The Japanese version of the occupational future time perspective scale: A validation study

Abstract

Objective

This study aimed to develop and validate a Japanese version of the Occupational Future Time Perspective scale (OFTP-J) and assess its structural validity, construct validity, internal consistency, and test–retest reliability among Japanese workers.

Methods

The online survey was conducted with 2046 participants who met the eligibility criteria. The Japanese version of the OFTP scale was developed through translation and back-translation processes. Confirmatory factor analysis was performed to evaluate the structural validity. Pearson's correlations were computed to assess construct validity, and Cronbach's alpha coefficients were calculated to determine internal consistency. Test–retest reliability was examined using Cohen's weighted kappa coefficients and intraclass correlation coefficients.

Results

The confirmatory factor analysis supported an 8-item model with three factors (i.e., focus on opportunities, perceived remaining time, and focus on limitations) for the Japanese version of the OFTP scale. The scale demonstrated high internal consistency, with Cronbach's alpha coefficients ranging from 0.81 to 0.92. Construct validity was supported by significant correlations between the OFTP scale and its subscales, possible antecedents (age, self-rated health, and job control), and possible outcomes (learning goal orientation, job crafting, and work engagement). Test–retest reliability was confirmed with moderate agreement.

Conclusions

The OFTP-J was found to be reliable and valid. It can be used to measure OFTP among Japanese workers and facilitate comparative research with the original English version. The OFTP-J provides valuable insights into the learning motivation and work engagement of the aging workforce.

INTRODUCTION

In developed countries, the working-age population is declining due to falling birth rates.¹ As a result, it has become necessary for workers to continue working beyond the traditional retirement age in order to secure the labor force and sustain social systems. In Japan, the decline in the working-age population is occurring at a faster pace compared to other developed countries.² To address this situation, a bill to amend the Law for Securing Employment of the Elderly was passed in March 2020, which mandates companies to extend the period for securing employment from 65 to 70 years.³

The recent rapid development of artificial intelligence and other technological innovations requires workers to adapt to changes in the work environment. In order for workers to maintain their health and productivity in such an environment, it is crucial to enhance both learning motivation and work engagement regardless of age. Numerous studies have reported an increase in work engagement with age.^4,5 However, this increase is primarily influenced by an improvement in emotional regulation,^6,7 while learning motivation tends to decline with age.^8,9

Based on the conservation of resources theory, individuals strive to acquire and accumulate resources to cope with stressful conditions.¹⁰ Another relevant theory is the socioemotional selectivity theory (SST), which is one of the main theories in lifespan development psychology. It suggests that as people become more aware of the limited time they have, their goals shift from gaining knowledge, which is instrumental for the future, to placing a greater emphasis on positive emotional states and meaning.¹¹

Occupational future time perspective (OFTP) refers to workers' perceptions of the remaining time, opportunities, and limitations in their careers.¹² OFTP, which adapts Carstensen and Lang's general future time perspective (general FTP)¹³ consisting of 10 items to the work context,¹⁵ comprises three dimensions: focus on opportunities (FOO), perceived remaining time (PRT), and focus on limitations (FOL). FOO involves perceiving goals, opportunities, and possibilities that are still available in the work setting. PRT pertains to the time individuals believe they have left in their work or employment before retiring. FOL focuses on the restrictions and constraints related to one's work.

