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Developments in Quality of Work-Life Research and Directions for Future Research

Objective of this paper was to observe trends and developments in quality of work-life research throughout the decades. Previous researchers mostly focused on systematic and general literature reviews. In this paper bibliometric analysis and systematic literature review were combined to observe the trends and developments in quality of work-life research. An electronic Scopus database search initially produced of 867 documents on quality of work-life. Further purposive screening reduced the documents to 752 altogether. Furthermore, a detailed literature review of top 10 most cited publications throughout the decades of quality of work-life research was conducted, to explore construct development, antecedents, and outcomes of quality of work-life. Bibliometric analysis revealed that most of the research was produced from United States, and in areas of business, management, and accounting. Literature review revealed that from 1970s to 1980s, the focus of quality of work-life research was mainly on construct development. From 1990s onward, researchers mostly focused on identifying antecedents and outcomes of quality of work-life at organizational and employee level. Findings of this research suggests various employee and organizational level factors which have been neglected by most influential studies of quality of work-life throughout the decades. Future researchers should focus on these factors to motivate government and organizations to incorporate these factors in their system, and to support the quality of work-life research.


Introduction
In general, quality of work-life (QWL) refers to an employee's satisfaction with the working life. It emphasizes the quality of the relationship between the worker and the working environment (Rose et al., 2006). As its conceptualization covers a broad spectrum of factors, researchers operationalized QWL differently in different time periods. From 1960s to 1980s, QWL was limited to desirability of working conditions. Later on, need satisfaction approach emerged during 1980s and 2000s. Currently, researches are using combination of both approaches as per their judgment (Gogoleva et al., 2017). Combination of these approaches yield a broad spectrum of QWL dimensions, such as; employees' feelings toward job content, physical work environment, pay, benefits, promotions, autonomy, teamwork, participation in decision-making, occupational health and safety, job security, communication, colleagues and managers support and work-life balance (Adhikari & Gautam, 2010), and several others. Conclusively, QWL is a combination of all those factors which are critical to attract and retain qualified employees (Mazlan et al., 2018;Mosadeghrad, 2013;Sulaiman et al., 2015).
As QWL is equally important for both employees and organizations, researchers from different fields extensively researched it. Since the origin of QWL research, interest of researchers is continuously shifting. But these trends in QWL research are not fully explored. As the previous studies conducted in this regard were quite limited in their scope. Gogoleva et al. (2017) conducted a detailed bibliometric literature review of 387 publications to explore research perspectives and problems in conceptualization and operationalization of QWL. But his research was limited to only organizational studies. Several other researchers conducted literature reviews but those reviews had their own limitations, in terms of area and time period. There is a need to conduct bibliometric analysis along with literature review to identify the past trends in QWL research. So that research gaps could be identified thoroughly, and further empirical research could be conducted on untouched topics and domains in QWL research.
To address this issue and to overcome this gap, a rigorous bibliometric analysis accompanied with detailed literature review was conducted in this study. The rationale behind combining bibliometric analysis with literature review was to identify: (1) Publication trends throughout the decades of QWL research, (2) Most influential publications throughout the decades of QWL research, (3) Most researched antecedents and outcomes of QWL throughout the decades of QWL research, (4) Development of QWL construct throughout the decades of QWL research, (5) New antecedents and outcomes of QWL contributed by most influential studies throughout the decades of QWL research, (6) Areas of QWL research which require additional research. To meet these objectives, a decade wise bibliometric analysis and literature review was conducted, in order to identify publication trends and main contributions in QWL research throughout the decades of QWL research. Hence, the focus of this research was mainly to observe research trends, contributed dimensions, antecedents, and outcomes of QWL during several decades of QWL research. Directions for future research are suggested based on identified trends and contributions.

