Lay Definitions of Successful Ageing and Contributing Factors among Croatian Older Adults: A Thematic Analysis of Qualitative Data

This work is a part of the research project Successful ageing: Development and validation of an integrated multidimensional model [ Uspješno starenje: Razvoj i validacija integriranog višedimenzionalnog modela , IP.01.2021.21], supported by the University of Zadar, Croatia.


Introduction
Due to increasing life expectancy and the growing proportion of older people in the world population, successful ageing (SA) has become one of the most important topics in gerontology, with an enormous number of studies whose results are published daily.This concept has shifted the traditional research interest from the negative aspects of ageing related to chronic diseases, deterioration, and losses in various aspects of functioning to the positive aspects, i.e., the possibility of maintaining or even improving the quality of life in later years.Similar terms can be found in the literature, such as healthy, vital, active, positive, productive, optimal ageing, etc. (Bowling, 2007;Depp & Jeste, 2006;Fernandez-Ballesteros et al., 2013) that refer to the idea of having a good old age or ageing well.However, compared to the similar concepts mentioned above, SA has a broader meaning, as it includes a biomedical, psychological, as well as a social component.Therefore, it could be said that in most studies SA actually refers to the basic idea of ageing well (Fernandez-Ballesteros et al., 2013).

Definitions and Models of Successful Ageing
Despite the numerous studies that have addressed the SA construct, consensus has not yet been reached on its meaning, its components, and its operational definition.The diversity of the ageing process, the great heterogeneity of the older population, the constant social changes in different cultural contexts, and the vague meaning of success make a universal definition of SA difficult to reach (Iwamasa & Iwasaki, 2011).
Successful ageing can be viewed in two ways -as an outcome or as a process (Von Faber et al., 2001).The first perspective views SA as a state or outcome of the ageing process at a particular point in life, as in probably the most influential model of SA -Rowe and Kahn's (1998) model.The second perspective understands SA as a continuous process of adaptation to ongoing changes and the interplay of gains and losses in the ageing process, as in Baltes and Baltes ' (1990) model of selective optimization with compensation.
In addition to these two main perspectives, two main directions in the research of SA can be identified: the biomedical and the psychosocial.The first emphasizes the maintenance of physical and cognitive health and functioning, that is, the absence or low risk of disease and disability, as in the model of Rowe and Kahn (1998).However, the biomedical approach has been criticized for focusing on disease and disability and establishing rigid criteria for SA that are difficult to achieve for the majority of older people, especially when it comes to the absence or low likelihood of chronic disease and functional limitations.Moreover, the biomedical perspective does not take into account the subjective views of older people when defining SA (Bowling & Dieppe, 2005;Strawbridge et al., 2002).On the other hand, many authors (e.g., Montross et al., 2006;Stewart et al., 2019;Strawbridge et al., 2002) believe that even people with severe chronic conditions can be considered successful agers if they themselves believe that they have aged successfully.Therefore, the older adults' subjective perception of SA, which often differs greatly from objective biomedical criteria, should also be considered (Stewart et al., 2019;Strawbridge et al., 2002).
In response to the limitations of the biomedical approach, a psychosocial approach emerged.It places great emphasis on the social component of SA, i.e., good social functioning and maintenance of good social relationships as necessary components of SA.In addition, it emphasizes the importance of positive psychological resources for SA, such as life satisfaction and other aspects of wellbeing, personal growth, self-esteem, self-efficacy, optimism, resilience, independence, control, effective coping strategies, and sense of purpose (Bowling, 2007).Only a small percentage of older people meet the biomedical or so-called objective criteria of absence of disease and functional limitations, while most older people meet the subjective and psychosocial criteria related to psychological adjustment, good social relationships, and sense of purpose.In other words, most older people rate themselves as successful agers (Jeste et al., 2010).Accordingly, another study conducted on a sample of community-dwelling Croatian older people demonstrated that only 7.9% of the participants met the criteria of Rowe and Kahn's model, while the application of the alternative model criteria (including good subjective health, perception of good financial situation, and high levels of happiness) resulted in a substantially higher percentage of successful agers (19.4%) in the same sample (Ambrosi-Randić et al., 2018).However, neither the biomedical nor, to a lesser extent, the psychosocial approach to SA have considered the perspective of older people themselves or the lay perspective on SA in general.

