Technology and architectural solutions are needed as a means of support in future nursing homes. This study investigated how various monodisciplinary groups of stakeholders from healthcare and technology envision the nursing home of the future and which elements are necessary for its creation. Moreover, differences in needs and interests between the various stakeholders were considered. This qualitative study gathered data via 10 simultaneous sticky note brainstorm sessions with 95 professional stakeholders, which resulted in 1459 quotes in five categories that were clustered into themes and processed into word clouds. The stakeholders prioritized the needs of the resident and placed the most importance on the fact that a nursing home is primarily a place to live in the final stages of one's life. A mix of factors related to the quality of care and the quality of the built environment and technology is needed. Given the fact that there are differences in what monodisciplinary groups of stakeholders see as an ideal nursing home, multidisciplinary approaches should be pursued in practice to incorporate as many new views and stakeholder needs as possible.
Keywords: design; qualitative; older adults; geriatrics; word clouds; Post-it®
Technology and architectural solutions are needed as a means of support in nursing homes (van Hoof et al., [
Policy and practice are increasingly shifting focus to aging-in-place. Nursing homes and other institutional forms of geriatric care pass into less important facilities within the housing and care continuum (van Hoof, Kort, & van Waarde, [
The design and construction of nursing homes is a complex and dynamic process, as the very design of these buildings forces us to consider the technology-human interface directly in terms of living-space, ethics and social priorities (van Hoof & Verkerk, [
Verkerk, Hoogland, van der Stoep, and de Vries ([
This study investigates the needs and interests related to the technological and architectural solutions of professionals working in the domain of nursing home care and the design and implementation of technological and architectural solutions. This study was performed through 10 parallel sessions. The goal of the sessions was to find out how various homogeneous and monodisciplinary groups of stakeholders envision the nursing home of the future as a place to reside and work and which elements are necessary for its creation. The focus is on the aspects of design, architecture, and technology, although other elements are also included. The sessions should clarify which insights and visions groups composed of different stakeholders have in relation to excellent nursing home care and nursing home design. At the same time, we also wanted to study whether there are differences in needs and interests between the various stakeholders and, if so, what differences there are.
An interactive, qualitative design was chosen for the study. A total of 95 participants joined in 10 sessions that were held simultaneously (Table 1) on May 28, 2013. Each session lasted for 75 minutes. The participants either had a background in healthcare or in technology and architecture. The groups consisted of largely homogeneous and monodisciplinary groups of professionals because the main goal of the sessions was to explore the differences in attitudes, interests, needs, and knowledge. This approach allowed for a comparison of the results of the various disciplines. Nursing home residents were not included because the focus was on professionals.
TABLE 1 List of Sessions and the Characteristics of the Participants
Mean number Group of years of (leaders and Characteristics Mean age work experience assistants) Background of participants (years; months) (years; months) 1 SP, TR Building services n = 8 (2 females, 6 males) 42;7 3;7 2 PG, LV Healthcare n = 10 (9 females, 1 male) 43;7 10;0 3 EW, BP Assistive aids and beds n = 9 (3 females, 6 males) 42;0 4;7 4 JH, CVL, JW Construction, real estate and maintenance n = 12 (5 females, 7 males) 46;1 6;7 5 MM, MW Policy makers n = 7 (6 females, 1 male) 46;1 3;6 6 MN, TW Education and research n = 9 (7 females, 2 males) 40;7 5;5 7 CV, CH ICT and home automation n = 11 (1 female, 10 males) 45;6 6;5 8 LZV, LOW Healthcare n = 8 (2 females, 6 males) 47;1 10;2 9 AD, CDH Healthcare n = 9 (5 females, 4 males) 53;0 12;4 10 AE, NP Architecture and interior design n = 12 (7 females, 5 males) 37;1 8;7 Total: 10 leaders, 11 assistants 5 groups healthcare, 5 groups technology n = 95 (47 females, 48 males) 44;4 7;2
First, the goal of the work sessions was explained to the participants in a plenary session. Thereafter, the groups split up. All participants signed informed consent for the use of written data and photographic material. At the same time, personal data were taken, including name, sex, date of birth, type of work and organization, and years of work experience (Table 1).
