Intention to Retire in Employees over 50 Years : What is the Role of Work Ability and Work Life Satisfaction?

International Journal of Environmental Research and Public Health Article Intention to Retire in Employees over 50 Years. What is the Role of Work Ability and Work Life Satisfaction? Prakash K.C. 1,2,*, Jodi Oakman 3, Clas-Håkan Nygård 1,2, Anna Siukola 1,2, Kirsi Lumme-Sandt 1,2, Pirjo Nikander 2,4 and Subas Neupane 1,2 1Unit of Health Sciences, Faculty of Social Sciences, Tampere University, Arvo Ylpönkatu 34, 33520 Tampere, Finland 2Gerontology Research Center, Tampere University, FI-33014 Tampere, Finland 3Centre for Ergonomics and Human Factors, School of Psychology and Public Health, La Trobe University, Melbourne, VIC 3086, Australia 4Faculty of Social Sciences, Tampere University, FI-33014 Tampere, Finland *Correspondence: [email protected] or [email protected]; Tel.: +358-443111531 Received: 27 June 2019; Accepted: 11 July 2019; Published: 13 July 2019   Abstract: Background: We investigated work ability and trajectories of work life satisfaction (WLS) as predictors of intention to retire (ITR) before the statutory age. Methods: Participants were Finnish postal service employees, who responded to surveys in 2016 and 2018 (n =1466). Survey measures included ITR, work ability and WLS. Mixture modelling was used to identify trajectories of WLS. A generalized linear model was used to determine the measures of association (Risk Ratios, RR; 95% Confidence Intervals, CI) between exposures (work ability and WLS) and ITR. Results: Approximately 40% of respondents indicated ITR. Four distinct trajectories of WLS were identified: high (33%), moderate (35%), decreasing (23%) and low (9%). Participants with poor work ability (RR 1.79, 95% CI 1.40–2.29) and decreasing WLS (1.29, 1.13–1.46) were more likely to indicate an ITR early compared to the participants with excellent/good work ability and high WLS. Job control mediated the relationship between ITR and work ability (9.3%) and WLS (14.7%). Job support also played a similar role (14% and 20.6%). Conclusions: Work ability and WLS are important contributors to the retirement intentions of employees. Ensuring workers have appropriate support and control over their work are mechanisms through which organisations may encourage employees to remain at work for longer. Keywords: intention to retire; work ability; ageing workers; work wellbeing; psychosocial work exposures 1. Introduction An ageing population will require extended working lives in comparison to previous generations to ensure an adequate labour supply and financial resources for retirement [ 1 ]. Many countries have instigated initiatives to encourage people to delay their retirement, but with mixed success [ 2 ]. Retirement choices are complex [ 3 ] and influenced by a range of factors (financial incentives to retire early, poor health and working conditions), which require comprehensive exploration to inform strategies to assist with retaining employees [ 3 , 4 ]. Older workers vary significantly in their physical and mental capacities and, as a result, a nuanced approach to retirement age may better ensure that participation rates remain high for a broad range of employees in different occupations. Meanwhile, however, a broader understanding is needed to inform organizations about the influences they have on their employee’s retirement intentions [5]. Int. J. Environ. Res. Public Health 2019,16, 2500; doi:10.3390/ijerph16142500 www.mdpi.com/journal/ijerph Int. J. Environ. Res. Public Health 2019,16, 2500 2 of 13 Job satisfaction is a complex issue, and the particular aspects of work that influence an individual’s overall satisfaction vary. Furthermore, the relative importance of different aspects that influence job satisfaction have been demonstrated to vary over the life course and have been shown to influence intention to retire (ITR) [ 6 , 7 ]. The key challenge for the debate on ITR, therefore, is to fully understand the dynamics surrounding a person moving toward retirement age and the job satisfaction factors that have been demonstrated to change and influence the decision to stay in employment or retire. Sufficient support at work and high level of work satisfaction have been identified as important factors in decisions relating to retirement [ 8 ]. Similarly, using longitudinal data, von Bonsdorffand colleagues (2010) reported that employees with lower work life satisfaction were more likely to indicate an earlier intention to retire [ 9 ]. A Dutch study found higher levels of work engagement as associated with a delayed ITR among employees of an older age group [10]. A further predictor of ITR early is poor work