OFTP has been found to be negatively associated with age, but there are significant individual differences due to the influence of factors such as personality and health conditions.^14,16 Health is one of the personal resources that may contribute to perceptions of future time and opportunities by helping individuals work better and for longer.¹⁷ Additionally, contextual factors such as job characteristics, for example, job control and job complexity, and personnel policies have been identified as antecedents of OFTP.^14,16 They may help individuals gain additional resources in terms of FOO and PRT.^12,17

It was reported that OFTP was positively associated with motivational outcomes like learning motivation,^18,19 and behavioral and attitudinal outcomes such as job crafting,^20,21 as well as occupational well-being outcomes such as work engagement.^16,22,23 Workers with high levels of FOO and PRT tend to think positively about their professional futures and perceive new goals in their upcoming work roles.¹² According to SST, life entails two main types of social goals: future-oriented goals, which are aimed at resource acquisition, and emotionally meaningful goals.²⁴ FTP is crucial in selecting and pursuing these goals.²⁵ Specifically, when time is perceived as open-ended, individuals prioritize future-oriented goals related to learning motivation.²⁴ Job crafting refers to the proactive adjustments individuals make to their job roles, aiming to better align them with personal preferences and goals and to enhance feelings of purpose and work significance.²⁶ Drawing from SST, workers with an open-ended FTP, who prioritize knowledge acquisition, are more likely to craft their jobs in ways that offer developmental opportunities.²⁷ For effective work engagement, goals should be achievable.²⁸ Individuals with a high OFTP tend to formulate such achievable goals and plans, fostering better work engagement.²³ Furthermore, work engagement can be enhanced by alterations in job crafting behaviors.²⁰ Subscales of OFTP are also based on SST, which may have similar relationships to their respective outcomes. Thus, with the aging of workers, if organizational efforts can enhance their OFTP, workers may be able to sustain their work engagement and learning motivation, which are important indicators not only for human resource management but also for health management in a future society where workers are aging.

To date, studies utilizing the OFTP scale have primarily been conducted in English, German, and Dutch-speaking countries,¹⁶ with a Spanish version also available.²⁹ However, there is currently no validated Japanese version. In countries with shrinking working-age populations, the duration of employment for older workers is expected to be further extended in the near future. Given these circumstances, societies and organizations need to understand the factors that effectively contribute to the motivation and engagement of the aging workforce, enabling them to adapt to rapid changes. While numerous studies on the association between age and OFTP with various work-related factors have been conducted in Europe, it is also essential to conduct research on OFTP in Japan, where the workforce is rapidly aging.

The purpose of this study was to develop a validated Japanese version of the OFTP scale. Specifically, we translated the original English version of the OFTP scale into Japanese and assessed its structural and construct validity, as well as its internal consistency and test–retest reliability with Japanese workers.

METHODS Participants

The online survey was conducted by Cross Marketing Inc., which has 5.0 million registrants from January 23 to January 26, 2023. Out of the registrants, 41 235 individuals received an invitation via email to participate in the survey. A total of 5882 registrants completed the screening questions to determine eligibility for the survey. Due to budget constraints, the target was to obtain 2000 responses that met the survey's criteria, and participants were selected on a first-come, first-served basis. Originally, the OFTP was developed as a tool specifically for gauging the characteristics of older workers.¹⁵ However, most previous research on OFTP was conducted with workers across the entire working lifespan.^{12,17,19,20,21,23,29} Using a broad age range has also been recommended by methodologists in the field of work and aging.³⁰ Therefore, the criteria for this survey included employed individuals aged between 20 and 69 years. All collected responses were subsequently included in the analysis.

A follow-up survey was conducted to assess test–retest reliability. Although there were no data on changes in OFTP within individuals, this indicator was expected to exhibit some stability. However, potential challenges arose: A too-short interval might have allowed the memory of responses from the baseline to influence answers, while a too-long interval could have been affected by events between the surveys. Consequently, we set the interval between the surveys at 2 weeks. The target population for the follow-up survey was 600 respondents, selected on a first-come, first-served basis from the baseline survey participants.

Measures OFTP scale

The correspondence between each subscale and the question in the Original OFTP scale was as follows: FOO (four items): “Many opportunities await me in my occupational future, “I expect that I will set many new goals in my occupational future,” “My occupational future is filled with possibilities,” and “I could do anything I want in my occupational future,” PRT (four items): “There are only limited possibilities in my occupational future,” “There is plenty of time left in my occupational life to make new plans,” “There are only limited possibilities in my occupational future,” “There are only limited possibilities in my occupational future,” and FOL (two items): “There is plenty of time left in my occupational life to make new plans” and “As I get older, I begin to experience time in my occupational future as limited.”

