors is rising worldwide. The aging process often results in multiple health implications, including weaker mobility, decrease in muscle mass, and change in anthropometrical dimensions of the human body. Thus, the furniture offered should be adjusted to the needs of an increasing group of senior customers. To identify seniors’ preferences in relation to characteristics of sitting furniture, international surveys with 627 respondents aged 60+ years were conducted in Poland, Germany, Denmark, Finland, Latvia, and Lithuania. The implementation of this data in the design process may result in creation of the market offer meeting seniors’ needs. Design and functionality features were examined to provide guidance for senior-friendly development of furniture for sitting. Among the most important findings is the clear preference of having an armchair with the high backrest reaching above the head, a chair with armrests and an upholstered backrest and seat. Furthermore, respondents paid attention to the durability of furniture, stain resistance of upholstery, and adaptation of the furniture to the user’s dimensions, e.g., having influence on the height and depth of the seat before the purchase.
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Comparative Study on Design and Functionality Requirements for Senior-friendly Furniture for Sitting
Beata Fabisiak,a,* Anna Jankowska,b Robert Kłos,a Joan Knudsen,c Sari Merilampi,d and Elina Priedulena e
Furniture manufacturers’ response to the demographic challenge of aging nations is an important issue. The number of seniors is rising worldwide. The aging process often results in multiple health implications, including weaker mobility, decrease in muscle mass, and change in anthropometrical dimensions of the human body. Thus, the furniture offered should be adjusted to the needs of an increasing group of senior customers. To identify seniors’ preferences in relation to characteristics of sitting furniture, international surveys with 627 respondents aged 60+ years were conducted in Poland, Germany, Denmark, Finland, Latvia, and Lithuania. The implementation of this data in the design process may result in creation of the market offer meeting seniors’ needs. Design and functionality features were examined to provide guidance for senior-friendly development of furniture for sitting. Among the most important findings is the clear preference of having an armchair with the high backrest reaching above the head, a chair with armrests and an upholstered backrest and seat. Furthermore, respondents paid attention to the durability of furniture, stain resistance of upholstery, and adaptation of the furniture to the user’s dimensions, e.g., having influence on the height and depth of the seat before the purchase.
Keywords: Furniture for sitting; Design; Functionality; Senior-friendly; Age-generations; Baltic Sea region countries
Contact information: Poznan University of Life Sciences, Wojska Polskiego Street 38/42, 60-627 Poznan, Poland; a: Department of Furniture Design, Faculty of Forestry and Wood Technology; b: Department of Economics and Economic Policy in Agribusiness, Faculty of Economics; c: Development Centre UMT, Secretariat for Lifestyle & Design Cluster, Birk Centerpark 38, 7400 Herning, Denmark; d: Satakunta University of Applied Sciences, Faculty of Technology, Satakunnankatu 23, 28130, Pori, Finland; e: Hanse-Parlament e.V., Blankeneser Landstrasse 7, 22587 Hamburg, Germany;
* Corresponding author: beata.fabisiak@up.poznan.pl
INTRODUCTION
Currently, much attention is paid to ensure the best possible comfort and quality of life for seniors. Design, ergonomics, safety, and functionality features of furniture used by seniors play an important part in this area of interest. This stems from the fact that the societies, especially in developed countries, are ageing at a rapid pace. In January 2019 people aged 65+ accounted for 20.3% of the EU-27 population, with the share of people aged 80 years or more reaching 5.8% (EC 2020a). It is interesting that the share of seniors in the EU-27 population in 2019 was 0.3 percentage points higher than a year before and 2.9 percentage points higher than the corresponding share from a decade earlier (EC 2020b). Another indicator that shows the rapid pace at which the EU population is aging is the median age. The median age is the age that divides the population in two parts of equal size, that is, there are as many persons with ages above the median as there are with ages below the median (WHO 2021). The median age in the EU-27 increased 2.7 years between 2009 and 2019, rising from 41.0 years to 43.7 years (EC 2020c). When a longer period is analysed, the difference is even more evident. In 2001 the median age was 38.4 years, creating the difference of 5.3 years in comparison to the value from 2019 (EC 2020a). European Commission forecasts indicate that the number of seniors in the EU will continue to increase and will reach 149.2 million in 2050, constituting 28.5% of the EU population (EC 2019). This trend is also observed outside Europe – it is estimated that by 2050 2 billion people in the world will be over 60 years old. Additionally, countries of the Baltic Sea region (focus of this study) are affected by those demographic changes. The Baltic Sea region is a macro region of Europe constituting of countries having shorelines along the Baltic Sea: Denmark, Estonia, Latvia, Finland, Germany, Lithuania, Poland, Russia, and Sweden. The share of seniors in the populations of the selected Baltic Sea region countries is shown in Table 1.
