Subjective Well-Being and Successful Ageing of Older Adults in Eastern Croatia—Slavonia: Exploring Individual and Contextual Predictors

Abstract

The process of population ageing with socioeconomic and political implications necessitates the creation of sustainable social strategies aimed at societal inclusion, support of subjective well-being and successful ageing of older adults. Therefore, the aim of this cross-sectional study was to explore individual and contextual factors and predictors which impede the possibility of successful ageing. The study was conducted from January to June 2024 through a questionnaire involving 403 elderly participants who live in the Eastern region of Croatia—Slavonia. The Diener Scale of Subjective Well-being and Self-assessment of Successful Ageing Scale were used in this research. A separate and model contribution of predictors (gender, age, subjective age, residence, level of education, marital status, comorbidities, Satisfaction with Life Scale and Prosperity Scale) were examined using bivariate and multivariate regression. Multivariate regression differentiated a statistically significant model, which as a whole explains between 41% and 55% of the variance of the present negative assessment of successful ageing, correctly classifying 80% of cases. The significant predictors included subjective age, place of residence, level of education, comorbidities, Satisfaction with Life Scale, and Prosperity Scale. These findings underscore the importance of both individual and contextual factors in successful ageing within this specific regional context.

1. Introduction

The phenomenon of an ageing population, also defined as demographic ageing, is increasing in proportion among individuals over the age of 60 and is the result of prolonged life expectancy of individuals and one of the base characteristics of the 21st century [1]. Prolonged life expectancy is a reflection of biomedical, social, and economic achievements of society [2]. The increase in life expectancy is particularly pronounced in high-income countries; however, it is evident in low- and middle-income countries as well. At the same time, projections indicate that by 2050, two-thirds of the elderly will live in the aforementioned countries, which confirms the global context of ageing research [3]. The population ageing process has economic, social, and political consequences [4] and challenges societies to create sustainable social strategies on global and individual levels. Therefore, this is the reason for a significantly heightened focus on research concerning the sustainability and concept of successful ageing [5].

At the individual level, ageing is dominantly observed as a physiological, gradual, and irreversible process marked by a decrease in tissue function and cellular activity, as well as a significant increase in the risks of various illnesses [6]. That being the case, prolonged maintenance of health and activity among the elderly is a priority as a strategy to provide an answer to population ageing [4]. Nevertheless, ageing is an individual biopsychosocial process conditioned by the individual’s genotypic and phenotypic personality expressed in different periods of life [7]. The aforementioned process is significantly influenced by the physical and socio-psychological environment (home, neighborhood, community) and the personal characteristics of the individual (gender, ethnicity, socioeconomic status) [8]. Therefore, in the continuation of the paper, features of individual and contextual factors in the ageing process which influence successful ageing and the subjective well-being of older adults are analyzed.

1.1. Subjective Well-Being

The concept of well-being is a multidimensional construct [9]. Components are psychological welfare, that is, the understanding of happiness derived from the realization of one’s own potential [10]; social welfare, which represents the evaluation of the individual’s well-being in a social context [11,12]; as well as subjective well-being, which is characterized by positive emotional functioning [13].

Subjective well-being is the extent to which a person perceives, believes, and/or feels that he or she is thriving in life [14] and consists of cognitive and affective components. The cognitive component refers to satisfaction with one’s own life. The affective component encompasses the balance of experiencing positive and negative effects [15].

In the context of cognitive and affective components of subjective well-being, it has been observed that the application of positive psychology interventions to elderly people results in improvements in memory, numerical abilities, self-confidence and the will to live. Conversely, exposure to negative contextual factors such as the perception of older people as confused, dependent and senile resulted in memory deterioration and feelings of worthlessness and uselessness among the observed elderly people [16].

The availability of biopsychosocial resources enables the development and progress of the individual and overall well-being [17]. Emphasis on the concept of well-being is fundamental to happiness and ageing [18], and well-being can be improved by supporting positive feelings, behavior and thoughts in older adults [19], commonly referred to as positive activities [20,21], which collectively contribute to successful ageing.

1.2. Successful Ageing

Successful ageing was researched using a biomedical and psychosocial approach. Within the biomedical approach, attention is focused on the absence of illness or a low probability of its occurrence, maintenance of physical and mental functioning at a high level, and an active involvement in life, which collectively represent attributes of the successful ageing model [22,23]. According to the psychosocial approach, for ageing to be successful, life satisfaction, optimal functioning within society, and psychological resources such as self-esteem, self-efficacy and autonomy are considered essential [5]. Moody and Sasser simultaneously state that the measure of successful ageing is a reflection of the level of life satisfaction and a sense of well-being in the face of decline [24].