ability [ 7 , 9 , 11 – 13 ]. Work ability concerns the capacity to manage job demands in relation to physical and psychological resources. Work ability at mid-life has been found to predict early retirement due to disability, supporting the need for a life-course approach to sustainable employment. A number of longitudinal analyses of populations have consistently reported that poor work ability is linked with higher risk of early retirement in comparison to those with good or excellent work ability [11–13]. Working conditions are an important contributor to the decision-making process on the timing of retirement [ 9 , 14 – 16 ]. For some workers in physically demanding work, an extended working life is challenging, and early exits are common occurrences [ 9 , 14 ], often ending with a disability pension [ 17 ]. In addition to the physical environment, psychosocial working conditions have also been identified as an important influence on whether an employee will choose to stay or leave work before the mandated retirement age [ 18 – 20 ]. A study of Finnish social and health care employees by Elovainio and colleagues (2007) reported that job demand and job control was correlated to early retirement thoughts [ 21 ]. Likewise, a study among Danish employees aged ≥ 50 years reported that lack of possibilities for development at work was an important factor to induce early retirement thought [ 19 ]. Similarly, low job control predicted exiting paid employment among employees aged 50–63 years in 11 European countries [ 22 ]. Furthermore, the support at work offers a way to manage work ability among employees and a platform for discussion and planning of their workload. High levels of support at work has been reported to be associated with considerations about retirement intentions [8]. The aim of encouraging working beyond retirement has been of interest to many industrialized nations. The challenge at a workplace is to prevent early retirement among workers and ensure participation until statutory retirement age, which requires further insights into the role of organizations in retaining workers for longer. Work-related factors and work ability are important contributors of ITR before statutory age, however the role of these factors and possible mediating effects have not yet been explored. To contribute to this important area, the current study aimed to investigate work ability and work life satisfaction as predictors of ITR among the employees aged over 50 years. In addition, the potential mediators of the association between psychosocial exposures and ITR were investigated. 2. Materials and Methods 2.1. Participants and Design The data for this study were derived from “Towards a Two-Speed Finland Survey (2tS)”, collected from employees of the Finnish postal service, which is a large national public sector company with approximately 20,000 employees. The baseline 2tS was conducted in 2016 (n =2096, 44% response rate) among all the workers aged ≥ 50 years who did not explicitly deny receiving a call to participate in a survey. The follow up survey was completed in 2018, with a 70% response rate from baseline respondents, n =1466. We used a follow up survey in the present study. The ethical approval for the study was provided by the Academic Ethics Committee of Tampere Region (Tampere University, approval number: 32/2016). Int. J. Environ. Res. Public Health 2019,16, 2500 3 of 13 2.2. Measures 2.2.1. Intention to Retire (ITR) Intention to retire (ITR) indicates intention to retire before the statutory retirement age. The statutory retirement age in Finland is 65 years. ITR was measured through two questions. The first “Will you be able to work until statutory retirement age?” with a five point Likert scale: “totally true”, “somewhat true”, “not exactly true”, “not true at all” and “cannot say”. Responses were dichotomized into yes (“totally true” and “about true”) and no (“not exactly true” and “not true at all”). The second question “Have you thought you might retire due to health or other reasons before statutory retirement age?” was measured on a four point Likert scale: “not thought”, “thought sometimes”, “thought often”, “filed application already”. Responses were similarly dichotomized into no (“not thought”) and yes (“thought sometimes”, “thought often” and “filed application already”). Dichotomized responses were matched and used as a single item with “yes” (responding “yes” in both questions) and “no” response. The development of this variable was adapted from previous research [23,24]. 