Methodology
To fulfill first objective of this research, publication trends were identified through bibliometric analysis of publications throughout the decades of QWL research. For second objective, most influential publications throughout the decades of QWL research were identified through their total citations throughout the years. To achieve third, fourth, fifth, and sixth research objectives, systematic literature review of top 10 most cited publications throughout the decades of QWL research was done. To further facilitate the sixth research objective, keyword analysis was also performed. Bibliometric analysis was deemed best for this research, as it aids in identification of scientific research structure (Ronda-Pupo, 2017), current trends and future research avenues of any field (Li et al., 2017). Systematic literature review further facilitated to identify major contributions in QWL research throughout the decades, in terms of construct conceptualization and development, identification of contributing factors and outcomes, and their implications on both organizational and individual level.
For bibliometric analysis, bibliographic data was extracted through Scopus database as it is one the largest databases of scholarly publications, and covers a vast array of subject areas. Plus it is available for general public without requirement of institutional access to extract bibliographic data from it. After finalizing the database, bibliographic data extraction was performed on 11 August 2021. For this purpose, a detailed search string was constructed to extract bibliographic data from Scopus database, after identifying alternative terms for QWL used in previous studies. Although there are various dimensions of QWL but in this study focus was on those documents which focused on QWL as a whole. Hence, search string was based on various terminologies of QWL including: "quality of work life," "quality of working life," "work life quality," and "working life quality." Search string was constructed in a way that all those documents could be extracted which contain either of these terms in their title. Initially search string was searched through "Article title, Abstract, Keywords," but it filtered even those papers which included the term QWL in their abstract but there focus was nowhere close to QWL. These publications either related the implications of their research with QWL, or just casually mentioned the term in the abstract, with no actual focus on the QWL in their research. Hence, another search was performed with the same search string through the "Article title" only. Following this search strategy, total 867 documents were extracted, starting from the first QWL publication in the Scopus database until now. Covering the QWL research published between 1974 and august 2021. Documents were further filtered based on publication stage, language, and document type. Documents were reduced to 851 after excluding 16 documents in press. Then 84 documents were excluded which were in languages other than English. Lastly, 15 documents were further excluded which were in the form of note, letter, editorial, erratum, and retracted, including documents only in the form of article, conference paper, review, book chapter, and book. After these three filtration parameters, total 752 documents were extracted.
To further analyze the trends and contributions throughout the decades of QWL research, extracted documents were divided in set of several decades starting from beginning of QWL research to present. As the first Scopus indexed publication on QWL was in 1974, so data was further divided into decades of: 1970s, 1980s, 1990s, 2000s, 2010s, and early 2020s. As 2020s is in starting phase hence, documents published only in 2020 and 2021 were analyzed to observe recent advancements. The purpose of forming these small clusters was to better identify trends in QWL research throughout the decades. Important publication trends in these decades were analyzed, including; number of publications in each decade, funded publications, top contributing countries, and top contributing subject areas in QWL research. Then top 10 most cited Scopus indexed publications were shortlisted to conduct a detailed literature review, to analyze construct development, and to identify proposed dimensions, antecedents and outcomes of QWL. A brief summary of search strategy and data filtration process is provided in Figure 1. Bibliometric trend analysis of each decade in QWL research is provided in Appendix Tables 1 to 3
in 1970s. Most of this research was published in business, management, and accounting disciplines (N = 15), and was mainly contributed from United Kingdom (N = 6) and United States (N = 4). Further literature review of top 10 most cited Scopus indexed publications indicated that initial researchers mostly focused on exploring the construct of QWL (Spink, 1975;Taylor, 1978). Along with its several challenges (Westley, 1979), perspectives (Boisvert, 1977;Cherns, 1978;Lippitt, 1978;Newton, 1978), and antecedents (Stokes, 1978;Taylor, 1977). These top cited publications of 1970s are listed in Table 1 along with their citation metrics and ranks. In 1970s, QWL was majorly operationalized through indicators of job satisfaction (Boisvert, 1977;Taylor, 1978). Mostly, researchers operationalized QWL as: opportunities of leaning, importance in decision making, adequate performance feedback, and work control, variety, and recognition (Boisvert, 1977). But, Taylor (1977) challenged this norm and suggested a more detailed scale to measure QWL (Taylor, 1978). Taylor (1978) combined individual categories of QWL, and collective perspectives on QWL in one scale. Individual categories of QWL were composed of; adequate and fair compensation, opportunities for growth, security, safe and healthy working conditions, social integration and constitutionalism in the work organization, work and the total life space, and social relevance of work life. Collective perspectives on QWL were employer and societal QWL (Taylor, 1978).
Until 1970s it was believed that issues of QWL arise due to inequality, insecurity, anomie (Westley, 1979), and alienation (Stokes, 1978). Several indicators of these issues were proposed at that time. Issues of inequality and insecurity can be identified through strikes and sabotage due to job dissatisfaction. Anomie and alienation can be identified through sense of detachment and meaninglessness, absenteeism and increased turnover (Westley, 1979). Researchers of 1970s suggested that inequality issues can be solved through cooperative profit sharing and productivity agreements (Stokes, 1978;Westley, 1979). Insecurity issues can be solved through work self-management, and worker directors and councils. Anomie and alienation issues can be solved through sociotechnically designed work groups, and job enrichment respectively (Westley, 1979). To solve issues of QWL, cooperative union management was highly supported at that time (Drexler & Lawler, 1977;Stokes, 1978;Westley, 1979). One of the most cited proposed union management program was proposed by Drexler and Lawler (1977). In short, focus of 1970s QWL research was mostly on construct exploration and development, and solving issues of QWL.