Laypersons' Definitions of Successful Ageing
Lay perspectives on SA can complement researchers' definitions (Montross et al., 2006;Stawbridge et al., 2002), improving their validity and social and health policy relevance (Bowling & Dieppe, 2005).The knowledge of how older people view SA can serve as a starting point for developing policies and interventions that promote SA in a particular sociocultural setting (Bowling, 2006).For these reasons, lay perceptions of SA have been increasingly studied recently.
Research on lay perceptions of SA is based on a qualitative method.A growing number of qualitative studies of SA using interviews, focus groups or open-ended questions in questionnaires reveal that older people report numerous and varied determinants and components of SA and often view the SA construct as more complex and heterogeneous than researchers in their definitions (Bowling, 2006;Cosco et al., 2013;Jopp et al., 2015;Nosraty et al., 2015;Phelan et al., 2004;Reichstadt et al., 2007;Von Faber et al., 2001, etc).These lay definitions go beyond physical health and functioning.They also include factors that researchers have overlooked or given less importance to, such as meaning in life, spirituality, financial security, living conditions, learning new things, achievement and productivity, setting life goals, physical appearance, sense of humour, etc. (Bowling, 2006;Bowling & Iliffe, 2006).A comparison of several different models of SA found the lay model to be the most complex and valid (Bowling & Iliffe, 2006).
An interesting review of 26 studies that looked at lay perceptions of SA, primarily conducted in the USA and Canada (Cosco et al., 2013) found that psychosocial components such as social engagement and personal resources (e.g., resilience, adaptation, and acceptance) were the most frequently cited components of SA.Some other studies have also shown that older people place more importance on psychosocial factors such as a positive attitude, the ability to adapt to change, and engagement than on physical health and the absence of disease in their understanding of SA (Reichstadt et al., 2007), and emphasize the importance of self-acceptance and self-contentment, as well as engagement with life and self-growth in later years (Reichstadt et al., 2010).
A recent systematic review and cross-cultural comparison of lay definitions of SA, which included studies in 13 countries across Western Europe, North America, the Middle East, Asia, and Oceania, published between 2010 and 2020, showed that older people most frequently cite social engagement and a positive attitude as components of SA (Reich et al., 2020).The components of independence and physical health were also well represented in the studies included in this review, while the least frequently identified components of SA were cognitive health and spirituality.
New-generation models of SA tend to be holistic in orientation, multidisciplinary, and multidimensional.Such models include both objective measures and subjective self-assessment of SA, i.e., components of biomedical, psychosocial, and lay models (Cosco et al., 2015;Parslow et al., 2011;Pruchno et al., 2010;Vahia et al., 2012;Young et al., 2009).They are increasingly represented and recognize the importance of incorporating lay perceptions of SA into researchers' conceptualizations.

Cultural Differences in Lay Perspectives on Successful Ageing
There is no universal stance regarding the nature and extent of cultural influence on lay definitions of SA.For example, some authors report cross-cultural differences (Iwamasa & Iwasaki, 2011;Reich et al., 2020;Torres, 2006), while others find no major differences (Jopp et al., 2015) in lay perceptions of SA in cross-cultural comparisons.Generally, there is agreement that the process of ageing is culturally determined (Rowe & Kahn, 2015), and therefore, perceptions of what constitutes SA are also influenced by the cultural context.The prevailing beliefs in a particular culture about what is important to SA (e.g., health or good social relationships) may influence the perceptions of people in that specific culture as well as their subjective experience of ageing.Bowling (2007) believes that social and cultural norms and expectations have a much greater impact on how researchers conceptualize SA compared to lay people.Therefore, she points out that while we should not neglect the role of culture when considering SA, there are probably common values that are universal across cultures.Similarly, Jopp et al. (2015) note that the meaning of SA, which is contained in lay people's conceptions, is determined more by the common ideas shared by these conceptions than by individual differences in terms of stage in the life cycle, gender, or culture.