2.2.2. Satisfaction in Working Life (WLS) The satisfaction with working life (WLS) was assessed retrospectively for the following time periods: “15–29”, “30–39”, “40–49”, “50–59” and “60–69” years of age. Responses were collected on a scale from 0 (very dissatisfied) to 10 (very satisfied). As most respondents were 50–59 years of age, the question regarding WLS during “60–69” years of age was excluded. Responses on WLS at “15–29”, “30–39”, “40–49”, “50–59” years were used to detect the trajectories of WLS. The measure of WLS using a single item has been previously validated [25]. 2.2.3. Work Ability Work ability was assessed using a single item [ 11 ]. Respondents were asked to rate their current work ability compared to their life’s best using a scale of 0–10, where “0” indicated the worst and “10” indicated the best work ability [ 26 ]. The responses were categorized into poor (0–5), reasonable (6–7), good (8–9) and excellent (10). The good and excellent categories were merged and considered as excellent/good work ability. 2.2.4. Job Support and Job Control Job support (5 items) was assessed through questions on horizontal (colleagues) and vertical (supervisors) support, and each item was measured on a scale of “0 (low support) to 10 (high support)” (Cronbach’s α =0.78). The overall score 8–50 was dichotomized into “high” and “low” using the median value (36.0). Job control (4 items) was assessed with questions related to the respondent’s possibility to learn new knowledge and skills (“0”, low—“10”, high), possibility to influence work and working conditions (“0”, never—“3”, usually), experience of doing important and significant work (“0”, never—“5” daily) and having sufficient education to complete the job (“0”, low—“10”, high) (Cronbach’s α =0.73). The overall score 0–27 was dichotomized into “high” and “low” using the median value (17.0) (adapted from von Bonsdorffet al., 2012) [27]. 2.2.5. Other Covariates Demographic information was collected at baseline. The mean age of participants was 58.4 ± 3.4 and 60% were men. Two occupational categories were used: whiteand blue-collar. Working time was assessed as working hours per week. The presence of any physician-diagnosed disease was measured with a yes/no response. Perceived health was assessed using a single item “how do you rate your current health compared to life’s best?” on a scale of “0–10”. Responses were categorized as good (9–10), moderate (7–8) and poor/fair (0–6). Work stress was assessed using a single item “how do you rate the Int. J. Environ. Res. Public Health 2019,16, 2500 4 of 13 level of your work-related stress?” on a scale of “0–10”. Responses were categorized as low (0–6), moderate (7–8) and high (9–10). 2.3. Statistical Analysis Mixture modeling (MM) was used to identify the developmental pathways of work life satisfaction (WLS). Latent class analysis (LCA) was used with continuous latent class indicators and user specified starting values based on the continuous responses of WLS at four lifetime points. LCA is a method that identifies within the data the multiple latent classes with a similar development over time [ 28 ]. The MM was fitted with two to four classes and the best-fitted model was selected, based on Bayesian Information Criterion (BIC) and Akaike Information Criterion (AIC), substantive interpretability of classes, parsimony and entropy [ 28 , 29 ]. The fit indices are presented in Table 1. The four-class model was selected as it had a lower BIC and lower AIC value and distinct development patterns of all four classes. The four-class model resulted in latent classes that represent low, decreasing, moderate and high WLS, respectively. Table 1. Fit indices for trajectories of work life satisfaction. Classes BIC AIC Entropy Posterior Probability 2 27,466.58 27,371.44 0.73 0.92/0.93 3 26,528.19 26,382.68 0.73 0.91/0.89/0.86 4 25,934.67 25,738.79 0.75 0.87/0.88/0.92/0.84 BIC, Bayesian Information Criteria; AIC, Akaike Information Criteria. The differences between work ability categories, trajectories of WLS, work and behavior related explanatory factors were examined using χ2 test (p<0.05) and analysis of variance. A generalized linear model was used to calculate the Risk Ratio (RR) and their 95% Confidence Intervals (CIs) for the association between exposures and intention to retire. We observed no interaction between gender, age and exposures associated with the outcome, so models were adjusted for age and gender. The final model was adjusted for age, gender, working hours per week, job support, job control, work stress, perceived health status and occupational class. The respective RR estimates were used to calculate the percentage of excess risk mediated (PERM). The selection of confounders and method of calculation of PERM and proportion of risk mediated was adapted from [12]. We estimated the PERM as