Table 1. The Share of Seniors in the Populations of Selected Baltic Sea Region Countries
Most countries have never before dealt with such a large change in the age structure of the population. Thus, it is crucial to be prepared for the observed changes and develop product offers that meet the needs of the seniors, resulting from different types of ageing-related health and mobility issues.
Development of ageing-friendly products is an economic matter for the municipalities and governments. It is also an ethical choice for the societies taking care of seniors. Additionally, for the private sector, such as ageing-friendly designers and product developers, it is a growing business opportunity. However, most importantly, ageing-friendly products can support the autonomy of the seniors. There is an important trend to support seniors to live independently at home as long as possible, instead of placing them in institutions and care homes. This further underlines the need for finding new ways of supporting the seniors in daily living and in maintaining their functional capabilities. Properly designed furniture may offer part of this support, whereas poor designing may even cause safety hazards. Therefore, particularly important is the set of features enhancing the functionality of furniture understood as the adjustment of the product to mental and physical characteristics of the user.
Furniture for sitting constitutes an important part of everyday lives playing a significant role both in private and public spaces. One must not forget that furniture pieces for sitting are among the pieces of furniture that are used directly – the user’s body has direct contact with the furniture. Therefore, they are of crucial importance to assure comfort, safety, and quality of living.
In systematic review conducted from research in seven different countries, Harvey et al. (2013) found the majority of older adults are sedentary. Almost 60% of older adults reported sitting for more than 4 h per day, 65% sit in front of a screen for more than 3 h daily and over 55% report watching more than 2 h of TV. However, when measured objectively in a small survey, it was found that 67% of the older population were sedentary for more than 8.5 h daily. A Brazilian study by Meneguci et al. (2015) found the median value for sitting time to be 240 min a day. Participants were predominantly between 60 and 69 years old, educated, and physically active. Another study by Harvey et al. (2015) suggests much longer sitting times. According to the study, older adults are one of the most sedentary age groups, spending more than 60% (8.5 to 9.6 h) of their waking day sitting (Harvey et al. 2015). Study by Leask et al. (2015) suggested that older adults often sit most in the afternoon and evening (compared with the morning), and when they are alone at home.
To conclude, previous studies found seniors spending a relatively large amount of time sitting. Because generally considerable time spent sitting negatively affects health, it is important to support seniors to do other kinds of activities. Another important aim is to design chairs that would make sitting less unhealthy and supporting daily living, as the avoidance of sitting is not always realistic. This was the primary motivation for this study, which focuses on research of the older adults’ preferences related to chairs and other furniture used for sitting. In order to understand older adults’ needs and preferences, it is important to study which activities are performed sitting.
Palmer et al. (2019) studied sitting activities of seniors in Scotland. Most sitting activities belonged to the leisure-time domain, with many taking place at home. Watching TV was reported by all but one person, although time spent doing this varied a lot. Other home-based sitting activities included reading, doing puzzles, crosswords, or playing games, using computers or tablets, relaxing, playing an instrument, making phone calls, listening to music/radio/books, sitting in the garden, knitting, napping, thinking, sorting medication, smoking, doing paperwork, eating, and drinking, to name some. Outside the home, sitting activities included driving/traveling, sitting in parks, theaters, cafés, pubs and restaurants, learning (poetry and computer classes), as well as playing bingo, cards, and board games. These findings offer viewpoints to interpret the results of this study. However, there may be cultural differences between countries. In this study, the cultural aspect is also taken into account by comparing the answers of older adults in different countries.