However, elderly people describe successful ageing as significantly more complex compared to the assumed theoretical model [25], whereby numerous individual and contextual factors are highlighted. In addition to focusing on the attributes of the successful ageing model, sense of purpose and meaning in life, spirituality, learning new things, financial security, productivity, achievement, contribution to life, physical appearance, and sense of humor are considered significant [26]. However, when considering successful ageing and the factors that contribute to it, it is necessary to take life context into account because of its multifaceted and interconnected elements that surround older adults, shape their experiences, and the experience of ageing [8].

1.3. Sustainability and Successful Ageing in Eastern Croatia—Slavonia

A global shift in age distribution among the population according to the elderly [3] demands the creation of sustainable sociopolitical solutions, sustainable healthcare and social support systems [27], therefore requiring research into the factors which contribute to successful ageing and overall well-being of elderly people. According to the biomedical perspective, for successful ageing, active involvement in life is essential [22,23], thus making strategies focused on the inclusion of older adults as active participants in society indispensable [28]. However, the level of implementation of the aforementioned strategies depends on specific sociodemographic and economic factors as well as the level of development of the locality where the individual lives; therefore, the population from the locality of Eastern Croatia—Slavonia is included in the research due to the specific contextual factors.

Eastern Croatia—Slavonia, according to statistical and demographic parameters, has the most unfavorable dynamic demographic characteristics compared to other Croatian macroregions [29]. Because of the war and its consequences, inadequate economic resources, neglect of agricultural economic activity, substandard privatization, and poor political and economic management [30], it is the weakest developed Croatian macroregion [31]. According to projections, Eastern Croatia—Slavonia will have over one-third of elderly people over the age of 64 by 2050, and the share of young people will amount to 10–15% [29]. Demographic ageing in Slavonia at the societal level raises concerns about whether social arrangements are sustainable, since sustainability is defined as a situation in which individuals satisfy their needs without compromising the possibility for future generations to satisfy their needs [32,33]. Unsustainable social arrangements at the individual level influence the life context of older adults, addressing basic needs, subjective well-being, and the possibility of successful ageing [8,34].

The conducted research [35,36,37] states that contextual advantages/disadvantages such as advantages/disadvantages regarding socioeconomic status, availability of health care, and social inclusion at an individual level correlate with successful ageing. Thus, the current demographic situation in Eastern Croatia is an objective motive for the research of factors which contribute to or infringe upon the subjective well-being and possibility of successful ageing of the elderly.

Therefore, this study aimed to examine the separate and model contribution of individual (gender, age, subjective age, residence, level of education, marital status and comorbidities) and contextual factors (life satisfaction, prosperity, positive and negative experiences) as predictors of successful ageing on the elderly population who live in Eastern Croatia—Slavonia. Due to the extensive nature of research confirming the relationship between subjective well-being and successful ageing, this study contributes to the expansion of specific knowledge about these predictive values in the Croatian context, which can serve for improving social and communal sustainability.

Structurally, the paper has five chapters. After the first introductory chapter of the paper in which the definitions of subjective well-being and successful ageing are described, as well as the specific socioeconomic context of Eastern Croatia—Slavonia, the second chapter follows, where the methodology of data collection is described in detail, including study design, research instruments, statistical methods, and ethical considerations. In the third part of the paper, the results of the performed statistical analysis are presented in textual and tabular form. In the fourth chapter, the obtained results are compared and discussed with the results from other research. In the fifth part, relevant conclusions are drawn based on the conducted research, in which, based on the results of the conducted research and the results of other research, interventions are proposed to improve well-being and promote successful ageing.

2. Materials and Methods

Figure 1 presents the key activities of the study, which are described further below.

2.1. Study Design

This quantitative, cross-sectional study was conducted from January to June 2024 in participants’ homes, using non-probabilistic quota sampling to ensure equal distribution of respondents from urban and rural regions, given the importance of socio-environmental conditions on individual and contextual factors. The snowball technique was also employed in recruitment, as each participant was asked to assist researchers in identifying other potential subjects who met the inclusion criteria. Quota and snowball techniques were used simultaneously to enhance participant recruitment. All of the participants were informed in written form (through a research notice form) and verbally notified regarding the aim of the research, ethical issues, and instructions on filling out the survey. Participation in the research was voluntary, which they confirmed by signing the informed consent form. Anonymity was ensured while filling out the survey, as well as after the research by separating the survey and the informed consent form. The respondents were informed about the possibility of withdrawing from research participation at any given time. While filling out the survey, each respondent independently filled it out; in the case of difficulty in understanding individual questions, the information was clarified, but the researcher did not in any way suggest an answer or participate in the selection of answers. The time for completing the survey was not limited.

The conducted research is in accordance with the ethical principles outlined in the Declaration of Helsinki. Participation was voluntary and anonymous, and the participants were able to withdraw from research participation at any time. Written consent was obtained from the Higher Institution Ethical Committee (class: 602-01/24-12/02; IRB: 2158/97-97-10-24-36).