follows: PERM =RR (age and gender adjusted)−RR(fully adjusted) [RR (age and gender adjusted)−1]×100. The variables with higher (PERM) values were selected (traditional difference method) [ 30 ] and treated as mediators in the generalized structure equation modeling (GSEM). A variable should be representative of a process in a causal chain between the exposure (work ability and trajectories of WLS) and the intended outcome (ITR) to be considered a mediator, which requires the variable to be correlated with both exposure and outcome [ 31 ]. GSEM was used to calculate the natural direct and natural indirect effects, and based on those effects, the proportion mediated was calculated for the mediators (often called a counterfactual method). In this analysis, both exposures were constructed and used as binary variables (Work ability: Poor +Moderate versus Good +Excellent & WLS: Low + Decreasing versus Moderate +High). In the traditional analysis, the age and gender adjusted model was treated as a crude model. The final model was controlled for mediators in order to calculate the proportion mediated. In the counterfactual analysis, the models were similarly controlled for age and gender and proportion mediated (by allowing mediators in the model) was calculated using natural direct, natural indirect and total effects. MM was executed in Mplus version 7.11 (Muthen & Muthen, 3463 Stoner Ave., Los Angeles, CA, USA) and all other analyses were executed in STATA 14.0 (StataCorp LP, College Station, TX, USA). Int. J. Environ. Res. Public Health 2019,16, 2500 5 of 13 3. Results Four distinct pathways of WLS were identified: high (33%), moderate (35%), decreasing (23%) and low (9%) (Figure 1). WLS was mostly increasing or constant from 15–29 years to 30–39 years for the low, moderate and high trajectory group. However, for the decreasing trajectory group, WLS was already decreased from 15–29 years with a sharp decline after 30–39 years of age. Int. J. Environ. Res. Public Health 2019, 16, x 5 of 14 Four distinct pathways of WLS were identified: high (33%), moderate (35%), decreasing (23%) and low (9%) (Figure 1). WLS was mostly increasing or constant from 15–29 years to 30–39 years for the low, moderate and high trajectory group. However, for the decreasing trajectory group, WLS was already decreased from 15–29 years with a sharp decline after 30–39 years of age. Figure 1. Trajectories of work life satisfaction among the respondents. Participant demographics and other work-related characteristics in relation to work ability and trajectories of WLS are described in Table 2. Approximately 40% of the respondents indicated that they intended to retire early, that is before the official retirement age. Excellent/good work ability was reported by 40% of the respondents, followed by moderate (34%) and poor (26%). The age of the respondents was significantly different among trajectory groups. Perceived health of the respondents was significantly different between work ability categories and WLS trajectories. Similarly, responses on job support and job control were significantly different among work ability categories (55% of the respondents with high job support had excellent work ability) and WLS trajectories (42% of the respondents with high job support had high WLS). Likewise, working hours per week and work stress differed according to the work ability and WLS pathway in which an individual belonged. Respondents with good/excellent work ability and high WLS reported lower work stress compared to those with poor work ability and low WLS. The estimates for the association (Risk Ratio, RR; 95% Confidence Interval, CI; Percentage of excess risk mediated, PERM) between work ability and ITR with simultaneous adjustments for various characteristics of the study population are described in Table 3. Following adjustments for age and gender, participants with moderate work ability (RR 2.07, 95% CI 1.72–2.51) and poor work ability (RR 3.73, 95% CI 3.14–4.42) had an increased likelihood of indicating ITR early compared to the participants with excellent/good work ability. Following adjustment for age, gender, working hours per week, job support, job control, work stress, perceived health status and occupational class, the estimates were attenuated (RR 1.36, 95% CI 1.09–1.70 for moderate; RR 1.79, 95% CI 1.40–2.29 for poor). Among work-related variables, in a step wise adjustment of the age and gender adjusted model, the adjustment for job support (PERM 11.2% for moderate and PERM 15.0% for poor) and job control (8.4% and 9.9%) contributed to the higher attenuation of these associations. The association between trajectories of WLS and ITR are shown in Table 4. Following