A Japanese translation of the Original OFTP scale was created following the guidelines of the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) task force.³¹ Initially, four researchers (KM, KO, KH, and NI) independently translated the Original OFTP scale¹⁵ into Japanese, and a draft Japanese version was developed through discussions among the researchers. Bilingual Japanese-English experts, who were unfamiliar with the original scale, were then asked to back-translate the Japanese version into English. The back-translated English version was reviewed by the original author (HZ), confirming that the back-translated items were equivalent to the original items, except for the translation of “my occupational future” to “my career.” Based on the author's recommendation, the word “career” was modified to “focus on the future” to exclude references to the past. The four researchers involved in the translation process compared the Original OFTP scale with the back-translated version. Since the Japanese draft version clearly expressed the relevant future-oriented meaning, no revisions were made. Subsequently, nine workers from various occupations and age groups were asked to provide feedback on the questionnaire's comprehensibility and any difficulties encountered while answering. Minor comments were received, mainly related to the use of adjectival phrases and endings. The researchers reviewed the comments and made adjustments that did not affect the meaning of the translated words in English. Thus, the Japanese OFTP scale (OFTP-J) for the test was finalized (Table S1).

The OFTP-J for the test consisted of 10 items. Respondents were asked to rate each item on a 5-point scale, where 1 = “strongly disagree,” 2 = “disagree,” 3=“neither agree nor disagree,” 4 = “agree,” and 5 = “strongly agree.” For the final adopted model, a mean score was calculated for each factor following the previous studies.^15,29 The OFTP value was the mean score for all items after subtracting the value from 6 for reverse-scored items.

Relevant variables

In their qualitative systematic review of general FTP and OFTP, Henry et al. classified the relevant factors into two antecedent categories (individual antecedents and contextual antecedents) and three outcome categories (occupational well-being outcomes, motivational outcomes, and behavioral and attitudinal outcomes).¹⁴ In this study, in addition to chronological age (categorized as an individual antecedent), one indicator from each of the five categories was selected and measured based on the availability of validated Japanese scales and the study's context in Japan.

Possible antecedents

The individual antecedent selected was self-rated health, and the contextual antecedent was job control. Respondents were asked to rate their current health condition on a 6-point scale ranging from 1 = “very good” to 6 = “very bad.” To facilitate comprehension, the scores were reversed for analysis purposes. Job control was assessed using three items from the Brief Job Stress Questionnaire,³² which is primarily utilized in the stress check system implemented by the Industrial Safety and Health Law in Japan. The three items were: “I can work at my own pace,” “I can decide the order and way of work by myself,” and “I can reflect my opinion on the work policy in the workplace.” Respondents indicated their agreement on a 4-point scale ranging from 1 = disagree to 4 = agree, and the mean score was calculated. The Cronbach's alpha coefficient for job control in this sample was 0.87.

Possible outcomes

The motivational outcome selected was learning goal orientation, the behavioral and attitudinal outcome was job crafting, and the occupational well-being outcome was work engagement. Learning goal orientation was assessed using the Japanese translation of the goal orientation scale by Hirst et al.^33,34 The scale consisted of six items, and respondents indicated their agreement on a 5-point scale ranging from 1 = “strongly disagree” to 5 = “strongly agree.” The mean score was used as the indicator. The Cronbach's alpha coefficient for learning goal orientation in this sample was 0.92. Job crafting was measured using a scale comprising 21 items. Respondents indicated the frequency of each behavior on a 5-point scale ranging from 1 = “none at all” to 5 = “very often,” and the mean score was calculated.³⁵ The Cronbach's alpha coefficient for job crafting in this sample was 0.92. Work engagement was measured using the 9-item Japanese version of the Utrecht Work Engagement Scale (UWES-9).³⁶ Respondents indicated their agreement on a 7-point scale ranging from 0 = “I never feel it at all” to 6 = “I feel it all the time,” and the mean score was calculated. The Cronbach's alpha coefficient for work engagement in this sample was 0.96.