Every session was guided by a session leader and an assistant. All session leaders and assistants had been briefed about the uniform procedure and were provided with a manual and an instruction guide 1 week before the start of the sessions. The role for the session leader was to stimulate creativity and to obtain a maximum of variety in responses and input. The assistant's role was to support the session leader and to observe the group dynamics. At the same time, the assistant helped by collecting written materials and making photos. The session leaders were lecturers/researchers working with the organizing university who work in the field of healthcare and technology. The assistants were students of the Department of Industrial Design of a collaborating university of technology, one staff member with a background in Industrial Design, and one student from the Bachelor course of Applied Gerontology. These assistants were trained and skilled in the procedure and methodology applied.
At the start of each session, a scenario was read out aloud. This scenario was the same for each group:
The care for older adults residing in nursing homes is under increasing pressure due to political reforms. These reforms are related to the financial models in long-term care, aging of society, the upward change in conditions for eligibility for residence in institutions ('sheltered residence with intensive dementia care' as a lower threshold), the propagation of aging-in-place, and expected shortages of highly skilled care professionals on the labor market. In addition, there is an adverse attitude towards nursing homes in society.
This situation urges practice to look for creative solutions to be able to offer good quality and affordable care to older persons. Evidence-based practice, technology and the built environment, and satisfaction in living, comfort, and the provision of services play a role in the nursing home of the future.
In this project we look for future solutions that contribute to a positive, though realistic image of living/residing, and working in a nursing home. Three elements are of importance:
- Residents need to experience a maximum of well-being and a sense of home;
- Care professionals work with satisfaction and experience support from the built environment in the execution of their work tasks; and
- Consideration if given to sustainability and maintenance in relation to living and well-being.
In short, what does the ideal situation look like, and what is needed to realize this situation? Five elements play a role: knowing, doing, thinking, dreaming, and don't-ever-do-again:
- What do we know about the nursing home of the future? (evidence-based design, emerging trends in policy and practice)
- What do we do at this moment to make the nursing home of the future a reality? (current practice)
- What do we think of whenever we give consideration of the nursing home of the future? (financially viable hypotheses)
- What do we dream of? (hypotheses and wishes for which financial means are limited)
- What don't we ever want to do or come across in a nursing home?
Participants were invited to write down their thoughts on sticky notes (also known as Post-it® notes). These notes were supplied in five colors: knowing (dark yellow), doing (green), thinking (orange), dreaming (pink), and don't-ever-do-again (light yellow). The color scheme was printed on paper and attached to the walls as a prompt. Participants were encouraged to write down keywords or short statements on these notes and then stick them to the walls (Clark, [
Graph: FIGURE 1 View of one of the sticky notes sessions.
Participants were requested to focus on the design and construction, interior design, technology, furniture and assistive aids; on a sense of home; and on the support of work processes. After 30 minutes of brainstorming, the group as a whole was invited to cluster the sticky notes into themes (Figure 2). It was discussed with the participants whether the elements fit. Here, the adhesive property of the sticky notes was used to cluster the notes on the walls and to freely move them from one theme to another. After a plenary discussion in the group, which led to consensus, it was up to the participants to decide on the labels that were given to the themes.
Graph: FIGURE 2 Process of clustering the sticky notes.
After the sessions, the clustered notes were put into separate envelopes (one envelope contained one theme) for analysis. The assistants used a template in Microsoft Excel and Google Spreadsheet for digitalizing the notes. The first template contained five columns for each color code. The second template was used for word clusters, again each word was labeled with their own color code. These separate notes were inserted into a master template and sorted by theme and by group. Translations of the labels were made from Dutch to English. To find out how often certain themes and subjects emerged in the notes, word clouds were made (Godwin-Jones, [
Lohmann, Ziegler, and Tetzlaff ([
- Tag size: large tags attract more user attention than small tags (effect influenced by further properties, for instance, number of characters, position, neighboring tags).
- Scanning: Users scan rather than read tag clouds.
- Centering: Tags in the middle of the cloud attract more user attention than tags near the borders.
- Position: The upper left quadrant receives more user attention than the others.
- Exploration: Tag clouds provide suboptimal support when searching for specific tags.
