Abstract
Background
As populations age, there is an increasing need to ensure that older persons stay active and healthy, and this is termed “healthy ageing.”1,2 Healthy ageing is emerging as a vital key concept, which, according to the Active Ageing Policy Framework, implies a focus on the maintenance of health throughout life, often through lifestyle choices and preventive measures.1 -3 Healthy ageing should be a useful model that tries to explore traits associated with, among others, exceptional longevity, 4 management of chronic diseases, 5 lifestyle choices, social, economic, behavioral and environmental factors that affect the health of a person. 6 The World Health Organization (WHO) defines healthy aging as the “process of development and maintenance of functional capacity that allows well-being at an advanced age.” Functional capacity is the combination of the individual’s intrinsic capacity, the relevant environmental characteristics and their interactions with the individual.7 -9 Intrinsic capacity is the articulation of physical, psychosocial and mental abilities. Environmental characteristics are the context of life, including social relations. Well-being is unique and permeated with subjective aspirations, including feelings of fulfilment, satisfaction and happiness. 10
WHO’s model of healthy ageing outlines a public health framework for action on ageing built around a reconceptualization of Healthy Ageing that focuses on an older person’s ability to do the things they have reason to value, rather than the absence of disease.7,9 In 2016, the 194 Member States of WHO used this framework as the basis for the Global strategy and action plan on ageing and health.7,9 This framework has now been superseded by the United Nations Decade of healthy ageing (2021-2030) 11 and among its action priorities is ageism; a stereotype of how we think, how we feel and how we act towards people on the basis of their age. People of all ages are affected but particularly, ageism has negative effects on the health and well-being of older people. Within this action area, WHO is working to change how we think, feel, and act towards age and ageing by generating evidence on the drivers of ageism, building a global coalition to combat it, and developing tools and resources to take action.7,9,11 Therefore, our interest is in exploring perceptions of healthy ageing, and whether those with negative connotations may be a result of ageism; it is timely and relevant to the UN decade of healthy ageing.
Ageing populations across the globe are expected to increasingly present public health challenges and thus global planning for ageing is an urgent priority that requires robust data and evidence. In most sub-Saharan Africa (SSA) countries, while the older population makes up a relatively small proportion of the population, the number of older people is projected to increase to over 67 million by 2030 from 34 million people aged 60+ in 2005. 12 The United Nations has advocated for more evidence/data on the status and the needs of older persons in SSA to bridge the gap in our understanding of the demographics, health concerns and self-perception of older people. 13 For instance, despite having worse health compared to younger age groups, older people in sub sub-Saharan Africa have been observed to use health services much less than younger people. This disparity signals possible age-based inequalities in access to health services, 14 but it is likely to also be driven by perception of needs and what it means and feel to be “older” in these contexts. Data and evidence on healthy ageing is available from high income countries (HICs) but these are not directly actionable by SSA stakeholders.15 -18 That knowledge needs to be understood and strengthened in the complex demographic, social, medical, economic and cultural contexts of low and middle income countries (LMICs).
Populations with healthy lifestyles have a significantly greater life expectancy and less morbidity due to healthy meal planning, communication technology such as e-health, psychological and clinical interventions, and provision of information, among others. These are all promising approaches to promoting healthy ageing. 19 In a Nigerian study, healthy ageing was perceived as being “strong” and able to move around, without support for mobility and performing daily activities; practicing healthy habits with behaviors of self-responsibility, being optimistic, happy and spiritual and having social support from family and friends. 20 In Cameroon, a study on determinants of active and healthy ageing revealed that good housing and more so self-owned, improved health care and support services; engagement in voluntary work, political process, and livelihood activities were all essential for older persons’ safety and well-being. 1 In Iran, participants reported that being in good physical health, having no chronic illnesses and functional independence are first signs of healthy ageing while having enough money was considered an important factor for health in old age. Social support also played an important role in maintaining the health of older people; strategies such as financial planning for the future, engaging in physical activity, a nutritious diet while young were perceived as all leading to healthy ageing. And spirituality and religious practices were seen as playing a protective role against ageing problems and challenges. 21
The above findings revealed healthy ageing perceptions and how they cut across developing and least developing nations—healthy eating, physical activities, financial security, spirituality and absence of disease. Notably, there are similarities across studies in the perceptions of older persons about what interferes with healthy ageing. It should further be noted that, perspectives reported from the reviewed studies were only from older persons and yet views from different stakeholders are needed to understand this.