2.2. Participants

The participants were elderly people. The inclusion criteria were a chronological age of 60 and above, defined by the UN, which classifies persons over the chronological age of 60 and above as being elderly [38], the ability to give informed consent, and residence in the community, which means that participants who reside in institutionalized care facilities were excluded from the research.

Data were collected through anonymous surveys conducted in the participants’ households. Prior to sampling, the researchers received brief psychological and communication training from the Assistant professor of psychology and Associate professor of gerontology.

According to the criteria, the population was 403 with a minimum sample of 384, with a margin of error of 5% and confidence level of 95%. The population for calculation of criteria included 181,904 persons aged 60 and above in the Eastern region of Croatia—Slavonia. Population proportion was calculated with a Sample Size Calculator [39]. In the sample of a total of 403 participants, all of the respondents answered the question regarding gender, 175 of them (43.4%) identified as male, and 228 (56.6%) of the participants identified as female. None of the respondents chose the answer Other. The median age of the participants is 70, ranging from 60 to 92, and the median of subjective age (the age they feel, regardless of their actual age) is 65, ranging from 1 to 100.

In addition, we assessed whether the recommended sample size met the requirements for sufficient statistical power of 0.80 for the statistical tests used, including multivariate regression analysis (power of 0.95) [26]. The final sample (N = 403) was homogeneous (response rate: 82.96%).

2.3. Instrument

The research instrument involved general and sociodemographic questions in the introductory section of the survey (age, gender, place of residence, marital status, household income per person…) as well as validated surveys: the Diener Scale of Subjective Well-being: Satisfaction with Life Scale, Positive and Negative Experience Scale, and the Prosperity Scale [40], as well as the Self-assessment of Successful Ageing Scale [41]. Each of the scales included is described below.

The Diener Scale of Subjective Well-being—Satisfaction with Life Scale consists of five items which measure cognitive assessment of satisfaction with one’s own life (

Table A1. The Diener Scale of Subjective Well-being—Satisfaction with Life Scale. Skala zadovoljstva životom. Ispred Vas se nalaze određene tvrdnje koje se odnose na procjenu Vašeg života. Molimo Vas da što iskrenije odgovorite koliko se slažete ili ne slažete sa svakom od njih. Uz svaku tvrdnju označite odgovarajući broj. Koristite pri tome skalu na kojoj brojevi imaju sljedeća značenja: 1—uopće se ne slažem. 2—ne slažem se. 3—djelomično se ne slažem. 4—niti se slažem niti se ne slažem. 5—djelomično se slažem. 6—slažem se. 7—u potpunosti se slažem.

1.	U više aspekata moj život je blizak idealnom.	1	2	3	4	5	6	7
2.	Uvjeti moga života su izvrsni.	1	2	3	4	5	6	7
3.	Zadovoljan sam svojim životom.	1	2	3	4	5	6	7
4.	Do sada sam dobio/la sve važne stvari koje sam želio u životu.	1	2	3	4	5	6	7
5.	Kada bih ponovno živio svoj život, ne bih mijenjao/la gotovo ništa.	1	2	3	4	5	6	7

). The Scale contains seven scores (1—fully disagree, to 7—fully agree). The total result is the sum of the answers to the five statements with a theoretical range of 5 to 35. A higher score indicates greater satisfaction with one’s life.

The Diener Scale of Subjective Well-being—Scale of Positive and Negative Experience consists of twelve items distributed into two sub-scales which examine the assessment of experiences in the past four weeks (

Table A2. The Diener Scale of Subjective Well-being—Scale of Positive and Negative Experience. Skala pozitivnih i negativnih iskustava. Molimo Vas da razmislite o svojim iskustvima u posljednja četiri tjedna. Procijenite koliko često ste osjećali navedene emocije na skali od 1 do 5 pri čemu vrijedi: 1—vrlo rijetko ili nikad. 2—rijetko. 3—ponekad. 4—često. 5—vrlo često ili uvijek.

1.	Pozitivno	1	2	3	4	5
2.	Negativno	1	2	3	4	5
3.	Dobro	1	2	3	4	5
4.	Loše	1	2	3	4	5
5.	Ugodno	1	2	3	4	5
6.	Neugodno	1	2	3	4	5
7.	Sretno	1	2	3	4	5
8.	Tužno	1	2	3	4	5
9.	Preplašeno	1	2	3	4	5
10.	Radosno	1	2	3	4	5
11.	Ljuto	1	2	3	4	5
12.	Zadovoljno	1	2	3	4	5

Positive Experience: 1, 3, 5, 7, 10, 12. Negative Experience: 2, 4, 6, 8, 9, 11.

). Six items examine positive feelings, while the other six items examine negative feelings. The Scale contains five scores (1—rarely or never, to 5—very often or always). The result of both sub-scales may vary from 6 to 30. It is possible to subtract the result of positive experiences from the result of negative experiences (the results may vary from −24 to 24).