Word clouds were made as a means to visualize the word frequency of the ideas identified during the interactive sessions. The word size represented the number of items to which a tag was applied as a presentation of each tag's popularity or importance. The results of the homogeneous groups were processed into tag clouds containing the colors of the notes. These word clouds were made using a java-applet named Wordle (
Fifteen word clouds were produced reflecting the results of the sessions. A total of 1,459 quotes were written on notes, containing 5,106 words after translation into English and 7,057 in Dutch: 267 for knowing, 321 for doing, 240 for thinking, 339 for dreaming, and 292 for don'ts. This was, on average, 15.7 notes per participant. There were 1,753 unique words after translation into English. For making the word clouds, words such as "nursing home" and "physical environment" were written as single words (without a space). Tables A and B (available as supplemental files online) show the word clouds and a selection of building-related solutions for both groups of stakeholders. Based on the sticky notes, clusters were made leading to the emergence of themes.
The sticky notes in the category knowing showed that the stakeholders from healthcare placed the most importance on the resident of the nursing home and the stakeholders from technology emphasized the resident and technology. Living was an important theme for both groups, as a nursing home is foremost a place to live and not a place where care is provided. In general, the stakeholders from healthcare underscored the importance of future trends in healthcare and the quality of life for nursing home residents. They mentioned emerging technologies as an important development that will impact the daily lives of residents and the work processes of care staff:
Many older people are not afraid of modern (assistive) technologies. Many of them are used to working with technology and ICT. (Group 6)
The stakeholders from the technology groups were well aware of the technological options and solutions for nursing home care that were available on the marketplace, and they emphasized the need for involving residents and care professionals in decision-making processes regarding the design of nursing homes and the purchase and implementation of technologies. They also showed an awareness that their own work processes need improvement to match with the expectations of their end-users.
Technology can support a longer lifespan and can reduce costs. (Group 1)
The sticky notes in the category doing showed that the stakeholders from healthcare placed the most importance on the residents and living in their answers, and so did the stakeholders from technology. Thus, living is important for both groups: a nursing home is not just an environment in which healthcare is supplied to older people. Foremost, it should be a place to live:
We need to act like the resident is still living at his/her own home. (Group 2)
Both groups showed a great awareness of technological options available for nursing home care, such as home automation technologies. At the same time, participants placed critical remarks to the current implementation of these technologies. Within Group 9, these contradictory statements were manifested:
We need more home automation technologies in nursing homes.
We need fewer home automation technologies and continue the way things were.
The coming together of various stakeholders working in the field of nursing home care was considered to be an important future development. Moreover, technology, despite all challenges, was considered to be a welcome attribute, as were environmental modifications.
More domesticity in terms of atmosphere. Assistive technologies should be kept out of sight as much as possible. (Group 3)
The sticky notes in the category thinking showed that the stakeholders from healthcare placed the most importance on the resident and care in their answers and the stakeholders from technology emphasized the resident, care, and living. Living was important for both. The number of quotes was smaller than in the previous categories. Nevertheless, there were some remarkable notions. First, the professionals from healthcare again came up with a large array of technological and architectural solutions that they thought were beneficial for the provision of healthcare and the quality of life of residents. They called for smaller spaces and small-scale solutions, as well as freedom of movement and the need to stimulate a resident's independence skills:
Staff should be coached in techniques to provide peace and structure. (Group 8)
The professionals from technology also mentioned the need for small-scale solutions and familiarity. They seemed to be aware that their skills and knowledge related to healthcare should be improved to meet the needs of their clients. Moreover, they also acknowledged that the solutions offered by them are subject to rapid developments, which make technologies rapidly become out of date:
Communal rooms should be built in smaller units. (Group 10)
The sticky notes in the category dreaming showed that the stakeholders from healthcare again emphasized the resident of the nursing home in their answers, whereas the stakeholders from technology emphasized the resident and the physical environment, care, and technology. Here, the contrasts were the largest. Care professionals envisioned a bright future for nursing home residents, including the use of light and lighting:
Dynamic lighting. (Group 2)
In their view, a future nursing home could also refer to their own home instead of a separate healthcare facility. Self-directedness and self-management were important features, as were attractive interior designs and a good quality of life. Residents should no longer share facilities, such as two-person bedrooms and shared sanitation:
A room which one can alter based on one's personal needs and wishes. (Group 5)
Even stakeholders from technology stressed the need for nursing homes to become a part of the society: facilities should no longer be built in the middle of a remote forest. In their view, technology played a large role in the nursing home of the future. Pets and other animals, both life and robotic, should be part of daily living patterns:
A fully integrated unit within a neighborhood. (Group 3)
The sticky notes in the category don'ts showed that both groups of stakeholders again placed the most importance on the residents. Stench and unwanted odors, large-scale facilities, remotely located nursing homes, and clinical and industrial looking facilities were considered to be absolute don'ts by both groups:
Clinical, hospital-like environment (color of furniture and light). (Group 6)
The management of a nursing home, both in relation to inadequate steering of the provision of care, and the implementation of technologies, were mentioned. A lack of positive stimulation and the limitations to freedom of movement were mentioned as items that need to be changed. Again, a nursing home should feel like a true home instead of like a hospital:
Letting residents wait in their room without interaction. (Group 7)
Entertaining residents as if they were children. (Group 7)
The word clouds reflected the main points of focus for the participants and exhibited that a mix of factors related to the quality of care and the quality of the built environment and technology is needed. It is clear that the participants from healthcare and technology had different views about what is important when programming the nursing home of the future. Some of the views expressed during the sessions were conflicting, even within groups, although there seemed to be a general consensus on what is truly important. Conflicting items were related to the need for technology (home automation, in particular) as a support for residents and staff. Both groups used different terminologies to describe the same ideas. Figure 3 shows the collective word cloud of all participants. There was a consensus that the resident is the most important factor in the programming and design of the nursing home of the future.