This paper presents findings from one part of a multidisciplinary project looking at the complexity of ageing in Uganda from multiple lens. An established partnership of academics and practicing artists, non-governmental and governmental organizations in Uganda and the United Kingdom (UK), linked with a community of older people in Wakiso, Uganda, co-developed the project to ensure relevance to the local and national priorities. This partnership was driven by the UN Agenda for Sustainable Development goal to “Ensure healthy lives and promote well-being for all at all ages,” and the urgency to develop SSA specific knowledge to foster sustainable health and well-being. Our study specifically aimed to explore perceptions of and attitudes towards ageing using a community based participatory research (CBPR).
Methods
A CBPR approach was employed, for it is an involving collective, reflective and systematic inquiry in which researchers and community stakeholders engage as equal partners in all steps of the research process with the goals of educating, improving practice or bringing about social change. 22 It increases knowledge and understanding of a given phenomenon and integrates the knowledge gained with interventions for policy or social change benefiting the community members; contributes to sharing of expertise in the decision-making and ownership; and creates strong links as a result of meeting with stakeholders.22 -25 In this study, community stakeholders were involved in the design of the project by engaging in a workshop in preparation for the project and later in community dialogues before actual data collection. The study used WHO model of healthy ageing to ground the findings. 7
Study Design
Qualitative research methods were used to collect data and included use of focus group discussions and key informant interviews. Focus group discussion is a technique where a researcher assembles a group of individuals to discuss a specific topic, aiming to draw from the complex personal experiences, beliefs, perceptions and attitudes of the participants through a moderated interaction. 26 Key informant interviews are qualitative in-depth interviews with people who know what is going on in the community. The purpose of the interviews was to collect information from a wide range of people—including community leaders or professionals—who are experts and have first-hand knowledge about the community and can provide insight on the nature of problems and give recommendations. Use of FGDs and key informants in the study enabled triangulation of information from different participants/respondents. Triangulation facilitates validation of data through cross verification from different sources. It also increases the chance to control or assesses some of the factors influencing the study results.
Study Site
Kampala metropolitan that consists of the city Kampala and the neighboring Wakiso district among other districts; had an estimated population of 2,986,000 according to Metro-Area population statistics, 2018. 27 Wakiso, the most populous district in Uganda with nearly 2 million people has a population of over 400 older people aged 60 years and above. 27 The district was specifically chosen for this study because it allowed representation of both urban and rural older persons. The study was conducted in Busukuma sub-county located to the north-east of Wakiso district and comprising eight parishes and 78 villages. We engaged with older persons living in four villages of Nabitalo, Wamirongo, Luwunga, and Kiwenda selected from Kiwenda and Wamirongo parishes that covered both rural, peri-urban and urban settings of the sub county. NGOS dealing with older persons in and around Kampala city including leaders that represent older persons at sub-county, division, town council and ministry levels were included in the study to provide key information on older people from these communities.
Procedures
Between November 2018 and January 2019, community dialogues were held with the aim of introducing the study to the people living in the four target villages so as to establish relationships before undertaking data collection. This was the second step of CBPR after initially having engaged with communities in a workshop in preparation for the study. A topic guide was used to pilot test the focus group discussions and key informant interviews. The tools were internally, but not externally, validated and pilot tested.
The key questions in both guides were asked to the different participants and respondents and included societal understanding of ageing, role of older persons and their current and future needs. Each of those main questions had numerous specific questions; among which was one on perceptions of healthy ageing.
In each community, the study liaison officer collaborated with local leaders who assisted in identifying and mobilizing community members to participate in community dialogues and thereafter in data collection. From March to May 2019, older persons 60 years and older in the study villages were approached and purposively selected to participate in FGDs. Other participants included community local leaders who comprised chairpersons, opinion and religious leaders; other community members below 60 years of age (20-30 years, 31-50 years) and Community Based Organization (CBO) leaders.
Inclusion and exclusion criteria: All those in the target population who were willing and able to give informed consent were allowed to participate in the study. Those who did not have time to participate in the activity or were unwilling to have their interview audio recorded were excluded from the study. All older persons who participated were responding themselves without support.