The Diener Scale of Subjective Well-being—Prosperity Scale consists of eight items which describe important aspects of human function (

Table A3. The Diener Scale of Subjective Well-being—Prosperity Scale. Skala prosperiteta. Molimo Vas da na skali od 7 stupnjeva procijenite koliko se slažete s navedenim tvrdnjama. 1—uopće se ne slažem. 2—ne slažem se. 3—djelomično se ne slažem. 4—niti se slažem niti se ne slažem. 5—djelomično se slažem. 6—slažem se. 7—u potpunosti se slažem.

1.	Vodim svrhovit i smislen život.	1	2	3	4	5	6	7
2.	Moji odnosi s drugima su podržavajući i nagrađujući.	1	2	3	4	5	6	7
3.	Angažiran/a sam i zainteresiran/a za svoje dnevne aktivnosti.	1	2	3	4	5	6	7
4.	Aktivno doprinosim sreći i dobrobiti drugih.	1	2	3	4	5	6	7
5.	Kompetentan/na sam i sposoban/na u aktivnostima koje su mi važne.	1	2	3	4	5	6	7
6.	Dobra sam osoba i živim dobar život.	1	2	3	4	5	6	7
7.	Optimističan/na sam glede svoje budućnosti.	1	2	3	4	5	6	7
8.	Ljudi me poštuju.	1	2	3	4	5	6	7
9.	Vodim svrhovit i smislen život.	1	2	3	4	5	6	7
10.	Moji odnosi s drugima su podržavajući i nagrađujući.	1	2	3	4	5	6	7

). The Scale contains seven scores (1—fully disagree, to 7—fully agree). The total result is the sum of all assessments. It may vary from 8 to 56. A higher score indicates a higher perception of success in important areas of functioning such as relationships, self-esteem, purpose, and optimism. It was designed to measure social–psychological prosperity and to complement existing measures of subjective well-being [40].

The Self-assessment of Successful Ageing Scale consists of twenty items which examine the assessment of one’s own ageing experience (

Table A4. The Self-assessment of Successful Ageing Scale. Skala samoprocjene uspješnog starenja. Molimo Vas da procijenite koliko se svaka od dolje navedenih tvrdnji odnosi na Vas osobno. Pri tome koristite skalu na kojoj brojevi imaju sljedeće značenje.

	1	2	3	4	5
	uopće se NE odnosi na mene	uglavnom se NE odnosi na mene	niti se odnosi, niti se ne odnosi na mene	uglavnom se odnosi na mene	u potpunosti se odnosi na mene
1.	Mislim da ću živjeti vrlo dugo.				1	2	3	4	5
2.	Dobroga sam zdravlja.				1	2	3	4	5
3.	Zadovoljan/na sam svojim životom većinu vremena.				1	2	3	4	5
4.	Imam gene (naslijeđe) koji mi pomažu da dobro starim.				1	2	3	4	5
5.	Imam prijatelje i obitelj koji su tu zbog mene.				1	2	3	4	5
6.	Uključen/na sam u svijet i ljude koji me okružuju.				1	2	3	4	5
7.	Sposoban/na sam odabrati stvari koje se tiču mog starenja, kao što su prehrana, vježbanje i pušenje.				1	2	3	4	5
8.	Sposoban/na sam postići sve ono što trebam i nešto od onoga što želim.				1	2	3	4	5
9.	Ne osjećam se usamljeno ili izolirano.				1	2	3	4	5
10.	Uspješno se prilagođavam promjenama koje su povezane sa starenjem.				1	2	3	4	5
11.	Sposoban/na sam brinuti se o sebi.				1	2	3	4	5
12.	Imam osjećaj mira kada razmišljam o tome da neću živjeti vječno.				1	2	3	4	5
13.	Imam osjećaj da sam bio/bila sposoban/na utjecati na tuđe živote na pozitivan način.				1	2	3	4	5
14.	Ne žalim za načinom na koji sam proveo/la svoj život.				1	2	3	4	5
15.	Radim na plaćenim ili volonterskim aktivnostima nakon uobičajene dobi za umirovljenje.				1	2	3	4	5
16.	Osjećam se dobro sa samim sobom.				1	2	3	4	5
17.	Sposoban/na sam uspješno se suočiti s promjenama u svojim kasnijim godinama.				1	2	3	4	5
18.	Ne bolujem od kroničnih bolesti.				1	2	3	4	5
19.	Nastavljam učiti nove stvari i u kasnijim godinama.				1	2	3	4	5
20.	Sposoban/na sam djelovati u skladu s mojim standardima i vrijednostima.				1	2	3	4	5

). The Scale contains five scores (1—does not apply to me at all, to 5—fully applies to me). The total result is the average value of the sum of the assessments, which may vary from 20 to 100. A higher score indicates a more favorable perception of one’s own ageing as more successful [41].