The Aim of the Present Study
The non-Western countries, such as Southeastern European countries, are underrepresented in research on lay perceptions of SA.Consequently, we do not know much about how older people in these countries, including Croatia, perceive SA and whether their perceptions are similar to those of older people in Western Europe or North and Latin America.It could be expected that some cultural specificities in lay perspectives on SA will emerge considering different cultural background, living standard, value systems etc. in Southeastern compared to Western European countries.For example, due to their socialist heritage, people in Southeastern Europe may place more emphasis on collectivist values, such as social connectedness or harmony in social relations for SA compared to Western countries.Besides, people in Southeastern European countries may place more emphasis on financial security, due to their worse standard of living, compared to Western countries.Therefore, to improve the current knowledge regarding cultural differences and similarities in lay perceptions of SA, we conducted a qualitative study using interviews with older people living in Croatia to explore their definitions of SA and the factors they believe contribute to or enhance SA.In addition, we examined whether they rated themselves as ageing successfully.To our knowledge, this is the first study on lay perspectives of SA in Croatia and one of the few studies dealing with lay concepts of SA in non-Western European countries.The study is conducted within the research project Successful ageing: Development and validation of an integrated multidimensional model, supported by the University of Zadar, Croatia.The research described in this paper was conducted within the first qualitative stage of the project, which goal is to examine how Croatian older people perceive SA, while the main goal of the second stage of the project is development and validation of an extended multidimensional model of SA.The model will be supplemented by the components of SA that, in the first qualitative stage of the project, emerge as important for understanding SA in the Croatian cultural context, but were not included in previous researchers' SA models.

Participants
The study was conducted on a sample that included 95 community-dwelling adults aged 65 years or older (M = 75.23 years, SD = 7.03, age range: 65-90 years) with heterogeneous sociodemographic characteristics from different regions of the Republic of Croatia.Although it was a convenience sample, when recruiting the subjects, we made sure that different age subgroups of older people (65-75, 76-85, 85+ years) were represented in the sample, as well as men (49.5%) and women (50.5%).Most participants had completed high school (53%).Twenty-two per cent of participants reported having an incomplete or completed elementary education, while 25% had a college degree.The majority of participants were married (70%), while the other were mostly widowed (25%).Four people reported being divorced and only one person reported never having been married.All participants lived in their own household or in the household of their children, mostly with their spouse only (40%) or in an extended family with children and grandchildren (30%).Nine individuals (9.7%) reported living alone, 15% with a spouse and children, 3% with children only, and 2.2% with another person who was not a close family member.The majority of participants lived in cities (43%), while 30% lived in rural areas and 27% in smaller towns.

Measures and Procedure
The lead researcher (the first author) and psychology students from the University of Zadar, who had previously been trained, conducted the semi-structured individual interviews.Some of the older persons interviewed were acquaintances of the interviewers, while others were previously unknown to the interviewers and were recruited using the snowballing technique.After being informed about the purpose of the study, the procedure, and ethical issues, participants gave their informed oral consent to participate in the study and their consent to audio-record and transcribe the interview.To answer the main research problem related to lay definitions of SA and contributing factors, participants were asked two open-ended questions: 'What does successful ageing mean to you, that is, what do you think constitutes successful ageing?' and 'What do you think are the things that contribute to or enhance successful ageing?'When needed, additional questions related to these two main questions were asked (e.g. when respondents had difficulty understanding the questions or when their answers were very scarce).We also asked our participants to rate whether they themselves were ageing successfully with a simple 'yes' or 'no' answer.We used the question, 'What would you say -have you aged successfully?'Data on participants' basic sociodemographic characteristics: gender, age, place of residence, education, marital status, and with whom and where they live were also collected, after answering the main research questions.Depending on the participants' choice, interviews were conducted either face-to-face (44% of interviews) or by telephone (56% of interviews).Interviews lasted up to 40 minutes, but mostly between 4 and 7 minutes.Face-to-face interviews were conducted at the participants' homes or at another location of their preference.The study was approved by the Ethics Committee of the University of Zadar, Croatia.

Data Analysis
To understand participants' lay perceptions of SA and the factors that might facilitate it, we used thematic analysis and an inductive, data-driven approach (Braun & Clarke, 2006).Transcripts of the interviews in Croatian, which included responses to questions about the definitions of SA and things that could promote it, were subjected to thematic analysis, through six phases described by Brown and Clarke (2006).The first one is familiarizing with the data through repeated reading of the transcripts, comparing the transcripts with the original audio recordings, and searching for meanings and patterns in the data.In the second phase, initial codes or meaningful basic segments of the data were generated.Two authors, both of whom are well acquainted with the concept of SA and the related literature, conducted the coding independently and manually.Disagreements between two coders in code descriptions were resolved by reaching a consensus and refining the codes when appropriate.Then, in the next two phases overarching major themes and sub-themes were derived by study authors, considering their validity in relation to the data obtained, and subsequently, these themes and sub-themes were defined and labelled.The last phase of the thematic analysis process is producing the report about the qualitative data, with direct quotes from participants for each main theme.This report is presented in the following results and discussion sections.
Responses to the first question on the definition and components of SA and responses to the second question on contributing factors were analyzed separately to distinguish between components and determinants/contributing factors of SA.