From May to July 2019, key informants were identified and approached for in-depth interviews. They included policy makers drawn from the Ministry of Gender, Labor and Social Development and Ministry of Health. Interviews aimed at understanding their views about the study hence helping in setting priorities for future research. Other interviews were held with staff from NGOs working with the elderly while the remainder were representatives of female and male older persons at district and village levels (see Table 1 for details). All discussions and interviews were held in quiet places and often, participants offered their home gardens, under trees or sitting rooms as venues for discussions. Each FGD participant and KII respondent consented to take part in the study by signing a consent form and retaining one for him/herself. Consent to use a recorder was sought, and discussions and interviews were audio recorded. A moderator, who was part of the research team led the discussions and interviews while a note taker, also on the research team took notes as discussions and interviews went on. Both the moderator and note taker were Ugandan women well trained in qualitative research methods and trusted by the community and participants. The group discussions comprised 6 to 12 people and lasted between 1 h and 30 min to 2 h. Key Informant interviews lasted for about 1 h. Group discussions and interviews were held once, no repeats were conducted.
Characteristics of FGD Participants and Key Informants.
Data Analysis
Preliminary data analysis was conducted concurrently with data collection which enabled the study team to assess when content saturation of key topics was achieved. The research team took note of key issues as discussions and interviews progressed. The notes were kept for further reference during progress reports and actual analysis. After field work, recorded data was translated into English by an expert bilingual translator. In order to ensure accuracy, the translated transcripts were crosschecked by the research team who had expertise in both English and Luganda, the local language. The process of reading through the transcripts and notes helped to draw more attention to thematic categories that were important in preliminary analysis. A thematic and content analysis framework was then drawn and it captured the main themes and subthemes from the data. Under each main theme and subtheme, thematic codes and emerging themes were generated for content and deductive analysis. All were analyzed against the different six categories of people who participated and included: key informants, community based organizations (CBOs), male older persons, female older persons, other community members, and community leaders. For quality assurance, the thematic and content coding all of which was coded in a manually generated thematic and content analysis framework was double checked by another team member on the study. Key participants’ perspectives and experiences were identified and used as quotations in the presentation of findings.
Quality Control and Quality Assurance
The study sites were pre-visited to obtain relevant updated sampling frames for qualitative work. During the planning phase, members of the research team were oriented on issues pertaining to the research project. Prior to data collection, the data research team received training on qualitative data collection tools. Data collection was done in a pair of a moderator and note-taker. The social scientist lead was actively involved in some stages of data collection and supervised it as one of the quality control measures. All group discussions were segregated by sex to enable women and men discuss ageing issues that concerned them in depth as either males or females without any hesitation.
Preliminary analysis was done as an ongoing process during field work so as to explore significant as well as unclear findings. On each day, field notes were written out in detail and reflections were made to help in subsequent data collection.
Ethical Conduct of the Study
The study was conducted in accordance with legal and regulatory requirements, as well as the general principles set forth in the International Ethical Guidelines for Biomedical Research Involving Human Subjects and the Declaration of Helsinki. In addition, the study was conducted in accordance with the protocol, Good Clinical Practice (GCP) guidelines, and applicable local regulatory requirements and laws.
Results
A total of 13 FGDs and 11 key informant interviews were conducted. The target number for FGDs was met while that for key informants exceeded by three because we later observed it was necessary to interview staff from NGOs dealing with older persons.
Characteristics of Study Participants and Respondents
Participants in FGDs were older persons, other community members, community leaders and CBO leaders that were drawn from four villages in Busukuma sub-county. Key informants were NGO staff, representatives of older persons at subcounty, division/town council and ministry staff.
Perceptions of Healthy Ageing
Participants were asked what they perceived healthy ageing to be; perceptions ranged from physical, emotional/behavioral to socio-economic. Each of the three key themes generated sub themes and for every subtheme, numerous perceptions on healthy ageing were reported. Other emerging findings are also reported.
Physical perceptions
Physical fitness
To some participants, healthy ageing meant that a person had to keep active, participate in community activities and had the capacity to do what she or he desires. The ability to walk, cultivate, fetch water, prepare meals and walk long distances, rarely falls sick were all mentioned as healthy ageing indicators including good nutrition. All the different categories of participants concurred on these indicators.