2.4. Statistical Methods

Categorical data are represented with absolute and relative frequencies. The normality of the distribution of continuous variables was tested using the Shapiro–Wilk. Data were found to be of non-normal distribution, leading to the use of non-parametric statistics. Continuous data are described by the median and the limits of the interquartile range. Differences in the continuous variables between the two independent groups were tested with the Mann-Whitney U test. The participants were divided into two groups according to the median score of successful ageing (median 69). The correlation score was given by the Spearman correlation coefficient ρ (Rho). Logistic regression, bivariate and multivariate (Stepwise method), evaluated the influence of several factors on predicting a negative assessment of successful ageing [42,43].

All p values are two-sided. The level of significance is set at alpha = 0.05. For statistical analysis, the statistical package MedCalc^® Statistical Software version 22.023 (MedCalc Software Ltd., Ostend, Belgium; https://www.medcalc.org; 2024) and SPSS 23 (IBM Corp. Released 2015. IBM SPSS, Ver 23.0. IBM Corp., Armonk, NY, USA) were used. The report on the conducted research adhered to the guidelines for reporting the results of research in biomedicine and healthcare [44].

3. Results

A total of 403 individuals participated in the study, with 228 (56.6%) identifying as female and 175 (43.4%) as male. The average age of the participants was 65.4 years. Notably, the men in the study were on average older, with an average age of 66.87 years, compared to 64.8 years for women (

Table 1. Basic characteristics of the participants.

Category	Variable		Result
Gender	Male	N (%)	175 (43.4)
	Female		228 (56.6)
Age	Chronological age	[Mdn (IQR)]	70 (67–77)
	Subjective age		65 (55–70)
	Difference in subjective and chronological age		−8 (−16 to 8)
Category of subjective age	Feel younger than actual age	N (%)	286 (71.0)
	Feel their actual age		69 (17.1)
	Feel older than actual age		48 (11.9)
Place of residence	City/suburban settlement	N (%)	202 (50.1)
	Village		201 (49.9)
	Elementary school education	N (%)	172 (42.7)
Level of education	High school education		183 (45.4)
	Post-secondary education		47 (11.7)
	Doctorate degree		1 (0.2)
	Married	N (%)	210 (52.1)
	Divorced		33 (8.2)
Marital status	Widowed		127 (31.5)
	In a relationship		7 (1.7)
	Single		26 (6.5)
Comorbidities	Suffer from chronic illness	N (%)	206 (51.1)

).

Looking at the difference between one’s actual age and one’s feeling old regardless of their actual age, the median is −8 (interquartile range −16 to 0 years) in the range of −78 to 31 years. That is, 286 (71%) respondents reported feeling younger than their actual age, 69 (17.1%) feel as old as their actual age, while 48 (11.9%) state that they feel older than their actual age. With respect to residence, 202 participants (50.1%) live in a city/suburban settlement. Regarding the level of education, 183 (45.4%) had completed secondary education. Concerning marital status, 210 (52.1%) respondents are married, and 127 (31.5%) are widowed. With regard to health issues, 206 (51.1%) respondents suffer from chronic illnesses.

Measures of the mean and dispersion of subjective well-being indicate a median score of 23 on the life satisfaction scale and a median of 41 on the prosperity scale, while on the scale of positive experiences, the median is 22, and the subscale of negative experiences is 16. The median difference between negative and positive experiences is −6, with a range from −24 to 16. Self-assessment of successful ageing yielded a median score of 69, ranging from 24 to 100. According to the median score of successful ageing (median 69), a total of 199 (49.4%) respondents perceived their ageing as successful (

Table 2. Measures of the mean and dispersion of subjective well-being, and the self-assessment of successful ageing.

	Median  (Interquartile Range)	Range from Minimum to Maximum
Subjective well-being
Life satisfaction scale	23 (18–27)	5–35
Prosperity scale	41 (34–48)	12–56
Positive experiences	22 (19–25)	9–30
Negative experiences	16 (12–20)	6–30
Scale of negative and positive experiences (negative—positive)	−6 (−11 to 0)	−24 to 16
Self-assessment of successful ageing scale	69 (61–76)	24–100

).

There is no significant difference in the self-assessment of successful ageing in relation to gender, with men expressing a self-assessment of successful ageing with a median of 69, and women 70 (p = 0.38) (

Table 3. Self-assessment of successful ageing in relation to gender.

	Median (Interquartile Range)		p *
	Men	Women
Self-assessment of successful ageing scale	69 (61–75)	70 (60.3–78)	0.38

* Mann Whitney U test.

).

The respondents who live in a village, in comparison to the respondents who live in a city/suburban settlement, rated the self-assessment of successful ageing scale significantly lower (Mann Whitney U test, p < 0.001) (

Table 4. Self-assessment of successful ageing in relation to place of residence.