Graph: FIGURE 3 Collective word clouds of all participants.
In general, non-building–related items were more frequently mentioned than building-related items. The similarities between groups were related to self-directedness and self-management in healthcare, which was an important feature. This was related to the mutual wish for greater autonomy of nursing home residents. The resident was considered the top priority among both groups. The resident should be the central focus in every nursing home, both in terms of interpersonal treatment and in the way we build facilities. In addition, relatives and the neighborhood should be more involved in the daily lives and activities of nursing home residents. Nursing home residents should be active participants in society. Facilities that are built in the middle of a forested area were unwanted because they prevent the active engagement of nursing home residents in society. Moreover, nursing home staff should focus more on the residents' possibilities and capabilities rather than on limitations. Patronizing was considered an unwanted phenomenon, both on the level of human interaction as on the level of human-technology and human-building interaction.
When considering the similarities in the domain of housing-related solutions, the need for transparency was paramount. Participants wanted transparent buildings, with glass facades for daylight access and contact with nature. This connectedness with the outdoors was an often-mentioned phenomenon (gardens, animals, pets) to broaden the world of the nursing home residents. Moreover, there was a need for flexibility in construction, which allows maintenance staff to easily adapt the private rooms to match with the needs of the residents and care givers. Thresholds in bathrooms were considered as the most unwanted item in the built environment, as they are a limitation to independence and mobility. Home automation systems, including emergency response systems, were mentioned by both groups as helpful tools to improve safety and security and to assist care staff. This type of technology should be integrated within the home environment and should be unobtrusive. Moreover, controls should be kept as simple as possible for both residents and staff. Safety and security were considered to be important in both groups, but this should not go together with limitations to personal freedom, including medical restraints and locking up. Monotony and uniform environments were considered to be unwanted by both groups because they do not contribute to a home-like atmosphere.
There were some contradictory statements within and between groups. The most prominent was the need for a single, private room. Single rooms improve privacy and offer the possibility for customization of the interior design and choice of furniture. At the same time, single private rooms may reinforce the feelings of loneliness, given the fact that many residents have enjoyed a family life before. Furthermore, the participants with a background in healthcare emphasized the need for more assistive technologies for staff and the support of residents. At the same time, they called for a decrease in the number of assistive technologies. When looking at the true meaning of these statements, the participants in favor of a decrease actually meant making technologies less obtrusive. This, in turn, was supported by the participants from technology and design, who called for making technologies less visible and obtrusive. The call for special design features for individuals with dementia was, on one hand, emphasizing the need for familiarity through the use of older furniture and bringing in personal belongings; on the other hand, participants called for the creation of virtual environments by projecting images using beamers and screens. Here, fostering nostalgia and the introduction of modern technologies seemed to go hand-in-hand.
Participants were asked to cluster their sticky notes into themes (Table 2). Many similar themes emerged in both groups. The most important themes were interior design and construction, technology, financial aspects, emotions and feeling of home, safety and security, well-being, hygiene, communication, relatives and social contact, vision, staff and management, the client, and values. These themes can be used for programming the nursing home of the future. All main themes, apart from values, are acknowledged by the two groups of stakeholders. Some of the themes are related, such as well-being and having social contacts, as well as the feelings of home and architectural aspects.