Demographic characteristics

Participant characteristics were collected in the first survey. In addition to age, respondents were asked to provide information on gender (male, female), annual household income (<3.00 million Japanese yen [JPY], 3.00–4.99 million JPY, 5.00–9.99 million JPY, and 10.00 million JPY or greater), and final education (junior high or high school, vocational school or college, and university or graduate school). Job category was determined based on the Japan Standard Industrial Classification (December 1997 version) and included the following categories: professional and technical; administrative; clerical; sales; service; security; agriculture, forestry, and fishing; transportation and communication; production process and labor work; and others.

Statistical analysis

The original OFTP scale, developed by applying the general FTP with a 10-item, 3-factor structure,¹² was used as the basis. In an exploratory factor analysis conducted by Zacher,¹⁵ a model consisting of three factors was employed: FOO with three items, PRT with three items, and FOL with two items. Therefore, in this study, confirmatory factor analysis was conducted on the OFTP-J using two candidate models: a 10-item, 3-factor structure and an 8-item, 3-factor structure.¹⁵ Model fit was evaluated using the χ² goodness-of-fit statistic, root mean square error of approximation (RMSEA), standardized root mean square residual (SRMR), comparative fit index (CFI), and Tucker–Lewis index (TLI). Acceptable model fit criteria were defined as RMSEA and SRMR <0.08, and CFI and TLI > 0.90.³⁷ Akaike's Information Criterion (AIC) was also calculated to compare the two models. In addition, an exploratory factor analysis was conducted with the 10 items of OFTP-J for confirmation.

To assess construct validity, Pearson's correlations were computed between the OFTP scale (including its subscales), possible antecedents (age, self-rated health, and job control), and possible outcomes (learning goal orientation, and job crafting, and work engagement).

We tested the known-group validity using the Kruskal–Wallis test to compare the mean ranks of the OFTP and its subscales across different age groups, as age is a major factor influencing OFTP.

Internal consistency reliability was evaluated using Cronbach's alpha coefficients for the OFTP scale and its subscales. To evaluate test–retest reliability, we first conducted the Kolmogorov–Smirnov test to see if the OFTP scale, the subscales, and the items followed a normal distribution. Then, since it could not be confirmed normal distribution, Cohen's weighted kappa coefficient with linear weight was calculated, and Landis and Koch criteria were used for the evaluation: poor: <0, weak: 0–0.20, probable: 0.21–0.40, moderate: 0.41–0.60, substantial: 0.61–0.80, and almost perfect: 0.81–1.00.³⁸ In addition, as parametric statistics for test–retest reliability, intraclass correlation coefficient (ICC) and standard error of measurement (SEM) were also calculated for reference.

Statistical significance was set at P < 0.05 (two-tailed). All statistical analyses were performed using IBM SPSS Amos Version 27.0 and Stata Statistical Software Release 16.

Ethical considerations

The study was approved by the Ethics Committee of Medical Research, University of Occupational and Environmental Health, Japan (R4-065).

RESULTS Participant characteristics

Both the baseline and follow-up surveys received a higher number of responses than the target numbers of 2000 and 600, respectively. Table 1 presents the characteristics of the participants in the baseline and follow-up surveys. In the baseline survey, 55.2% of the participants were male, 52.6% had a college degree or higher, and the most common occupations were clerical, professional and technical, and service occupations, in that order. No significant differences were found between the baseline and follow-up surveys in terms of gender, age, household income, final education, or occupation.

TABLE 1 Demographics of participants at first survey and second survey.