Results
From the codes identified in responses to the first question on components and the second question on factors contributing to SA respectively, we extracted themes and subthemes related to components of SA (Appendix, Table 1) and those related to contributing factors (Appendix, Table 2).The representation of the main themes, i.e., the number of respondents who mentioned each theme is also presented in the tables.

Components of Successful Ageing
Using thematic analysis, we derived six main themes from the responses to the question about the definitions and components of SA.These are: 1) physical/physiological component, 2) cognitive and psychological component, 3) engagement and activity, 4) social component, 5) existential and financial security and stability, and 6) independence.The definition of successful ageing was on average 50 to 70 words long.All definitions included several themes, usually three to four per one definition/answer.
The physical/physiological components were mentioned most frequently (by 77% of participants) and were divided into three subthemes.The first subtheme related to general health and physical functioning and freedom from pain (e.g., "It [successful ageing] in the first place means good health and that you don't have any major health problems", "Successful ageing includes when you are free of pain").The second subtheme is related to healthy habits/lifestyle and health maintenance behaviours (e.g., "Successful ageing includes eating healthily", "It is important not to exaggerate with food, alcohol or smoking, and to stay physically active").The third subtheme included mobility and the associated ability to perform activities of daily living independently (e.g., "In my opinion successful ageing means that I can take care of myself in every way").
The cognitive and psychological component was also strongly represented in the interviews (by 48% of respondents).It was divided into four subthemes: a) good life in general b) subjective well-being, c) psychological resources, and d) good cognitive functioning.Most of the responses were related to subthemes of good life (e.g., a peaceful life, a harmonious life or a balanced life, life satisfaction, a normal life, no major worries and problems in life) and well-being (overall satisfaction, personal contentment, happiness, feeling good, being cheerful, personal satisfaction, peace of mind, no stress, etc.).Sample quotes from the participants' responses are: "Successful ageing is having a peaceful life", "…when you don't have major worries and problems", "…to be content", "…when you feel good".Psychological resources were also well represented in the respondents' answers.This category was very heterogeneous and included various resources, but mainly a positive attitude and outlook, optimism, acceptance of reality and changes in the ageing process, good adaptation and coping with life's challenges, and self-acceptance (e.g., "…the second important thing is positive thinking, positive attitude", "that you cope well with all the things life brings to you").The subtheme of good cognitive functioning was mentioned least frequently within the cognitive and psychological component (e.g., maintaining good memory and cognition in general).Following are examples that reflect this subtheme: "Successful ageing means… to preserve good memory" or "…. that the brain is still working well".
Responses related to the engagement and activity component were also mentioned rather frequently (by 42% of participants).They were categorized into five subthemes: a) being active and engaged in general, b) continuing previous activities in later life, c) having hobbies, d) having a physical or mental activity of some kind, and e) engaging in things one likes and finds meaningful.The typical answers were: "Successful ageing is to stay active, physically and mentally…", "to have something to do after retirement", "having some hobby, like gardening, fishing, or bowling", "not to give up on what you've been doing before").
One-third of the participants mentioned things that could be attributed to the social component.These responses were related to two subthemes: a) family and b) friendships and quality social life in general.The typical examples of quotes for the first subtheme were: "Successful ageing means harmony in the family", "support from the family", "spending time with grandchildren", "happy family", "love in the family" etc. Common examples of the second subtheme were: "hanging out with friends" or "when you have a quality social life".
The existential and financial security and stability component was mentioned by 24% of the participants.It included the subthemes of finances (e.g., "Successful ageing is….when you are financially secure, without any debts") and housing (e.g., "to live in one's own home", "to have a nice house").
The least mentioned component, cited by only 8% of the participants, was independence, divided into the subthemes: a) independence in performing activities of daily living and b) financial independence.The typical responses relating to the first subtheme were: when you are able to take care of yourself", "being able to get by without other people's help", while for the second subtheme they were: "not to depend financially on others", "when you have enough money for all you need and not need financial help from children".The independence in performing activities of daily living subtheme was closely related to the physical mobility subtheme of the physical/physiological component of SA and frequently co-occurred in participants' responses.However, the former focuses more on independence and the latter on maintaining physical mobility.The financial independence subtheme was also related to the finances subtheme within the existential and financial security and stability main theme.
The additional identified codes that rarely appeared in the descriptions of SA and were not closely related to the themes and subthemes described earlier were longevity, living in the countryside, peace and harmony in the world, previous work and life history, and listening to the advice of older people.