adjustments for age and gender, participants with moderate WLS had almost similar probability (RR 1.09, 95% CI 0.92–1.29), while those with decreasing (RR 2.26, 95% CI 1.95–2.60) and those with low (RR 1.59, 95% CI 1.30–1.95) had an increased likelihood of indicating ITR early compared to those 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 15-29 30-39 40-49 50-59 WORKING LIFE SATISFACTION SCORE Age interval in years as life-time points High (33%) Moderate (35%) Decreasing (23%) Low (9%) Figure 1. Trajectories of work life satisfaction among the respondents. Participant demographics and other work-related characteristics in relation to work ability and trajectories of WLS are described in Table 2. Approximately 40% of the respondents indicated that they intended to retire early, that is before the official retirement age. Excellent/good work ability was reported by 40% of the respondents, followed by moderate (34%) and poor (26%). The age of the respondents was significantly different among trajectory groups. Perceived health of the respondents was significantly different between work ability categories and WLS trajectories. Similarly, responses on job support and job control were significantly different among work ability categories (55% of the respondents with high job support had excellent work ability) and WLS trajectories (42% of the respondents with high job support had high WLS). Likewise, working hours per week and work stress differed according to the work ability and WLS pathway in which an individual belonged. Respondents with good/excellent work ability and high WLS reported lower work stress compared to those with poor work ability and low WLS. Int. J. Environ. Res. Public Health 2019,16, 2500 6 of 13 Table 2. Cross tabulation of Basic characteristics of study population and exposure variables. Characteristics of the Study Population n=1466 a Work Ability (1466) bSatisfaction in Working Life (n =1413) b,c Good/Excellent (n =590) % Mode-Rate (n =503) % Poor (n =363) % p-Value dHigh (n =466) % Mode-Rate (n =498) % Decreasing (n =325) % Low (n =124) % p-Value d Gender Women 587 42 31 27 0.082 35 38 21 6 0.009 Men 879 39 37 24 32 33 24 11 Age (years) 51–53 327 47 34 19 0.053 31 36 24 9 0.001 54–56 435 40 33 27 32 31 26 11 57–59 397 36 37 27 31 37 25 7 ≥60 293 40 35 25 39 40 13 8 Occupational Class White-Collar 188 63 24 13 <0.001 38 50 6 6 <0.001 Blue-Collar 1264 37 36 27 32 33 26 9 Job Support High 668 55 32 13 <0.001 42 42 9 7 <0.001 Low 786 28 37 35 25 29 35 11 Job Control High 659 54 30 16 <0.001 43 41 11 6 <0.001 Low 797 30 38 32 25 31 33 11 Perceived Health Good 469 82 15 3 <0.001 44 38 10 8 <0.001 Moderate 684 28 55 17 31 40 21 8 Poor 302 4 18 78 19 21 48 12 Working hrs/week 3–35 187 31 28 41 <0.001 27 32 24 16 0.004 36–40 1066 42 36 22 34 36 22 8 >40 129 43 35 22 29 36 28 7 Work stress Low 884 45 32 23 <0.001 37 35 18 10 <0.001 Moderate 432 35 39 26 29 38 27 6 High 141 27 35 38 19 26 44 11 Notes: aColumn total is not equal to N in some variables; brow percentage; cn=1413 due to selection for developmental pathways; dχ2-test. Int. J. Environ. Res. Public Health 2019,16, 2500 7 of 13 The estimates for the association (Risk Ratio, RR; 95% Confidence Interval, CI; Percentage of excess risk mediated, PERM) between work ability and ITR with simultaneous adjustments for various characteristics of the study population are described in Table 3. Following adjustments for age and gender, participants with moderate work ability (RR 2.07, 95% CI 1.72–2.51) and poor work ability (RR 3.73, 95% CI 3.14–4.42) had an increased likelihood of indicating ITR early compared to the participants with excellent/good work ability. Following adjustment for age, gender, working hours per week, job support, job control, work stress, perceived health status and occupational class, the estimates were attenuated (RR 1.36, 95% CI 1.09–1.70 for moderate; RR 1.79, 95% CI 1.40–2.29 for poor). Among work-related variables, in a step wise adjustment of the age and gender adjusted model, the adjustment for job support (PERM 11.2% for moderate and PERM 15.0% for poor) and job control (8.4% and 9.9%) contributed to the higher attenuation of these associations. Table 3. Association between work ability and intention to retire with simultaneous adjustments for different characteristics of the study population. Models Good/Excellent Work Ability Moderate Work Ability PERM Poor Work Ability PERM RR RR 95% CI % RR 95% CI % Adjusted for age +gender 1.0 2.07 1.72–2.51 Reference 3.73 3.14–4.42 Reference +Occupational class 1.0 2.05 1.69–2.48 1.9 3.65 3.07–4.34 2.9 +Perceived Health 1.0 1.58 1.28–1.95 45.8 2.01 1.56–2.60 63.0 +Job control 1.0 1.98 1.63–2.41 8.4 3.46 