[Table omitted. See PDF]

Structural validity

Confirmatory factor analysis was conducted for the 10-item and 8-item models of the OFTP-J, based on the 3-factor structure of the original OFTP scale. The 8-item model met all the model-fit criteria and demonstrated better goodness of fit compared to the 10-item model (Table 2). Consequently, the 8-item model comprising three subscales (FOO, PRT, and FOL) was selected as the OFTP-J. Table 3 shows the correspondence of each question item to the OFTP subscales and the factor loadings. The result of the exploratory factor analysis with 10 items of OFTP-J indicated that the original three factors were not extracted, and furthermore, the constituent items of PRT were not consolidated into a singular factor but rather distributed across three factors.

TABLE 2 The model fit in the confirmatory factor analysis for 10-items and 8-item model.

	χ 2	df	P	Δχ2	Δdf	P(Δχ2)	RMSEA (90% CI)	SRMR	CFI	TLI	AIC
10-item model	478.1	32	<.001				0.083 (0.076–0.089)	0.049	0.968	0.956	523.9
8-item model	104.4	17	<.001	373.7	15	<.001	0.050 (0.041–0.060)	0.013	0.992	0.988	142.4

Abbreviations: AIC, Akaike's Information Criterion; CRI, comparative fit index; RMSEA, root mean square error of approximation; SRMR, standardized root mean square residual; TLI, Tucker–Lewis index.

TABLE 3 Factor loadings in the confirmatory factor analysis for an 8-item model.

Items		Factor loadings
Focus on opportunities
FOO #1	Many opportunities await me in my occupational future	0.87
FOO #2	I expect that I will set many new goals in my occupational future	0.89
FOO #3	My occupational future is filled with possibilities	0.90
Perceived remaining time
PRT #1	There is plenty of time left in my occupational life to make new plans	0.78
PRT #2	Most of my occupational life lies ahead of me	0.87
PRT #3	My occupational future seems infinite to me	0.87
Focus on limitations
FOL #1	I have the sense that my occupational time is running out	0.84
FOL #2	As I get older, I begin to experience time in my occupational future as limited	0.80

Abbreviations: FOO, Focus on opportunities; FOL, Focus on limitations; PRT, Perceived remaining time.

Construct validity

Table 4 displays the correlations among all study variables, including OFTP-J and the three subscales, as well as possible antecedents (age, self-rated health, and job control) and possible outcomes (learning goal orientation, job crafting, and work engagement). Strong interrelationships were observed between FOO and PRT (r = 0.80), while moderate interrelationships were observed between FOL and other subscales. Age exhibited weak to moderate negative correlations with OFTP-J, FOO, and PRT, and moderate positive correlations with FOL. FOO and PRT showed weak to moderate positive correlations, whereas FOL exhibited negative correlations with other possible antecedents and outcomes.

TABLE 4 Means, standard deviations, and intercorrelations of variables.

		Mean	SD	1	2	3	4	5	6	7	8	9
Occupational future time perspectives
1	Occupational Future time perspective (1–5)	2.63	0.80
2	Focus on opportunities (1–5)	2.65	0.94	0.89**
3	Perceived remaining time (1–5)	2.62	0.94	0.93**	0.80**
4	Focus on limitations (1–5)	3.41	0.97	−0.66**	−0.36**	−0.46**
Possible antecedents
5	Age	46.58	13.64	−0.34**	−0.21**	−0.33**	0.33**
6	Self-rated health (1–6)	4.32	1.00	0.32**	0.32**	0.29**	−0.17**	−0.06*
7	Job control (1–4)	2.71	0.74	0.22**	0.24**	0.22**	−0.07*	0.09**	0.22**
Possible outcomes
8	Learning goal orientation (1–5)	2.79	0.90	0.50**	0.53**	0.50**	−0.16**	−0.03	0.19**	0.23**
9	Job crafting (1–5)	2.39	0.68	0.45**	0.46**	0.46**	−0.16**	−0.18**	0.21**	0.26**	0.57**
10	Work engagement (0–6)	3.51	1.40	0.38**	0.45**	0.37**	−0.05*	0.19**	0.28**	0.33**	0.55**	0.44**

^*P < .05;

^**P < .01.