Healthy ageing entails physical fitness and it’s not about doing nothing, one should get involved in activities that you can afford to do that are not straining. You live like a normal person and that keeps you active and healthy (Key Informant—Ministry). A healthy ageing person is one who can still fetch water from the well and come back home and prepare meals. (woman in FGD with other Community members (31-50 years).
Absence of health challenges
Participants further perceived healthy ageing as a condition where one is free from complications associated with ageing, s/he is able to fight disease and when sick, gets well quickly. . Someone can walk, do household chores, has clear vision, can understand drug prescriptions, walks straight, can go to a health facility on his own, can use a mobile phone and thinks straight.
A person whose body still has the ability to fight diseases just like the youth and recovers quickly when s/he falls sick ages healthy. (man in FGD with other Community members—31-50 years). The person. . .. . ..is able to go to the health facility by himself, s/he is still able to understand drug prescriptions and also can use a mobile phone (Key Informant—Busukuma sub-county).
Good physical appearance
Looking good with a healthy skin was perceived as healthy ageing. The results of a healthy nice looking skin were attributed to one taking care of himself or herself well, having a balanced diet, observes good sanitation and hygiene like bathing regularly. All enhanced good physical appearance.
A person who looks after himself well, eats a balanced diet, practices good hygiene and sanitation, has a nice looking skin, and ages healthy. (FGD with Female older persons).
Looking younger than actual age
A person who has aged healthy was perceived to look many years younger than his or her age and this would be reflected in a nice looking skin, not walking while bending, energetic and doing household chores. Participants similarly perceived this as “ageing at a slow pace.”
In my opinion a 75-year-old healthy ageing person can still physically appear like a 50-year old. That is ageing at a slow pace (older man in FGD—60 years+).
Genes of body structure/genotype
One’s body structure was perceived to influence healthy ageing. For example, the ageing process of short people as compared to tall people was considered to be slow. Their sight, teeth and hearing conditions may remain functional even at the age of 100; some older persons revealed.
Emotional/behavioral perceptions
Stress-free life
Living a stress-free life was described as being well looked after by children or other household members that spend most of the time with the elderly; getting checked by a nurse at least once a week, getting massaged and not struggling to provide for themselves. Some participants, however, noted that such older persons are few. They further explained that a stress free life can even enable a 90-year old to have a clear mind with even a good sight. Having good natural immunity, physically looking well with a functioning brain, being provided with basic needs, eating a balanced diet, always energetic and keeping oneself engaged in work and leading a life of contentment with no regrets were all stress-free perceptions of healthy ageing.
A healthy ageing person is one who is stress free, does not hustle a lot, physically looks good and the brain also still functions very well. Even if a person is 90 years old, he can remain clear headed and with good sight (older man in FGD—60 years+).
Socio-economic perceptions
Social and economic stability
The ability for one to cater for his or her socio-economic wellbeing and have access to regular meals was perceived as healthy ageing. To other participants, healthy ageing meant being financially well and able to support others financially. The ability to provide education to children and children being able to support you later; having a good home and better still, a personal one, were all considered to be healthy ageing.
In my opinion healthy ageing is where you are doing well financially, don’t depend on other people for survival and you are even able to give financial support to other people although you are old (older woman in FGD—60 years+).
Access to medical services
Healthy ageing was perceived to be good care and ability to understand the need for medical check-ups and access them, enjoying health rights as well as having the knowledge and ability to control and treat disease.
One who is well cared for, that is to say, s/he is immediately taken to hospital when he falls sick and is treated before the illness worsens. (woman in FGD with other community members—31-50 years).
Ability to plan for the future
It was further perceived that if one planned for his or her future life and specifically so, while still young, then this person will age healthy. Planning for the future was perceived as having livestock such as cows and goats and a banana plantation.
To me I see it as a successful transition of ageing whereby the person laid good strategies of preparing for old age. For example, while still in the youthful stage, this person knew this age would come where he would need this and the other and so, because he planned in advance, after reaching that age, he would not suffer like other people of his age (older man in FGD with CBO Leaders).
Engagement in social networks
The ability to socialize by joining social self-help groups where one receives financial support from friends was perceived as healthy ageing.
Other Emerging Themes
Ageing with dignity
“Ageing with dignity” emerged as another healthy ageing theme which meant ageing while still looking good. This was regarded as having people around you, accessing medical services and engaging in physical activities.