2.89–4.14 9.9 +Job support 1.0 1.95 1.61–2.37 11.2 3.32 2.77–3.97 15.0 +Working hours/week 1.0 2.02 1.66–2.45 4.7 3.62 3.05–4.30 4.0 +Work stress 1.0 2.03 1.67–2.45 3.7 3.59 3.02–4.27 5.1 +All above factors 1.0 1.36 1.09–1.70 66.4 1.79 1.40–2.29 71.1 Notes: RR, Relative Risk; CI, Confidence Interval; All separate analyses are adjusted with age and gender; PERM, Percentage of excess risk mediated (age and gender adjusted estimate used as referent group for calculation); WLS, satisfaction in working life. The association between trajectories of WLS and ITR are shown in Table 4. Following adjustments for age and gender, participants with moderate WLS had almost similar probability (RR 1.09, 95% CI 0.92–1.29), while those with decreasing (RR 2.26, 95% CI 1.95–2.60) and those with low (RR 1.59, 95% CI 1.30–1.95) had an increased likelihood of indicating ITR early compared to those with a high level of WLS. Following adjustment for age, gender, working hours per week, job support, job control, work stress, perceived health status and occupational class, only those with decreasing WLS had significantly higher probability (RR 1.29, 95% CI 1.13–1.46) compared to those with high levels of WLS. The large proportion of the respondents falling under decreasing WLS had poor perceived health, low job support, low job control, high work stress and were blue collar workers. In addition, decreasing WLS represented almost 50% of respondents with intentions to retire early. Therefore, the decreasing WLS group had a higher risk of early retirement. Among work-related variables, in a step wise adjustment of age and gender adjusted model, the adjustment for job support (PERM 34% for decreasing WLS and PERM 36.0% for Low WLS) and job control (27% and 32%) contributed to the higher attenuation of these associations. The largest attenuation of the associations (PERM) presented in Tables 3and 4in stepwise adjustments were due to job support and job control. As a result, these were then checked as mediators in the association between exposures (work ability and WLS) and ITR. In addition, both job support and job control were associated with both exposures and outcome, and therefore considered potential mediators. RR and 95% CI for the association between exposures (work ability and trajectories of WLS) and ITR with job support as mediator and proportions mediated is presented in Table 5. The risk of ITR early was decreased by 14% among those with poor work ability (poor +moderate versus good +excellent) and by 20.6% among those with low WLS (low +decreasing versus high +moderate) when controlled for job support in the model without exposure mediator interaction. Job control as mediator and proportions mediated is presented in Table 6. The risk of ITR early was decreased by Int. J. Environ. Res. Public Health 2019,16, 2500 8 of 13 9.3% among those with poor work ability and by 14.7% among those with low WLS when job control was controlled for. The exposure mediator interaction did not describe the association. Table 4. Association between satisfaction in working life (WLS) and intention to retire with simultaneous adjustments for different characteristics of the study population. Models High WLS Moderate WLS Low WLS PERM Decreasing WLS PERM RR RR 95% CI RR 95% CI % RR 95% CI % Adjusted for age +gender 1.0 1.09 0.92–1.29 1.59 1.30–1.95 Reference 2.26 1.95–2.60 Reference +Occupational class 1.0 1.07 0.89–1.29 1.48 1.17–1.87 18.6 2.10 1.80–2.46 12.7 +Perceived Health 1.0 1.05 0.89–1.23 1.14 0.93–1.39 76.3 1.35 1.17–1.55 72.2 +Job control 1.0 1.03 0.86–1.24 1.40 1.11–1.77 32.2 1.92 1.62–2.28 27.0 +Job support 1.0 1.04 0.86–1.24 1.38 1.09–1.73 35.6 1.83 1.55–2.16 33.9 +Working hours/week 1.0 1.05 0.88–1.27 1.46 1.15–1.86 22.0 2.11 1.80–2.48 11.9 +Work stress 1.0 1.05 0.88–1.26 1.49 1.18–1.88 16.9 2.04 1.73–2.42 17.4 +All above factors 1.0 1.07 0.92–1.26 1.07 0.91–1.26 88.0 1.29 1.13–1.46 77.0 Notes: RR, Relative Risk; CI, Confidence Interval; All separate analyses are adjusted with age and gender; PERM, Percentage of excess risk mediated (age and gender adjusted estimate used as referent group for calculation). Table 5. Risk Ratio (RR) and 95% CI on the association between exposures (work ability and satisfaction in work life (WLS)) and outcome (intention to retire) with Job support as the mediator. Method of Analysis RR 95% CI Proportion Mediated (%) Traditional analysis for work ability Poor +Moderate versus Good +Excellent work ability a2.78 2.34–3.30 Reference Poor +Moderate versus Good +Excellent work ability b2.50 2.10–2.98 15.7 Counterfactual analysis a Good +Excellent versus Poor +Moderate work ability (effect), without exposure mediator interaction Direct effect 