Known-group validity

Table 5 illustrates the significant differences in the mean ranks of OFPT and its three subscales across different age groups, as analyzed by the Kruskal–Wallis test. A trend was observed where higher age groups had lower mean ranks for OFPT. A similar trend was evident for the three subscales.

TABLE 5 Comparison of the mean ranks of the occupational future time perspectives and its subscales by age groups (Kruskal–Wallis test).

[Table omitted. See PDF]

Internal consistency and test–retest reliability

Table 6 shows Cronbach's alpha coefficient, Cohen's weighted kappa coefficient, ICC, and SEM of OFTP, the subscales, and the items. The Cronbach's alpha coefficients for OFTP-J, FOO, and PRT demonstrated high internal consistency. Regarding test–retest reliability over a 2-week interval, Cohen's weighted kappa coefficients indicated moderate reliability.

TABLE 6 Means, standard deviations, minimum, maximum, Cronbach's alpha coefficients, Cohen's weighted κ coefficients intraclass correlation coefficients, and standard error of measurement for the occupational future time perspective, its subscales, and items.

	Mean	SD	Min	Max	Cronbach's alpha	Cohen's weighted κ (95% CI)	ICC (95% CI)	SEM (95% CI)
Occupational future time perspective	2.63	0.80	1	5	0.90	0.59 (0.56–0.63)	0.79 (0.76–0.82)	0.47 (0.44–0.50)
Focus on opportunities (FOO)	2.65	0.94	1	5	0.92	0.55 (0.50–0.59)	0.71 (0.67–0.75)	0.63 (0.59–0.67)
FOO#1	2.65	1.00	1	5	–	0.50 (0.45–0.56)	0.61 (0.56–0.66)	0.77 (0.72–0.82)
FOO#2	2.68	1.01	1	5	–	0.52 (0.47–0.57)	0.66 (0.62–0.71)	0.73 (0.68–0.77)
FOO#3	2.62	1.02	1	5	–	0.52 (0.47–0.57)	0.63 (0.58–0.68)	0.77 (0.72–0.82)
Perceived remaining time (PRT)	2.62	0.94	1	5	0.88	0.53 (0.49–0.57)	0.71 (0.67–0.75)	0.63 (0.59–0.68)
PRT#1	2.73	1.02	1	5	–	0.45 (0.39–0.50)	0.54 (0.48–0.60)	0.87 (0.81–0.92)
PRT#2	2.66	1.10	1	5	–	0.55 (0.50–0.60)	0.66 (0.61–0.70)	0.78 (0.73–0.84)
PRT#3	2.48	1.05	1	5	–	0.49 (0.44–0.55)	0.60 (0.55–0.65)	0.81 (0.76–0.86)
Focus on limitation (FOL)	3.41	0.97	1	5	0.81	0.43 (0.38–0.48)	0.55 (0.50–0.60)	0.81 (0.76–0.86)
FOL#1	3.33	1.08	1	5	–	0.41 (0.35–0.46)	0.47 (0.41–0.53)	0.98 (0.92–1.04)
FOL#2	3.50	1.04	1	5	–	0.41 (0.36–0.47)	0.51 (0.45–0.56)	0.90 (0.85–0.96)

Note: Mean, SD, min, max, and Cronbach's alpha were calculated using all responses in the baseline survey.

Abbreviations: CI, Confidence interval; ICC, intraclass correlation coefficients, SEM, standard error of measurement.