	Median (Interquartile Range)		p *
	City/Suburban Settlement	Village
Self-assessment of successful ageing scale	72 (64–78)	67 (58–75)	<0.001

* Mann Whitney U test.

).

The older the respondents are, the worse the self-assessment of successful ageing scale is rated, and the older the subjects feel (positive difference between how old they feel and their actual age), the worse the score of successful ageing is (Rho = −0.305) (

Table 5. Correlation of the age of the respondents and the difference between the estimated and actual age with the self-assessment of successful ageing.

	Spearman’s Correlation Coefficient Rho (p Value)
	Age of Respondent	Difference between Subjective and Actual Age
Self-assessment of successful ageing scale	−0.145 (<0.001)	−0.305 (<0.001)

).

The probability of a lower rating of successful ageing is influenced by: the older age of the respondents (OR = 1.03), the feeling that they are older than their real age (OR = 1.03), living in the village compared to respondents who live in the city (OR = 1.99), being divorced (OR = 2.16) or widowed (OR = 1.56) compared to respondents who are married, the presence of comorbidities (OR = 2.61), and the prevalence of negative experiences in the total scale of negative and positive experiences (OR = 1.11). Predictors which reduce the probability of lower scores on successful ageing include a higher level of education compared to a lower level of education (OR = 0.41), greater life satisfaction (OR = 0.76), better prosperity scale ratings (OR = 0.84), and stronger expression of positive experiences (OR = 0.76).

All predictors significant in the bivariate regression were included in the model as independent predictors. Six independent predictors made a unique statistically significant contribution to the model predicting poorer ratings of successful ageing. The model is statistically significant in its entirety (χ² = 215.4, p < 0.001), and as a whole explains between 41% (according to Cox & Snell R²) and 55% (according to Negelkerke R²) of the variance of the present negative assessment of successful ageing, correctly classifying 80% of cases.

For a worse evaluation of successful ageing, the following have a higher chance: 1.03 times respondents who feel older than they are (OR = 1.03); 2.49 times respondents living in the countryside (OR = 2.49); 2.07 times respondents with a lower level of education compared to respondents with a higher level of education (OR = 2.07); and 1.86 times a greater chance for a worse assessment of successful ageing among respondents who have comorbidities (OR = 1.86). A higher score on life satisfaction (OR = 0.85) and a higher score on the prosperity scale (OR = 0.89) reduce the probability of a lower score on successful ageing (

Table 6. Predicting the probability of negative scores on successful ageing.

		β	Wald	p	Odds Ratio (OR)	95% Confidence Interval
Individual factors	Gender	−0.09	0.24	0.63	0.91	0.61 to 1.35
	Age	0.03	5.05	0.02	1.03	1.004 to 1.07
	The difference between the subjective age and the chronological age	0.03	13.3	<0.001	1.03	1.02 to 1.06
	Residence (village vs. city/suburb)	0.69	11.7	<0.001	1.99	1.34 to 2.97
	Level of education (higher vs. secondary school)	−0.89	6.64	0.01	0.41	0.21 to 0.81
	Marital status
	divorced	0.77	3.95	0.04	2.16	1.01 to 4.62
	widowed	0.45	3.91	0.04	1.56	1.02 to 2.44
	Comorbidities	0.96	21.9	<0.001	2.61	1.75 to 3.91
Contextual factors  (subjective well-being)	Life satisfaction scale	−0.27	91.9	<0.001	0.76	0.72 to 0.81
	Prosperity scale	−0.17	94.2	<0.001	0.84	0.81 to 0.87
	Positive experiences	−0.28	74.2	<0.001	0.76	0.71 to 0.81
	Negative experiences	0.04	3.17	0.08	1.04	0.99 to 1.08
	Scale of negative and positive experiences  (neg—pos)	0.10	41.3	<0.001	1.11	1.07 to 1.14
Model for predicting the negative rating of successful ageing	The difference between the subjective and chronological age	0.03	7.91	0.005	1.03	1.01 to 1.05
	Residence (village vs. city/suburb)	0.91	10.23	0.001	2.49	1.42 to 4.37
	Level of education (secondary school)	0.73	6.45	0.01	2.07	1.18 to 3.61
	Comorbidities	0.62	5.24	0.02	1.86	1.09 to 3.17
	Life satisfaction scale	−0.16	25.3	<0.001	0.85	0.80 to 0.90
	Prosperity scale	−0.12	26.9	<0.001	0.89	0.85 to 0.93
	Constant	7.75	67.8	<0.001

β—regression coefficient.

).