Contributing Factors/Determinants of Successful Ageing
The identified themes and subthemes, based on the codes derived from responses to the second question on contributing factors/determinants of SA, largely overlapped with those derived from responses to the first question on definitions and components of SA.Participants gave similar answers to both questions, although the answers to the second one were more concise and shorter (between 30 and 40 words long on average).They also included several different themes (listed in Table 2) per answer (three on average).Some of the participants even explicitly stated during the interview that they would answer the second question similarly to the first.Nevertheless, we decided to code and analyze the answers to the two questions separately because there were some differences in the answers to these two questions.We also wanted to distinguish the components of SA from the determinants as much as possible.
Our participants consider the social and physical determinants/contributing factors to be the most important for SA.
Social determinants, reported by 57% of participants, were categorized into three subthemes: a) family, b) friendships, and c) supportive social environment in general.Typical examples of family subtheme that appeared by far the most frequently in the responses were: "harmony in the family", "understanding and respect within the family" or "a good marriage".One male participant also said: "Family is the most important for a happy and fulfilled life.Without a family, a person would not be content and thus would not grow old successfully".Typical examples for the friendships subtheme were: "having good friends", "having social interactions with friends", and "having a good social life".One man answered: "…When you can go to a cafe with a friend, watch a game together, or take a walk in the park with him", and the other said: "…to have someone to talk to when you having a hard time, it would be easier for you".Typical responses for the supportive social environment subtheme were: "having a good social environment", "not being alone", "having company", "positive environment", or "being surrounded by good and positive people".
Physical factors (reported by 56% of respondents) were as important to participants as social factors.Physical factors were divided into almost identical subcategories as the physical components of SA in the response to the first question.These were: a) general health and physical functioning (e.g., "The health is by far the most important", "…being healthy", "…staying healthy"), b) healthy habits and lifestyle, health maintenance behaviours (e.g., "You need to eat healthily, sleep enough, stay physically active, walk in the fresh air ", " This would be a healthy diet, leaving behind bad habits or addictions, be it cigarettes, alcohol, or overeating"), and c) mobility and independence (e.g., being able to perform daily activities by oneself, such as doing household chores; for example, one woman said: "It is important to me that I can be as independent as possible in terms of my basic daily needs", while the other said: "to be able to go outside, to cook, to be able to clean the house").
Independence was not listed as a separate category, as it was in the responses to the first question about the components of SA.When it comes to contributing factors, independence was more related to maintaining physical mobility and overall physical functioning that allows the person to be independent and perform daily activities without assistance.
The category of psychological factors that could improve SA was also frequently mentioned (by 38% of participants).This was a very heterogeneous category that included various examples belonging to the subcategories of good life, subjective well-being, and various psychological resources.The typical examples of the good life subtheme were: "good", "normal" or "happy" life, and those related to subjective well-being in general were: "contentment", "peace of mind", "feeling good", "joy", "happiness", etc.Within the psychological resources subtheme, participants most frequently mentioned a "positive attitude" or "positive outlook" and "optimism".Besides, they usually mentioned themes related to successful stress management or stress avoidance, acceptance/adaptation to life changes, adaptation to difficulties in the ageing process, and acceptance/awareness of age-related limitations (e.g., "For successful ageing, the most important thing is not to worry, to live fully every day until the end of this earthly life, because life is beautiful and it is our own fault if it turns out differently.","…a state of consciousness in which a person realizes his limits and that he can no longer do what he used to be able to do").
Finances were also very important to our participants (cited by 30%) as facilitating factor in achieving SA.These included the subthemes of financial security and stability (e.g., having enough money, feeling financially secure, being financially stable) and financial independence (e.g., not being financially dependent on others or being able to meet one's needs financially).Some of the examples of the quotes are: "Finances, along with health, are crucial", "Successful ageing is easier if a person is financially stable, if he has enough for himself".
Although it was mentioned the least (i.e., by 24% of participants), the theme of engagement and activity also proved important.Within this theme, we actually identified six different subthemes.The most frequently represented subthemes were: being active in general, continuing to be active and engaged or continuing previous activities, having hobbies and quality leisure activities, and being physically or mentally active in general (e.g., "It's certainly easier when you have some kind of hobby, so you can occupy yourself with something during the day to make the time goes faster", "It is important to stay physically and mentally active").Less frequently mentioned were the subthemes of organizing daily activities and volunteering (e.g., "You have to organize your day -from getting up to going to bed", "Successful ageing is facilitated by….and by engaging in charity work").
We also identified some additional codes in the responses to the question about contributing factors of SA.These codes appeared very rarely and were not closely related to the themes described earlier.These were: longevity, good genes, listening to the advice of elders, living in the countryside (as less stressful), past life -how stressful and difficult it was, tolerance towards/understanding of young people whose lives are different today, enjoying good food, having a pet for company, and the global situation and peace in the world.
To the third question, whether they have aged successfully, almost all respondents answered 'yes' (n = 87; 92%).Only five participants answered 'no'.Two participants said that they have 'somewhat' successfully aged, and one participant answered that he could not rate.