DISCUSSION Reliability and validity

In this study, we successfully translated the Original OFTP scale from English to Japanese and confirmed its validity and reliability. Confirmatory factor analysis supported an 8-item model with three factors, which was adopted as the OFTP-J. The subscales of the OFTP-J were named consistently with the original OFTP scale: “focus on opportunities (FOO)” with three items, “perceived remaining time (PRT)” with three items, and “focus on limitations (FOL)” with two items. This model aligns with the model proposed by Zacher.¹⁵

Regarding reliability, both the Japanese version of the OFTP and its subscales demonstrated high internal consistency, with Cronbach's alpha coefficients ranging from 0.92 to 0.81. Test–retest reliability was confirmed with a moderate agreement, as indicated by Cohen's weighted kappa coefficients and ICC.

Henry et al. conducted a systematic review of antecedents and outcomes of the general FTP in the work context and OFTP.¹⁵ They categorized antecedents into individual and contextual factors, and outcomes into occupational well-being, motivation, and behavioral/attitudinal domains. In this study, we selected one factor from each category and examined their correlations with the OFTP-J and its subscales (FOO, PRT, and FOL). While the relationship between FOO and PRT among the subscales has been extensively studied, FOL has been limited. Therefore, regarding FOL, no comparisons with previous studies were discussed. The observed correlations were in line with previous research, confirming the construct validity of the OFTP-J.

Among the possible antecedents, previous studies have consistently found a negative correlation between OFTP and age, although the strength of the correlation varied across studies.¹⁶ In this study, FOO exhibited a weak negative correlation (r = −0.21) with age, while PRT showed a moderate negative correlation (r = −0.32). This is consistent with previous findings suggesting that FOO has a weaker correlation with age compared to PRT.^12,22,39 The varying strength of correlations across studies may be attributed to differences in sample characteristics. Additionally, there have been studies investigating the relationship between self-rated health as an individual antecedent and OFTP, FOO, and PRT. A meta-analysis by Rudolph et al. found a positive relationship between self-rated health and these variables.¹⁶ In our study, self-rated health, assessed by a single question, exhibited weak positive correlations (r = 0.32, r = 0.32, and r = 0.29) with OFTP, FOO, and PRT, respectively, supporting the findings of the meta-analysis. Job control was employed as a contextual antecedent in this study. While some studies reported a lack of significant association between job control and FOO,^12,20 a meta-analysis by Rudolph et al. indicated a positive and significant relationship between job autonomy and OFTP, as well as FOO.¹⁶ In our study, we found weak positive correlations between job control and FOO (r = 0.22) and PRT (r = 0.24). The differences in findings may be attributed to variations in the target population.

Regarding the possible outcomes, we examined the relationship with learning goal orientation among motivational outcomes. Previous studies have reported a weak positive relationship between OFTP and motivation to learn, as well as a weak positive relationship between constrained PRT and learning goal orientation.^18,19 Additionally, FOO and constrained PRT have been found to correlate with learning self-efficacy and learning value.³⁹ In our study, we found moderate correlations between learning goal orientation and OFTP (r = 0.50), FOO (r = 0.53), and PRT (r = 0.50), which aligns with previous findings. Individuals with a broader OFTP tend to exhibit proactive coping behaviors focused on problem-solving.⁴⁰

Job crafting, corresponding to behavioral and attitudinal outcomes, involves individuals making changes to their work tasks, interpersonal relationships, and cognitive perspectives about work.²⁶ In our study, we observed a moderate correlation between OFTP, FOO, PRT, and job crafting (r = 0.45, 0.46, and 0.46, respectively). Previous studies by Kooij et al.²⁰ and Zacher and Rudolph²¹ have reported positive relationships between job crafting and general FTP, as well as its positive effect on OFTP. Our findings align with these previous studies and indicate a stronger correlation. This relationship may further reinforce the behavior of increasing job resources, which, in turn, can enhance work engagement.⁴¹