The importance of well-designed chairs is emphasised by Tinietti et al. (1994), Gill et al. (1999), and Colombo et al. (1998). Different chairs designed in the right way and used in bedrooms can be used to facilitate transfer to the bed. They may also be a good support while getting dressed. The issue of the design of chairs adapted to the needs of the seniors was raised also by Šimek (2013). In his work he drew attention to the necessity of placing the seat of the chair at a greater height, implementing armrests, ensuring greater stability as well as removable, stain-resistant upholstery, mobility, and the possibility to install additional elements, such as a cup holder or a small table. Nevertheless, it would be also important to highlight that not only placing the seat of the chair at a greater height but rather offering adjustable solutions would be crucial here. A piece of furniture that is comfortable should be adjusted to various anthropometrical dimensions including people from the 5th percentile (meaning those 5% of the people who have smaller anthropometric dimensions than average dimensions of a given population). A number of publications highlight the necessity to consider universal design rules to create the furniture that is accessible to all regardless the age or mobility limitations (Østergaard 1994; Timlin and Rysenbry 2010). Though in the subject literature there is still a lack of wider studies conducted within the international scope. Thus, the purpose of this paper is to present the design requirements for age-friendly sitting furniture taking into consideration functional values of the product that are related to safety and comfort of use from the point of view of the international sample group. This is in line with the ultimate goal of supporting older adults’ daily living and health through senior-friendly furniture. As the furniture for sitting differs significantly depending on the purpose of use, in the presented study we focused on chairs for dining rooms and armchairs. Those pieces of furniture can be used both in the private households and public assisted living facilities.
METHODOLOGY
Study Design and Setting
To gather data concerning the most crucial features of senior-friendly furniture for sitting, survey research was conducted among people aged 60+. The survey form was developed by experts representing various fields: wood technology, design, geriatrics, robotics, etc., from 9 Baltic Sea region countries. The survey form consisted of open-ended and closed questions regarding preferences and problems seniors face while using furniture located in bedrooms and living rooms. The results presented below refer to the questions concerning the evaluation of various design and functionality features of furniture for sitting, including dimensions, construction, functions, material selection, and the external form. The survey form was developed in the English language and next translated by professional translate offices into national languages to facilitate the process of gathering the data in the selected countries. The research constituted the part of the international study being developed within BaltSe@nioR and BaltSe@nioR 2.0 projects to provide knowledge supporting the development of new senior-friendly products dedicated both to private and public spaces.
Participants and Survey Procedures
The study was performed through surveys (both paper and electronic ones) and direct interviews. The researched population constituted of seniors living in 6 Baltic Sea region countries: Poland, Germany, Finland, Denmark, Lithuania, and Latvia. In each of the countries, non-probability samples were obtained through unrestricted self-selected survey (Fricker 2008). Project partners distributed the questionnaires using their own professional networks and personal contacts via e-mails, newsletters, websites, and social media (Facebook, LinkedIn, etc.). Additionally, various senior organizations have been contacted to facilitate reaching the target audience. Participants were asked to fill in the questionnaires if they were 60+ years old and forward it further to whom it might concern. Therefore, the authors managed to start the process of a snowball effect (Ugolini et al. 2020). Such distribution of surveys did not allow for personal identification of individual respondents. In those countries where an electronic version of the survey was used, the research was performed via professional online survey platforms – in Denmark (Survey Monkey and AskPeople), in Germany (Survey Monkey), and in Poland (Ankietka.pl). The percentage of responses achieved via electronic survey reached 100% in Germany, 80% in Denmark and 40% in Poland. The method used in that case was a Computer-Assisted Web Interview (CAWI). The research that was done with the use of paper forms and direct interviews was done in Poland, Denmark, Finland, Latvia, and Lithuania. The percentage of respondents reached via paper surveys and direct interviews was 100% for Finland, Latvia, and Lithuania, 60% for Poland, and 20% for Denmark. All surveys were anonymous. The aim was to reach a minimum of 100 respondents in each of the participating countries.
Taking into account the percentage of completed surveys, a statistical analysis was conducted on the data obtained from 627 seniors. Women constituted 62% of the sample population, while men constituted 38% (Table 2). For the EU population the numbers were similar, in 2019 there was 57% of women and 43% of men living in the European Union. The researched population constituted of seniors living both in the urban and rural areas.
Table 2. Demographic Profile of the Respondents
Analysis Procedures
The questions analyzed in this paper were closed-ended questions, mostly of single choice. The questions concerned the following:
- “Which armchair do you prefer more: with low backrest reaching to the loins, with backrest reaching to the shoulders, with high backrest reaching above the head?”;
- “Do you have an armchair with reclining/relax function?”;
- “Would you like to have an armchair with reclining/relax function?”;
- “Should your armchair be fully upholstered, with wooden elements or with metal elements?”;
- “Which chair do you prefer more: fully wooden chair, a chair with upholstered backrest and seat, a chair with only seat upholstered?”;
- “From which chair it is easier for you to get up from: one with armrests or without armrests?”;
- “Would you like to have influence on the dimensions of the furniture prior the purchase? If yes, would you like to have influence on the height of the seat, on the width of the seat, on the depth of the seat?”;
- “Could you rate on the scale from 1-5 the functional features of furniture for sitting that are the most important for you?”;
- “Do you have a separate room dedicated for sleeping?”.