Desire to go for prayers
It was pointed out that when one is healthy, he or she is motivated to go to any destination of his or her choice and among which was going for prayers. In another context, being healthy was perceived to be the ability to do any activity by oneself such as going for prayers.
Knowledge of body changes
Being knowledgeable about the process of ageing and body transformation, that is, how the body changes from youthfulness to old age was also considered to be healthy ageing.
I think healthy ageing could also refer to being knowledgeable like in the case of women, there are some things we go through after 48 years; then some wonder what is happening but if you are aware that it’s the time to experience what you are going through, there is a way you accept the situation and then you will know how to handle issues like hot flashes. You hear some women complaining about being warm all the time and they even go and see a health worker because they don’t know that that is the time such things are supposed to occur (Key Informant interview—NGO).
Discussion
The multidisciplinary approach that was used in the study to understand heathy ageing brought to light some themes about healthy ageing and explored what it was like to age healthily in a Ugandan setting; specifically, as perceived by not only older persons, but also by other stakeholders. The theme of physical perceptions revealed the most perceptions of healthy ageing except one—absence of health challenges—which is largely a determinant of healthy ageing. Emotional and social economic perceptions come out as determinants of healthy ageing and at the same time most were perceptions of healthy ageing except a stress free life which is more of a determinant of healthy ageing (Figure 1). In the Iran study, determinants of healthy ageing were presented as strategies for healthy ageing. 21 This therefore brings to light the interrelatedness of both healthy ageing perceptions and healthy ageing determinants/strategies, which all shape older persons’ wellbeing.

Conceptual presentation of summary of key themes on healthy ageing.
Our study further reports that physical fitness conceptualized as engaging in community activities, walking, fetching water and cultivating, including assurance of meals and good feeding are all perceived to contribute to healthy ageing (Figure 1). This is reiterated by a growing body of evidence which suggests that exercise interventions enhance physical function and performance.20,21,27 While evidence on the benefits of nutrition is inconclusive, a combined exercise and nutritional intervention show evidence of benefit. 28 Emotional perceptions of healthy ageing highlighted what a stress free life entailed and again having a balanced diet was re-echoed in reducing this stress. Availability of meals again featured in socio-economic perceptions of healthy ageing. What does this tell us? That nutrition is key in determining the physical emotional and social-economic wellbeing of older persons. It should therefore be given due priority while addressing older persons’ health. The interrelatedness of healthy ageing themes, further, calls for a multipronged approach in tackling well-being for older persons. Recent evidence suggests that multi-component interdisciplinary interventions that combine exercise, nutrition, cognitive training, and comprehensive geriatric assessment appear promising. 28 Our study’s findings partially lend support to such interventions.
In South Africa, access to services like water, sanitation, electricity and housing had significant impact on older person’s wellbeing. 29 The South African findings concur with ours where good physical appearance, a subtheme of physical perceptions of healthy ageing (Figure 1); was reported to be enhanced by, among others, good sanitation and hygiene. In a UK study on adding life to our years amongst those aged 80 and over, the greatest barrier to using public transport was poor health, with 18% of people saying their health limited their use and 16% citing difficulties with mobility. 30 The findings are interesting and add reflections to our study where physical fitness (ability to walk long distances) and absence of health challenges (walking straight) were perceived to contribute to healthy ageing. Further, healthy ageing perceptions on social economic status generated a theme on accessing medical services (Figure 1), which could have also meant the presence of physical strength to reach medical services or the ability to afford medical services which too determines healthy ageing. The UK study and our study, therefore, concur on older person’s mobility as adding life to healthy ageing.
Spirituality as a unique perception that has a bearing on healthy ageing cut across countries; these findings concur with ours where spirituality stood out as an emerging theme that was enhanced by healthy ageing and vice versa.28,31,32 There is an advantage to public health that can be gained by better understanding the connection between spirituality, religiosity and health in old age. 31 In other studies, spirituality has been associated with an improvement in subjective states of well-being and a direct effect on mental quality of life. 33 All the observed similarities in perceptions of ageing healthily across countries and regions support the relevance of the research framework of the UN Decade of Healthy Ageing (2021-2030).