Work engagement, a widely used indicator of worker well-being,⁴² was chosen as the occupational well-being outcome. Work engagement has been reported to exhibit a positive relationship with age in numerous studies,^4,5 and our study also found a weak positive correlation (r = 0.19). Previous studies have reported a weak positive correlation between FOO and work engagement,^22,23 and a meta-analysis by Rudolph et al. indicated a stronger positive correlation between FOO and work engagement compared to PRT.¹⁶ In our study, we observed moderate positive correlations between OFTP (r = 0.38), FOO (r = 0.45), PRT (r = 0.37), and work engagement, which is consistent with prior research in terms of the stronger correlation with FOO compared to PRT. Therefore, OFTP can serve as a useful indicator for assessing the conditions under which workers can maintain learning motivation and work engagement as they age.

Practical implications

Psychological measures often reveal differences in responses across countries, reflecting cultural variations in attitudes toward employment among workers.⁴³ With the development of the OFTP-J, it is expected to promote research using the OFTP in Japan, where the population is rapidly aging, within the context of Japanese culture and environment. In Japan, the government has implemented health and productivity management initiatives to maintain and enhance the physical and mental well-being of workers, enabling them to extend their working lives.⁴⁴ Although previous studies have examined antecedents of OFTP such as self-rated health and job characteristics, the relationship between OFTP and other factors targeted by health and productivity management, such as lifestyle, and psychosocial work environment, has not been sufficiently explored. Since OFTP is an indicator related to workers' well-being and learning motivation, crucial for successful adaptation to change, it plays a significant role in long-term employment and successful aging at work. Further research is warranted to investigate the relationship between these factors and OFTP, particularly within the context of health and productivity management.

Limitations

Several limitations should be acknowledged in this study. First, the sample was obtained from a single Internet company and may not be representative of the general population of Japanese workers. The overrepresentation of professional and technical workers and those with higher education levels may have influenced the results. Second, the construct validity in this study relied on self-administered indicators derived from the same questionnaire responses. It would be beneficial to examine the relationship between OFTP and more objective measures in future research. Third, a single-item scale was used to measure self-rated health, which may have limitations in terms of validity and sensitivity. Fourth, this study did not assess criterion validity, cross-cultural validity, or responsiveness, which should be examined in future investigations. Fifth, the test–retest reliability, as assessed by Cohen's weighted kappa coefficients, was only moderate. The interval between the baseline and follow-up surveys was 2 weeks, which may have been too long.

CONCLUSIONS

In conclusion, this study demonstrates that the Japanese version of the OFTP (OFTP-J) is reliable and valid, allowing for comparative measurement with the original English version. The availability of the OFTP-J opens up opportunities for its application in Japanese workplaces, particularly in the context of an aging population.

AUTHOR CONTRIBUTIONS

Koji Mori, Kiminori Odagam, and Tomohisa Nagata designed the study; Koji Mori, Kiminori Odagam, Ko Hiraoka, Naoto Ito, and Hannes Zacher participated in the development of the Japanese version of the scale; Koji Mori, Kiminori Odagam, Akiomi Inoue analyzed the data; Koji Mori led the writing of the article, and all other authors were involved in the drafting the article. All authors read and approved the final article.

ACKNOWLEDGMENTS

We thank Dr. Kaoru Ichikawa, Resilie Laboratory Inc., for her professional support in the process of developing the Japanese version scale as a bilingual Japanese-English expert.

FUNDING INFORMATION

This work was financially supported by the University of Occupational and Environmental Health, Japan, and the HASEKO Corporation.

DATA AVAILABILITY STATEMENT

The data that support the findings of this study are available from the corresponding author upon reasonable request.

DISCLOSURE

Approval of the research protocol: The study was approved by the Ethics Committee of Medical Research, University of Occupational and Environmental Health, Japan (reference No. R4-065). Informed Consent: Informed consent was obtained in the form of the website. Registry and the Registration: No. of the study/trial: N/A, Animal Studies: N/A. The authors declare no conflicts of interest associated with this manuscript.