Discussion
Since there is no research on the lay definitions of SA in Croatia and research on laypeople's understanding of SA is lacking in non-Western countries in general, we conducted a qualitative study to investigate how older people in the Republic of Croatia, a Southeastern European country, view SA and the factors contributing to it.Thematic analysis of responses from 95 community-dwelling older people, 65 to 90 years old, showed that the identified components of SA and contributing factors are similar to those identified in previous research on lay conceptions of SA in predominantly Western cultural contexts (Bowling, 2006;Bowling, 2007;Cosco et al., 2013;Jopp et al., 2015;Nosraty et al., 2015;Phelan et al., 2004;Reich et al., 2020;Reichstadt et al., 2007;Tate et al., 2003;Von Faber et al., 2001).Although the Republic of Croatia is a former communist and socialist country, it should be noted that after the transition period in the 1990s, it has increasingly followed individualistic values and a Western lifestyle in recent decades that could at least partly explain similarities between Croatian older people's perceptions of SA and those of older adults in Western countries.It is possible that in cultures that appreciate different values (e.g., collectivist versus individualist), perceptions of factors important to SA may be somewhat different.For example, Americans tend to underestimate the impact of external factors and emphasize individual responsibility for the success of the ageing process (Jopp et al., 2015).This may not be the case in collectivist cultures.On the other hand, it is possible that basic components/determinants such as good health and physical functioning, good social relationships, financial security, and psychological strengths are perceived to be similarly important to SA cross-culturally which may be another reason for observed similarities between Croatian people's definitions and Western definitions of SA.
Apart from some differences in the presentation of individual themes, respondents answered both questions (i.e., the first question about the components of SA and the second question about the things that contribute to or improve SA) similarly.This is another confirmation of the problem related to SA research, namely the conceptual confusion in the field of SA due to overlapping determinants and components of SA (Bowling, 2007;Cosco, 2015).Thus, we still cannot clearly distinguish between predictors and components of SA, as other authors also noted (Bowling, 2007;Cosco, 2015;Pruchno et al., 2010).It is also possible that people view the components and determinants of SA in a similar way because they are so interwoven that their integration may occur in such a way that some factors lead to SA (e.g., good physical functioning, engagement, or positive attitude) and then become its integral component.Nevertheless, we analysed the answers to the question on the definition of SA and answers to the second question on contributing factors separately in an attempt to distinguish between components and determinants/contributing factors of SA as much as possible.
Biomedical and psychosocial models, as well as the results of previous research on lay concepts of SA (Bowling, 2007;Cosco et al., 2013;Reich et al., 2020;Reichstadt et al., 2007;Reichstadt et al., 2010;Tate et al., 2003), indicate the great importance of factors related to physical health and functioning (in the biomedical model), psychological well-being and psychological resources such as selfacceptance, positive attitude, or coping mechanisms, and social factors such as good social relationships, support, and social engagement (in the psychosocial model) as components of SA or related factors.Accordingly, the results of this study also indicated a high presence of physical/physiological, psychological, and social factors as components as well as determinants of SA.However, in contrast to studies that have shown that older people place more importance on psychosocial factors such as social engagement and positive attitude, adjustment or self-acceptance, than on physical components (Cosco et al., 2013;Reich et al., 2020;Reichstadt et al., 2007), our study showed that the physical/physiological component was predominantly represented in lay definitions of SA.Along with social determinants, this was also the most represented category of identified determinants of SA.The physical component included similar subthemes in both definitions and determinants of SA /contributing factors.These included good general health, healthy habits and health maintenance behaviours, and mobility and ability to perform activities of daily living independently.Several other studies, some of which included not only older but also young and middle-aged adults, have also shown that health was most frequently cited as a basic resource for SA (Bowling, 2006;Jopp et al., 2015;Knight & Ricciardelli, 2003;Tate et al., 2003).
Nevertheless, our participants believe that more than physical health and functioning is required to age successfully.Thus, various psychological components were strongly represented.More specifically, they ranked second in definitions and third in the prevalence of identified categories of determinants of SA.This category of psychological components was very heterogeneous, but primarily included the subthemes of good, harmonious, and balanced life, subjective well-being (general satisfaction, happiness, peace of mind, no stress, etc.), and psychological resources (positive attitude, optimism, adjustment, acceptance of age-related changes, good coping strategies, etc.), as well as good cognitive functioning (good memory and preserved cognition in general) -as another identified subtheme within the category of cognitive and psychological components of SA.As noted earlier, psychological components such as well-being and psychological resources have also been shown to be important components or determinants of SA in many previous studies of lay concepts of SA (Bowling, 2006;Cosco et al., 2013;Jopp et al., 2015;Reich et al., 2020;Reichstadt et al., 2007;Reichstadt et al., 2010;Tate et al., 2003).Their importance, along with the importance of good social relationships, is emphasized in psychosocial models of SA (Bowling, 2007;Jeste et al., 2010) and in developmental models and theories that focus on adaptive mechanisms used across the lifespan, such as the model of selective optimization with compensation (Baltes & Baltes, 1990).