4. Discussion

Until two decades ago, the focus of research in the area of ageing was predominantly on chronic illnesses, physical and mental functional limitations in the older stage of life. The results of previous research indicate that focusing on the negative aspects of ageing negatively correlates with self-assessment of successful ageing. For instance, continual emphasis on the appearance of physical changes in the older stage of life can consequently create a negative self-perception of ageing among individuals [45,46]. Self-perception of ageing and the attitude towards one’s own ageing are important for successful ageing. Through the development of modern approaches to ageing which emphasize the positive aspects of functioning in the older stage of life, the concept of successful ageing becomes increasingly significant and the topic of numerous scientific studies [47,48].

The concept of successful ageing is marked by the absence of illness or a low probability of its occurrence, maintenance of physical and mental functioning at a high level, and an active involvement in life. Important determinants of successful ageing are life satisfaction, optimal functioning within society, and psychological resources such as self-esteem, self-efficacy, and autonomy [22].

The self-assessment of successful ageing results do not indicate the existence of differences considering gender, consistent with the results by Carver and Beamish [49], while Susanti et al. [50] and Shi [51] suggest that male respondents report higher levels of self-assessment of successful ageing, possibly due to greater access to social resources and, in certain sociocultural contexts, higher socioeconomic status compared to female respondents. The significance of this is confirmed by Shi et al., who state that socioeconomic factors are significantly and highly associated with individuals’ odds of successful ageing [51].

Divorced people and widowers report more negative scores on successful ageing. Given that marital partners sometimes represent each other’s only company, if at some point one of the partners is left alone due to the death of the other partner or a divorce occurs, the probability of feeling lonely in an elderly person due to the newly created situation is greater. Considering loneliness and marital status, Solić et al. found a significant positive correlation with intimate status, indicating that individuals who are single (widowed, divorced or unmarried) experience greater loneliness than individuals who have a partner [52]. These results are consistent with Kislev, which states that older adults who are married are on average happier and less lonely [53]. Considering the social dimension of loneliness, older adults who are married and/or have children show a higher level of successful ageing in their self-assessment, which is interpreted through the dimension of family social support existence at the level of parents and children [54,55]. Although the quality of marital relationships was not assessed in this research, loneliness is more common in marriages whose quality was rated as low [56], which points to the significance of family unions and the quality of social relationships in the context of successful ageing.

The study identified six predictors significantly contributing to the lower perception of successful ageing, with 55% of the negative evaluation of successful ageing criterion being explained. Due to the examination of negative assessment, identified predictors present a main point for psychosocial intervention with the aim of reducing their impact on the achievement of successful ageing. These predictors are described in detail later in the text.

4.1. Comorbidities

The results of this research indicate that the probability of lower scores on the successful ageing scale is impacted by the older age of the respondents (OR = 1.03), which is consistent with the results of previous studies indicating that older age is connected to a higher probability of lower scores on the successful ageing scale [57,58,59]. This can be explained by the higher probability of decreased tissue function and cellular activity as well as a significant increase in the risk of various illnesses related to ageing (neurodegenerative, cardiovascular and metabolic diseases, as well as diseases of the immune and musculoskeletal systems) [6], which is in accordance with the conducted research results, whereby 51.1% of the respondents suffer from at least one chronic disease. As a result, there may be a higher level of dependence on other people, which at the same time reduces the possibility of making one’s own decisions among elderly people [59]. This can ultimately lead to dissatisfaction, frustration and finally a lower level of quality of life.

4.2. Level of Education

A higher/high level of education is a predictor that reduces the probability of a negative self-assessment of successful ageing (OR = 0.41), which agrees with previous research whose results indicate that a higher level of education is associated with a higher probability of a more positive assessment of successful ageing [60,61]. A higher level of education enables a higher possibility of employment along with a safer and higher-paid workplace with the projection of better financial status after retirement, all contributing to higher life satisfaction. The appearance of health problems among people with a lower socioeconomic status was observed, which correlates with a lower level of education [62]. According to authors Lantz PM and Marmot M, elderly people with a lower level of education have limited access to health resources, correlating with less favorable health outcomes [63,64]. In addition, several studies indicate that a higher level of education is associated with healthy ageing [65,66,67]. In that context, healthy ageing can be observed as one of the prerequisites for successful ageing considering the attribute of successful ageing, which is the absence of illness and infirmity. According to the above, it is assumed that a higher level of education enables the reduction of negative individual and contextual factors that reduce the chances of successful ageing.

4.3. Place of Residence

The results of this research indicate that elderly people who live in a village or suburban settlement give lower scores on successful ageing in relation to the respondents who live in a city (OR = 1.99). Accordingly, there are studies which indicate that the population that gravitates towards rural locations has a lower level of education, a lower rate of household income, and a lower rate of employment [68]. Apart from the aforementioned social factors, the availability of health care is of significant importance. There are a lower number of healthcare institutions in rural areas compared to urban areas; at the same time, it takes more time for transportation to certain healthcare institutions in case of the need for certain medical-technical interventions, and in addition to all of this, there are poorer traffic connections [69]. As a result, the consequence of limited access to health care is reduced access to healthcare services, which can ultimately lead to poorer health outcomes [70,71].