The gathered data were coded, implemented to the unified database, and subjected to statistical analysis. The coding was done by transferring each item of the questionnaire into a variable reflecting the answer of the respondent. Using the statistical grouping method, the characteristics of the needs and attitudes of seniors related to the analyzed subject were identified. In order to establish the relationship between the investigated variables and answers to the questions related to age-friendly furniture for sitting, analyzes were performed with the χ2 test of independence or with Fisher’s exact test. The Z proportion test for columns was used as a post hoc test. The level of significance was α = 0.05. When analyzing the most preferred characteristic of furniture for sitting, the respondents were asked to evaluate each feature on a scale from 1 to 5. To provide more visibility of the data achieved, the authors consolidated the results for the most important (evaluation 4 and 5) and least important (evaluation 1 and 2) furniture features. The statistical analysis was conducted using STATISTICA 13 PL software (Dell, Round Rock, TX, USA). Three main variables were taken into consideration – the age of respondents, the gender and their country of living.
The research questions concerned the recognition of the preferences of seniors regarding the design and construction features of chairs for dining rooms and armchairs. They were also to identify the similarities and differences concerning senior-friendly design and functionality features of furniture for sitting with regard to the age group, the gender and country of living. The results can constitute an inspirational source of knowledge for designers and furniture manufacturers to support them in the creation of age-friendly products and through this facilitate senior daily living.
RESULTS
The first issue investigated was the construction feature related to the height of the backrest. As much as 79% of respondents preferred high backrest reaching above the head of the user. Respondents in all studied countries presented a similar opinion (Fig. 1). In order to evaluate the relationship between the choice of the backrest and the country of living of the respondents, an analysis was performed with the Fisher exact test. The analysis showed no significant relationship between the variables, p = 0.083; V = 0.14. Such a result means that the proportions of responses in the compared groups regarding the frequency of choosing a particular type of the backrest were similar. In each of the analyzed groups, the vast majority preferred chairs with a high backrest reaching above the head. The analysis made with the statistical grouping method with regard to the age of respondents indicated that it was an important construction issue for senior respondents of all ages (Fig. 2). Particularly it was an issue for respondents above 85 years old. In this age group over 90% of respondents like to have an armchair with the backrest reaching above the head. When the gender factor was taken into consideration it turned out that slightly bigger percentage of men (85%) preferred to have an armchair with a backrest reaching above the head. For women participants a higher backrest was important for 76%, still constituting the majority of the investigated sample.
Fig. 1. Seniors’ preferences concerning the height of the backrest with regard to respondents’ country of living (source: Authors’ elaboration based on the performed survey research)
Fig. 2. Seniors’ preferences concerning the height of the backrest with regard to respondents’ age (source: Authors’ elaboration based on the performed survey research)
To recognize senior users’ needs and provide guidance for designing age-friendly armchairs, the authors decided to investigate the attitude of respondents towards increased functionality of the armchair in the form of a reclining/relax function. The number of respondents already having an armchair with the reclining function accounted for 23%. Among the users who already have such an armchair, 92% indicated they would love to still have an armchair with the reclining/relax function.
Some interesting remarks can be drawn from the data presented in Fig. 3. It shows the results on the desire to have an armchair with reclining/relax function with regard to respondents’ country of living. The majority of respondents in Latvia, Poland (over 60%), and Lithuania (over 80%) would like to have an armchair with a relax function. However, in Germany, Denmark, and Finland the respondent response was different. Analysis with the Pearson χ2 test showed a significant relationship between the country of living of the respondents and the desire to have an armchair with reclining/relax function, χ2 (5) = 31.85; p <0.001; V = 0.26. In order to establish the nature of the relationship between the variables, an additional post hoc analysis was performed using the Z proportion test (with correction of the Bonferroni significance level). The analysis showed that the inhabitants of Lithuania, significantly more often than the inhabitants of Germany and Denmark, would like to have an armchair with a reclining/relax function (p<0.05). In turn, the inhabitants of Denmark significantly less often than the inhabitants of Poland and Lithuania wanted to have such an armchair (p<0.05). Between the other groups, the differences in the frequency of the desire to have a chair with the relaxation function were statistically insignificant.