The paper is grounded in the United Nations Decade of Healthy Ageing (2021-2030). 11 The framework focuses on healthy ageing by providing a conceptual direction that is based on environments, in life courses (work and family) and in wellbeing. Wellbeing, as an element of the approach to healthy ageing is described as “the total universe of human life domains that make up a “good life.” 9 Therefore, well-being as an outcome of healthy ageing, becomes central to determining the success of the Decade of Healthy Ageing actions (19). 11 The UN framework therefore concurs with our study findings that highlight elements of well-being which are embedded in the physical, emotional and socio-economic perceptions of healthy ageing; as was revealed by older persons and stakeholders (Figure 1).
The Healthy Ageing research framework further suggests that determination of a good life is grounded in the person’s assessment of their ability to be and do what they most value. 11 While healthy ageing, according to some, was perceived as being self-reliant, to others, it was having people to take care of them. The conflicting perceptions here both pointed to aspects of socio-economic stability, a theme that was loaded with many subthemes of other abilities of “being” and “doing” what one valued. “I want to be able to support others,” “to have a good personal home,” “to plan for the future,” “access medical services,” “engage in social networks for support,” etc. Therefore, the three key phrases in the UN framework—ability “to be” and “to do” what one “most values” widens the scope of older persons needs and aspirations hence guiding future models for well-being. The distinctiveness of these perceptions lies in the way they were similarly reported not only by the older persons but also by a cross section of other community members including younger people.
It is hoped that findings will strengthen the relationship between social determinants and healthy ageing including contributing to the UN Decade of Healthy Ageing (2021-2030) which aims to give everyone the opportunity to add life to years, while focusing on changing how we think, feel, and act towards ageing. 11 This is expected to be through cultivating age-friendly environments; creating integrated and responsive health care systems and services; and ensuring access to long-term care for older people who need it.
Limitations and Strengths
Our findings may have been influenced by participants’ proximity to the capital city where exposure, sensitizations and access to knowledge about healthy living are high. The nearer to the city, the more available health services are. Also Ministry of Health outreaches tend to capture mainly peri-urban areas and some of which are supported by NGOs that specifically support older persons. We recommend that a comparative study on healthy ageing be conducted in a rural area far away from Kampala city where exposure to health information is limited. The study’s main strength was that a cross section of participants was interviewed; including individuals below 60 years of age, which provided rich perceptions on healthy ageing. The study methodology of community based participatory research enabled the participation of different stakeholders at different levels hence enriching the data.
Conclusions
The paper highlights the diversity of healthy ageing perceptions and their interrelatedness. It affirms that ageing healthy does not only mean being free from disease or impairment and that ageing with dignity is dependent on one’s physical, emotional and socio-economic wellbeing. It further deduces that one’s emotional well-being and socio-economic status could consequently have a bearing on one’s physical looks. Findings propose that living a stress-free life positively impacts on one’s emotional life and that good nutrition is key to older person’s wellbeing for it cut across all the three key themes of ageing healthy—physical, emotional and socio-economic. Prioritizing nutrition interventions for older persons is therefore recommended in this study.
Spirituality, knowledge of one’s body changes and ageing with dignity were neither directly emotional, nor physical or socio-economic perceptions but rather beliefs perceived to enhance healthy ageing; they too are considered important in contributing to well-being. The interrelatedness of perceptions of healthy ageing, therefore, points to the need for a multifaceted lens in addressing challenges of ageing while appreciating various perceptions across different stakeholders and regions. Though we do recommend further research into age-based disparities in health care access, we believe that our study findings contribute to the limited data on healthy ageing in Sub Saharan Africa, and adds knowledge to the physical, emotional, social-economic and other perceptions of healthy ageing that may be useful in guiding professionals working with older persons.
Supplemental Material
sj-docx-1-inq-10.1177_00469580251314957 – Supplemental material for Ageing Healthy: Perceptions of Older Persons, Community Members, and Other Stakeholders in Uganda
Supplemental material, sj-docx-1-inq-10.1177_00469580251314957 for Ageing Healthy: Perceptions of Older Persons, Community Members, and Other Stakeholders in Uganda by Eunice L. Kyomugisha, Rachel King, Rosalind Parkes-Ratanshi, Susan Nakkazi, Carol Brayne and Louise Lafortune in INQUIRY: The Journal of Health Care Organization, Provision, and Financing
Footnotes
Data Availability
Declaration of Conflicting Interests
Funding
Ethical Approval
Ethical Conduct of the Study
Supplemental Material
References
Supplementary Material
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