4.4. Subjective Age

The results indicate that the likelihood of lower scores on successful ageing is influenced by an older subjective age (OR = 1.03). The results of a meta-analysis, which included more than 45,000 individuals, found that older subjective age is correlated with a more negative assessment of subjective well-being, worse cognitive outcomes, and increased depressive symptoms [72]. In addition, an older subjective age correlates with an increased risk of mortality [73]. Considering this, subjective age may have a motivating/demotivating effect on elderly people. For instance, a younger subjective age may prompt a higher motivation to work [74] and younger patterns of behavior which will ultimately positively contribute to health [75]. A younger subjective age is in correlation with a higher degree of subjective well-being, better health, and lower risk of mortality [72,76,77].

4.5. Life Satisfaction and Prosperity

Higher scores on life satisfaction (OR = 0.85) and on the Prosperity scale (OR = 0.89) decrease the probability of lower scores on successful ageing. Although research shows that physical health and level of functionality at an older age are relevant factors in self-assessment of life satisfaction and well-being, elderly individuals can feel happiness, satisfaction, and well-being regardless of certain difficulties by compensating for them using positive psychosocial resources [78]. Each stage in an individual’s life is marked by certain changes to which he or she needs to adapt. Therefore, by accepting the fact that certain changes will occur with ageing, through the development of compensatory mechanisms and ultimately by adequate adaptation to ageing, the basis for well-being, satisfaction and prosperity in the life of the individual is ensured. According to Izal, Nuevo and Montorio [79], positive psychology and successful ageing seem to be intrinsically related theoretical contexts. This postulates the need to create interventions based on positive psychology as one of the new ways of promoting successful and healthy ageing that can also contribute to life satisfaction.

4.6. Study Limitations and Recommendations

While this research offers several advantages, including the use of representative samples and the identification of predictors for successful ageing, certain limitations must be acknowledged. First, the cross-sectional study was conducted where it is possible to identify the connection between and prediction of the probability of certain behaviors, but it is not possible to identify the cause. Second, the research was conducted in a continental region of the Republic of Croatia with a specific sociocultural environment, which disenables generalization at the level of society. Third, data were collected with a validated survey; however, the probability of giving socially acceptable answers is stated as a drawback of the survey research. Efforts were made to mitigate this by educating participants beforehand and ensuring anonymity during the survey. In addition, during the collection of data, it was not possible to exclude transitory socioeconomical influences which could have potentially momentarily undermined the self-assessment of successful ageing. An attempt was made to minimize this by inquiring whether the participants had gone through personal or family events in the past six months that potentially, transiently, or momentarily influenced their perception of success of the ageing process. Therefore, the first recommendation for future research is to use the Mini Mental State Examination (MMSE) as a criterion for psychological assessment along with an evaluation of the influence of acute negative emotional events [80]. Second, expanding the participant pool to include other regions and employing a longitudinal design would enhance the understanding of changes in self-assessment of successful ageing over time. The third recommendation is to conduct a qualitative examination of identified predictor factors to investigate the nature of the causality of individual predictors in their contribution to the self-assessment of successful ageing.

5. Conclusions

In this study, six independent predictors were identified: subjective age, comorbidities, level of education, place of residence, life satisfaction, and prosperity, which made a unique statistically significant contribution to the model predicting poorer ratings of successful ageing. Ageing of the population as one of the most significant demographic changes in modern society requires timely social institutional reactions. Therefore, the identified predictive values of subjective well-being in the prediction of successful ageing in the context of Eastern Croatia—Slavonia can serve in designing strategies which will increase the possibility of successful ageing. Considering the identified contribution of individual and contextual factors to successful ageing, recommended interventions which may influence identified individual and contextual factors follow [81,82].

Due to the significant increase in health problems related to ageing, it is important to provide adequate health care, information about the importance of healthy nutrition and physical activity, as well as allow for the expression of opinions and feelings connected to health and well-being. In addition, it is essential to promote social inclusion of the elderly along with an individual approach to each person and assess the level of functional abilities, which ultimately depends on the extent to which the elderly can truly be socially included, participate in various activities, and use services intended for the elderly stage of life. Through estimation, one may suggest a type of social activity which is adequate for a certain individual. In addition, it is important to reach out to an individual who is in isolated areas and has limited access to the social community and ensure available transportation. Including them in clubs and organizations for older people can contribute to a higher level of satisfaction because it gives them a chance to talk, to exchange experiences, and to create new social relationships. Finally, it is necessary to emphasize the importance of using digital technology, which enables elderly people greater social inclusion and access to various information which can enrich their knowledge through new ways of communication.