Fig. 3. Seniors’ preferences concerning the willingness to have an armchair with reclining/relax function with regard to respondents’ country of living (source: Authors’ elaboration based on the performed survey research)
Nevertheless, as far as age is the factor taken into account in the grouping method, clear evidence for the implementation of the reclining/relax function into armchairs is seen. In order to establish the relationship between the age of the respondents and the desire to have a chair with the reclining/relax function, the analysis was performed using the Pearson χ2 test. The analysis showed no significant relationships between the variables, χ2 (4) = 5.65; p = 0.227; V = 0.11. The results presented in Fig. 4 indicate that in all age groups over 60% of seniors would like to have an armchair that would allow them to adopt a comfortable, reclining posture while sitting in the armchair. The gender factor was not recognized as significant in this case. Both for men and women the majority of respondents: 67% and 63% respectively would like to have at their place of living an armchair with the reclining/relax function.
Fig. 4. Seniors’ preferences concerning the wish to have an armchair with reclining/relax function with regard to respondents’ age (source: Authors’ elaboration based on the performed survey research)
When considering design features related to the external form of the furniture, the authors wanted to investigate the preferences concerning the visibility of materials used. It turned out that over 50% of respondents would like to have an armchair that is fully upholstered. The second most preferred material was wood, used for elements such as for example supports of the armrests. This option was chosen by 29% of respondents. The least popular possibility was manufacturing the additional element from metal. Only 18% of respondents admitted they would like to have an armchair with metal elements.
The above-described issue has been investigated in more detail taking into consideration the age of respondents. In order to establish the relationship between the age of the respondents and the choice of the material visible on the armchair, an analysis was performed using the Pearson χ2 test. The analysis did not show any significant relationships for the selection of the fully upholstered armchair, χ2 (4) = 1.53; p = 0.821; V = 0.10; armchair with wooden elements, χ2 (4) = 8.97; p = 0.062; V = 0.24 and armchair with metal elements, χ2 (4) = 3.29; p = 0.511; V = 0.15. This indicates that the proportions of responses were similar in each of the analyzed groups. The obtained results show that in all age groups the majority of seniors want to have an armchair that is fully upholstered (Fig. 5).
Fig. 5. Seniors’ preferences concerning the types of materials to be visible in their armchair with regard to respondents’ age (source: Authors’ elaboration based on the performed survey research)
Apart from armchairs, chairs constitute an important furniture group when designing private and public spaces for seniors too. Thus, the authors also decided to gather data about their preferred design, construction, and functionality. The authors started by the recognition of preferred construction features. As many as 62% of respondents would like to have a chair that has both an upholstered seat and a backrest. Merely 27% would prefer the chair with only the seat upholstered, and the lowest number of respondents (11%) would choose the chair that is fully wooden.
Another important design and construction issue is equipping the chair with armrests. The data obtained revealed that 76% of people aged 60+ admit that it is easier for them to stand up and sit down when the chair is equipped with armrests. The more comprehensive analysis of the data from six countries showed that over 90% of seniors living in Denmark and Lithuania confirmed that armrests facilitate the process of using the chair (Fig. 6). Also when the gender factor was analyzed no significant impact of the gender on this preference was recognized. For both, men and women being respondents of the survey, it was easier to get up from the chair having the armrests. As many as 81% of men and 73% of surveyed women preferred this type of construction as the one facilitating the process of getting up and sitting down.
Fig. 6. Seniors’ preferences concerning the construction features of the chair with regard to respondents’ country of living (source: Authors’ elaboration based on the performed survey research)
Additionally, the results of the statistical analysis taking into consideration the age of respondents point out that this is a valuable functionality feature for seniors of all ages (Fig. 7). However, unexpectedly it turned out there was no relationship between the age and the opinion that armrests support the process of standing up and sitting down. This means that in the oldest age groups the number of users admitting it is easier to get up when a chair has armrests was not higher than in the younger age groups. Analysis with Pearson’s χ2 test did not show a significant relationship between the age of the respondents and the choice of a chair with or without armrests, χ2 (4) = 3.12; p = 0.538; V = 0.08. This means that the proportions of choosing a chair with or without armrests were similar in the analyzed age groups.
As many as 60% of respondents would like to have influence on the height of the seat before buying the furniture for sitting. Furthermore, a considerable group of respondents (56%) admitted they would like to have influence on the depth of the seat. It is important to note that over half of the respondents (51%) admitted they would like to have influence also on the width of the seat. Such high percentage values indicate that ensuring mass customization of functional dimensions of furniture when providing products for the senior population is an appreciated feature.
Fig. 7. Seniors’ preferences concerning the construction features of the chair with regard to respondents’ age (source: Authors’ elaboration based on the performed survey research)