1.37 1.31–1.44 Indirect effect 1.04 1.03–1.06 Total effect 1.43 1.36–1.50 14 Good +Excellent versus Poor +Moderate work ability (effect), with exposure mediator interaction Direct effect 1.30 1.21–1.39 Indirect effect 1.02 1.00–1.05 Total effect 1.33 1.23–1.44 9 Traditional analysis for WLS Low +Decreasing versus High +Moderate WLS a1.92 1.71–2.16 Reference Low +Decreasing versus High +Moderate WLS b1.68 1.48–1.90 26.1 Counterfactual analysis a High +Moderate versus Low +Decreasing WLS (effect), without exposure mediator interaction Direct effect 1.27 1.11–1.23 Indirect effect 1.06 1.03–1.08 Total effect 1.34 1.27–1.41 20.6 High +Moderate versus Low +Decreasing WLS (effect), with exposure mediator interaction Direct effect 1.19 1.08–1.31 Indirect effect 1.05 1.02–1.07 Total effect 1.24 1.12–1.38 21 Notes: RR, Risk Ratio; CI, Confidence Interval; a Adjusted for age and gender; b Adjusted for age, gender and job support. Int. J. Environ. Res. Public Health 2019,16, 2500 9 of 13 Table 6. Risk Ratio (RR) and 95% CI on the association between exposures (work ability and satisfaction in work life (WLS)) and outcome (intention to retire) with Job Control as the mediator. Method of Analysis RR 95% CI Proportion Mediated (%) Traditional analysis for work ability Poor +Moderate versus Good +Excellent work ability a2.78 2.34–3.30 Reference Poor +Moderate versus Good +Excellent work ability c2.58 2.16–3.08 11.2 Counterfactual analysis a Good +Excellent versus Poor +Moderate work ability (effect), without exposure mediator interaction Direct effect 1.39 1.32–1.46 Indirect effect 1.03 1.01–1.04 Total effect 1.43 1.36–1.50 9.3 Good +Excellent versus Poor +Moderate work ability (effect), with exposure mediator interaction Direct effect 1.36 1.27–1.46 Indirect effect 1.02 1.00–1.04 Total effect 1.40 1.29–1.51 10 Traditional analysis for WLS Low +Decreasing versus High +Moderate WLS a1.92 1.71–2.16 Reference Low +Decreasing versus High +Moderate WLS c1.74 1.53–1.98 19.6 Counterfactual analysis a High +Moderate versus Low +Decreasing WLS (effect), without exposure mediator interaction Direct effect 1.29 1.22–1.37 Indirect effect 1.04 1.02–1.06 Total effect 1.34 1.27–1.42 14.7 High +Moderate versus Low +Decreasing WLS (effect), with exposure mediator interaction Direct effect 1.29 1.17–1.43 Indirect effect 1.04 1.01–1.06 Total effect 1.34 1.21–1.49 14.7 Notes: RR, Risk Ratio; CI, Confidence Interval; a Adjusted for age and gender; c Adjusted for age, gender and job control. 4. Discussion The current study aimed to investigate the role of work ability and trajectories of WLS in predicting ITR amongst employees aged over 50 years of age. Four distinct pathways of WLS were identified: high, moderate, decreasing and low. Most employees were in the high and moderate pathways of WLS and reported excellent/good work ability. However, in relation to the key influences on ITR early, those with poor work ability and decreasing WLS were more likely to indicate an ITR before the pensionable age. However, high levels of support and control at the workplace were found to ameliorate the risk of early retirement. The comparison with the existing literature suggests that our findings are plausible. In line with previous research, those with lower job satisfaction and poor work ability were more likely to indicate an intention to retire early [ 7 , 11 – 13 , 32 ]. More specifically, Oakman and Wells (2016) found that the relationship between job satisfaction and ITR early was mediated by work ability, offering organizations an opportunity to design work to enable those with lower work ability to remain at work. An 11-year longitudinal analysis of Finnish employees reported work ability as a stable predictor of ITR early (Von Bonsdorffet al., 2010) [ 9 ]. In addition, our study is in line with previous studies in terms of a positive association between high WLS and delayed ITR [ 5 , 6 , 9 ]. There was a direct transition to early retirement among the people with declining work ability in the U.S. [ 13 ]. However, the role of other work-related conditions were not reported in the study. The important role of working conditions in reducing the likelihood that employees will retire early was identified in the current study. They are of particular significance and offer insights into potential mechanisms for developing strategies to encourage retention. It is not surprising that job control was also relevant in its association with intention to retire. Allowing individuals to plan their work may enable them to manage some level of incapacity or lower work ability through structuring of their work tasks in a way that they are able to complete. Those with high psychological demands were