TABLE 2 Emerging Themes per Groupa
Themes (group) Main themes Healthcare Technology Interior design and construction Building (2) Sterile environment (7) Facilities/construction/architectural aspects (4,7) Group living (2) Single-person room (4) Group dynamics (6) Scale (4,7) User-Centered Design (4) Light(ing) (4) Location (4) Green (4) Technology Home automation (4) Development of solutions (7) Financial aspects Emotions and feeling of home Atmosphere (8) Feelings/emotions (10) Experience (10) Safety and security Well-being Materials (well-being) (5) Participation (8) Motivating older people (7) Life rhythm and pastime (6) Food (3,4) Hygiene Hygiene (6) Odors/stench (4) Communication Relatives and social contacts Social relationships (7) Loneliness (4) Staff and management Work processes of staff (2) Staff (4,10) Changing role of care professionals (6) Insufficient highly skilled staff (7) New ways of working (5) Involvement/participation of staff (7) Care (5) Disrespectful treatment (7) Education (8) Time (4) Organization (4) Client: Self-directedness and autonomy Self-directedness of the client (9) Autonomy (4) Mobility (6) Locking up (7) Client (2) Independence (7) Quality (3) Dementia (4) Values Soft and hard values (1)
2
The discussion section deals with the differences and similarities in group outcomes, the inclusion of residents in research and design, evidence-based design and training, technological complexity, and a reflection on the methodologies applied. These discussion points were chosen as the participants of this study raised questions about the inclusion of residents and the need for inclusive design. Moreover, there was a latent presumption that there were large differences between the two groups of stakeholders. Technological complexity is discussed because the themes themselves are merely ingredients for the design of larger and more complex buildings. The methodologies used are not often encountered in the scientific literature and, therefore, are discussed.
What this study showed is that both groups of stakeholders put the resident first and stated that a nursing home (in whatever its form or building type it may be) is first and foremost a place to live and not a place where care is provided. This supported the notion of speaking of older individuals in nursing homes as "residents" and not as "patients." The study also showed that, for the creation of an ideal nursing home of the future, architectural and technological solutions are important elements, but activities and participation and adequate care support are just as much needed for well-being and quality of life.
Despite the limited differences between the two professional groups, there were some nuances that can be distinguished. The differences were often influenced by the personal and professional backgrounds of participants of the 10 groups. A group with representatives with a background in interior design typically emphasized the need for certain types of furniture and color schemes. Individuals with a background in healthcare often dealt with the physical environment (such as, insufficient space, thresholds in bathrooms) with their own work experience in mind. This also implied that when carrying out real design processes, it might be worthwhile to include other stakeholder groups to get a larger diversity of what is needed to create a well-functioning healthcare facility. Only in multidisciplinary groups can one account for the majority of stakeholders' needs.
None of the stakeholders mentioned guidelines, scales, and audit tools as instruments for the creation of a nursing home. Examples of such guidelines and scales are the Therapeutic Environment Screening Survey for Nursing Homes (TESS-NH) (Sloane et al., [
Although many views and ideas were shared, there were some conflicting notions between the groups, such as the need for single-person rooms. Xu, Kane, and Shamliyan ([
Many ideas written on the sticky notes could not be backed by scientific data, which is a crucial element in evidence-based design. Xu et al. ([
None of the participants could produce hard data or mentioned studies dealing with evidence-based design in healthcare, or, for example, review studies by Ulrich et al. ([
Given the obstacles stated above, the exposure of practitioners to academic literature on evidence-based design, the implementation of technology in healthcare, and psychological findings on quality of life needs to be improved. Education on how to interpret and use academic literature and statistics (and setting aside professional development time to read and discuss journal articles and other references with colleagues) seems indispensable. At the same time, it needs to be ensured that such sources are made available (i.e., subscribed to) by government agencies or other organizations. Verbeek, Zwakhalen, Schols, and Hamers ([
The results of the sticky notes session showed that the two groups of stakeholders do not differ, to a large extent, in their views on what is needed for the creation of the nursing home of the future (both technological and architectural solutions) and other aspects. This refutes the notion that the two domains of healthcare and technology are irreconcilable, or at least have different views on the provision of healthcare. Both groups of stakeholders are well aware of their own short comings and strengths and were willing to share their views with their counterparts. The monodisciplinary character of the groups may have contributed to an open attitude and willingness to share and speak freely, as people were among peers. Both groups put most focus on the resident. However, this raises a question about whose needs are being served. Do stakeholders from both domains adequately articulate the needs of residents? Neither residents nor their representatives were included in this study, and a validation study should be conducted to examine whether the emerging themes are also shared by actual residents. The need for user-centered design (also referred to as participatory design) was mentioned by stakeholders from construction, real estate, and maintenance as one of the subthemes in Table 2.