Social components were mentioned in the responses to the first question by about one-third of the participants.More specifically, they ranked fourth in the definitions of SA after physical/physiological, psychological, and engagement/ activity components.However, in addition to physical factors, social factors were most frequently cited as determinants of SA.Within the social component or social determinants of SA, subthemes related to good family relationships, friendships, and a good social life or supportive social environment in general were most frequently cited.These findings are consistent with previous research that also frequently reported social resources (Bowling, 2006;Cosco et al., 2013;Jopp et al., 2015;Knight & Ricciardelli, 2003;Reich et al., 2020;Reichstadt et al., 2007;Reichstadt et al., 2010).
Engagement and activity were another rather important component in our participants' lay definitions of SA (mentioned by 42%).On the other hand, 24% of participants mentioned it as a contributing factor.Within this component, the subthemes of general activity (e.g., being active, having something to do, working), continuing previous activities, having hobbies, and generally being physically and mentally active appeared most frequently in responses to both questions.In previous research, engagement and activity have also been identified by laypersons as very important to SA (Bowling, 2006;Cosco et al., 2013;Jopp et al., 2015;Knight & Ricciardelli, 2003;Reich et al., 2020;Reichstadt et al., 2007;Tate et al., 2003), but usually in the context of the social component, related to social engagement and community involvement.In our study, engagement/activity emerged as a distinct theme, separate from the more specific social component.We could say that the engagement/activity component partially reflects engagement with life as one of the three components of SA in Rowe and Kahn's (1998) influential model.It should be noted here that the subtheme of continuation of previous activities and lifestyle, which was frequently mentioned within the engagement/activity theme, supports Atchley's continuity theory (Atchley, 1989), which emphasizes the importance of continuing satisfactory previous activities and habits for maintaining well-being and quality of life in later years.At this point, we might say that our participants viewed SA in two ways, as a state of being or outcome assessed at a particular moment, but also as an ongoing dynamic process embedded in the overall individual life course, that is, as a process that has its roots in an earlier life history.
Twenty-three respondents (24%) emphasized the importance of existential and financial security and stability, including good finances and housing conditions, as components of SA.A slightly larger number of participants (30%) cited finances as an important factor facilitating SA, with the subthemes of financial security and stability and financial independence.Similarly, in a cross-cultural study of German and U.S. samples of young, middle-aged, and older adults, Jopp et al. (2015) found that finances were mentioned by about 30% of the sample.Interestingly, scientific theory on SA generally does not consider financial factors in relation to SA and tends to focus on personal resources and characteristics.On the other hand, financial and other external factors that influence quality of life recur in lay perceptions of SA, a reason why they should be considered in future research and theories of SA.
Ultimately, the theme of independence emerged as a distinct component of SA in the responses of the eight respondents.It related to the subthemes of independence in performing activities of daily living and financial independence.Independence also appeared in the responses to the second question, but was closely related to physical functioning and mobility factors.Therefore, it was categorized as a subtheme within the category of physical determinants of SA rather than a separate theme.Some other studies also frequently cited independence as a component or determinant of SA, usually referring to self-care and preserved abilities to perform activities of daily living or psychological strength (e.g., Bowling, 2007;Reich et al., 2020).Independence may be especially important to the oldest old, who are particularly concerned about continuing to live independently rather than being institutionalized (Nostary et al., 2015).
Interestingly, longevity and good genes were rarely mentioned as being associated with SA in our study (only by three participants).Apparently, older people consider the quality of life to be more important than simply living a long life.
Surprisingly, and in contrast to some models that include the dimension of spirituality (e.g., Young et al., 2009), no respondents directly mentioned spirituality or religiosity as important to SA.Rather, they focused on basic resources for SA such as physical health, social relationships, other psychological strengths (such as adjustment, positive attitude, optimism), and finances.Similarly, a recent review and cross-cultural comparison of lay perceptions of SA (Reich et al., 2020) reported that spirituality, along with cognitive health, was the least frequently detected component of SA.Even among the oldest old, who are thought to be more interested in coping with death through spirituality or religiosity, spirituality was a rarely mentioned topic (Nosraty et al., 2015).
To the third question, whether they have aged successfully, almost all participants (92%) answered 'yes', which is consistent with previous research showing that most older people rate their own ageing as successful (Jeste et al., 2010;Montross et al., 2006;Strawbridge et al., 2002).Although older people consider their physical health and functioning to be very important to SA, they are likely to meet their own subjective or psychosocial criteria of SA, i.e., they feel that they are satisfied with their lives, have good social relationships, and consider their lives to be meaningful.Therefore, they rate their ageing process as successful despite physical and functional limitations.This in turn supports the idea that SA is possible despite disease and disability (Strawbridge et al., 2002;Young et al., 2009).