The involvement of the internal end-users in the design process of a nursing home is important. Apart from care professionals and maintenance staff, these are residents and their relatives. In the rather philosophical paper by Heylighen and Bianchin ([
Heylighen and Bianchin ([
When considering these conclusions and acknowledging the importance of constructing convergence, including professional stakeholders working in a nursing home seems to be less arduous a task as engaging in design processes with older residents themselves, particularly those with psychogeriatric health problems. Nevertheless, making small contributions by both residents and their relatives (as proxy users) should be encouraged for the sake of inclusivity. This implies getting residents involved in the creation of new nursing homes, as was suggested by Heylighen and Bianchin ([
The creation of a new healthcare facility is a complex task, most of all because of the large number of relevant stakeholders. Verkerk et al. ([
The skin (windows and daylight access) and site (gardens, no remote location) were also mentioned, just as structure (flexibility of walls), albeit less often. Space is an important feature in nursing homes, both in terms of way-finding (Marquardt, [
When designing nursing homes, it seems important to include the surroundings of a facility and think over the design of outdoor spaces as well. In relation to the domain of services, apart from the aforementioned lighting systems, many participants stressed the importance of designing for the senses, particularly in relation to the indoor environmental parameters (light, sound, temperature, indoor air quality, and odors). These parameters were mentioned by many groups of stakeholders, and not just the architects and participants from the building services sector. It is known that the perception of the indoor environment changes due to biological aging and dementia, and this, in turn, can impact the quality of life of nursing home residents (Barrett, Barrett, & Davies, [
Within the scientific literature, the use of sticky notes and making word clouds have not been reported as a methodology for investigating homes, buildings, and occupants' needs. There are other qualitative methodologies for studying these phenomena, such as interviewing, sketching, writing, and through photographs, as was applied by Eggen, Hollemans, and van de Sluis ([
Creating an ideal nursing home requires the fulfilment of a large number of factors, which are related to the quality of care and the quality of the built environment and technology. This study showed that professional stakeholders from the domains of healthcare and technology did not differ substantially in their views on programming and designing future nursing homes. It seemed that stereotypical thinking about both groups of stakeholders does not hold, for instance, that stakeholders from the domain of technology are only occupied with technology on their minds and do not fully consider the needs of residents and that stakeholders from the domain of healthcare have a limited knowledge of technology. Both groups put the needs of the residents first and stressed the fact that a nursing home is primarily a place to live in the final stages of one's life instead of regarding this facility merely as a place where care is provided. Given the fact that there were differences in what monodisciplinary groups of stakeholders see as an ideal nursing home, multidisciplinary approaches should be pursued in practice to incorporate as many new views and stakeholder needs as possible. The insights gained can be used to further investigate the evidence base of the identified items.
All participants of the sessions are kindly thanked for their willingness to volunteer and share their views. Tom Raijmakers, Lotte Oude Weernink, Nakul Paricharak, Chris Hoedemakers, Josha Woudstra, Lisa van der Voort, Thomas van de Werff, and Bram van der Putten are thanked for their support.
The Municipality of Eindhoven (Gemeente Eindhoven) and Stichting Promotie Installatietechniek (PIT) are thanked for their financial support.
Supplemental data for this article can be accessed at
By J. van Hoof; M. H. Wetzels; A. M. C. Dooremalen; M. E. Nieboer; P. J. L. M. van Gorkom; A. M. E. Eyck; E. L. M. Zwerts-Verhelst; S. T. M. Peek; C. S. van der Voort; M. J. G. A. Moonen; C. J. M. L. van Dijck-Heinen; H. T. G. Weffers; R. A. Overdiep; S. Aarts; C. Vissers-Luijcks and E. J. M. Wouters
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