Limitations
Finally, the shortcomings of the study should also be mentioned.They relate primarily to a convenience sample of community-dwelling older adults from different cohorts, which limits the possibility of generalizing the results to the entire Croatian older population or other groups of older people who were underrepresented in the study, such as frailer older people and people living in institutions.In addition, different categorizations of the themes identified by the thematic analysis were possible (e.g., grouping some related themes into one category), which would affect the results on the prevalence of the different themes.The study was conducted during the COVID -19 pandemic is still ongoing), so some people chose to participate in a telephone interview rather than a face-to-face interview.This may have affected the depth of participants' reflections on the questions or shorter, less detailed responses in some cases.
In addition, the small sample (although quite big for qualitative research) did not allow for more complex quantitative analyses, such as analysis of differences in lay views of SA in relation to sociodemographic characteristics such as gender, age, or education that may contribute to individual differences in the ageing process.Besides, these analyzes go beyond the scope of this study.

Conclusions
Despite the limitations mentioned above, it should be noted that, to our knowledge, this is the first study of lay perceptions of SA in Croatia and one of the few studies on this topic in non-Western European countries.The results of our study are consistent with the findings of previous research on SA in Western cultures, as our participants mentioned similar components/determinants of SA.Like much of the previous research on SA, these results also challenge the existing researchers' SA models by showing the great heterogeneity of lay conceptions of SA, which are much broader and more complex compared to the traditional SA models.Therefore, it could be suggested that these theoretical models should be extended to include more factors, which should improve their validity and practical utility.Additionally, this study confirmed that people do not sufficiently distinguish between components and determinants of SA, a problem that has also been recognized in quantitative research on SA (Cosco, 2015;Pruchno et al., 2010).However, further studies of lay conceptions of SA in other cultures that are underrepresented in research on lay views of SA, such as Asia, Africa, and Eastern Europe, are necessarily needed so that we can more confidently draw conclusions about cross-cultural similarities and differences of lay conceptions of SA.