Focus of Research in 1980s
Bibliometric analysis of Scopus database indicated that QWL research significantly increased in 1980s, as the total publications were 102 in 1980s. Among these 102 publications 7 were funded, indicating budding interest of funding sponsors in QWL. Although highest number of publications were still in business, management, and accounting (N = 39). But, a significant increase in publications was observed in fields of engineering (N = 23), psychology (N = 22), and social sciences (N = 38). Number of publications in engineering are quite noticeable, as in 1970s there were no publications in field of engineering. Other than engineering, QWL research was conducted in various other new fields as well. Such as computer science, earth and planetary sciences, material science, nursing, and pharmacology, toxicology, and pharmaceutics. Another noticeable trend was that United States was still the highest contributing country (N = 34), with much higher research contributions. But number of research contributions from United Kingdom were still same in 1980s (N = 6), as it was in 1970s (N = 6).
Further literature review of top 10 most cited Scopus indexed publications listed in Table 2 indicated that in 1980s along with focusing on perspectives (Nadler & Lawler EE, 1983) and defining (Levine et al., 1984) construct of QWL, researchers started to focus on development (Lawler, 1982;Mirvis & Lawler, 1984;Stein & Kanter, 1980) and current state of QWL in various work environments (Buchanan & Boddy, 1982Kraut et al., 1989;Marks et al., 1986;Mirvis & Lawler, 1984;Smith & Nock, 1980). In 1980s, special emphasis was given to inclusion of advanced technology (Buchanan & Boddy, 1982) and computerization (Kraut et al., 1989) of systems in organizations, and impact of their inclusion on QWL of employees in those organizations (Buchanan & Boddy, 1982Kraut et al., 1989). Results of these studies suggested that inclusion of advanced technology not only enhanced the productivity of organizations and employees, in fact it enhanced their QWL as well (Buchanan & Boddy, 1982Kraut et al., 1989).
In 1980s, employees' perception of QWL was still not clear. A significant difference in understanding of QWL was identified between public and private sector employees (Smith & Nock, 1980). To overcome this conceptual and operationalization gap, researchers suggested various approaches to enhance understanding of QWL construct, and to improve QWL in general (Lawler, 1982;Mirvis & Lawler, 1984). New constructs of QWL were proposed to enrich its definition (Levine et al., 1984). Technological advances (Buchanan & Boddy, 1982, computerized systems (Kraut et al., 1989), and parallel organizational structures were proposed to enhance QWL in general (Stein & Kanter, 1980). In short, focus of 1980s QWL research was mostly on enriching conceptual paradigms of QWL, and developing systems to enhance it on both employee and organizational level.

Focus of Research in 1990s
Bibliometric analysis of Scopus database indicated that researchers' interest in QWL research was reduced to half in 1990s as compared to 1980s. As the total number of publications on QWL reduced to 52 in 1990s. Even the funding sponsors seemed uninterested in QWL, as only three studies were funded in 1990s. Most prominent subject area was still business, management, and accounting (N = 22). Biochemistry, genetics, and molecular biology emerged as a new subject area in 1990s (N = 1). 1n 1990s, United States was still the highest contributing country (N = 27), and contributions from other countries were somewhat equal to each other.
To conclude, various job related and personal antecedents, and various organizational level and employee level outcomes of QWL were identified in 1990s. Figure 2 illustrates these identified antecedents and outcomes of QWL based on top 10 most cited Scopus indexed publications of 1990s.

Focus of Research in 2000s
Bibliometric analysis of Scopus database indicated that researchers' and sponsors' interest in QWL research increased again in 2000s. As total number of publications in 2000s were 87, and 6 out of these were funded. Unlike 1970s to 1990s, most of the publications in 2000s were from field of medicine (N = 37), proceeded by social sciences (N = 26), and business, management, and accounting (N = 22). Health professions, mathematics, and neuroscience emerged as new subject areas in QWL research in 2000s. United States was still the highest contributing country in 2000s with 32 publications.
Further literature review of top 10 most cited Scopus indexed publications listed in Table 4 indicated that in 2000s, researchers mainly focused on filling the gaps in conceptualization (Hsu & Kernohan, 2006;Martel & Dupuis, 2006) and instrumentation (Martel & Dupuis, 2006;Sirgy et al., 2001) of QWL, and its implications in various work environments (Chan & Wyatt, 2007;Gallie, 2003;Huang et al., 2007;Sirgy et al., 2001), especially in fields of medicine, nursing (Gifford et al., 2002;Gurses et al., 2009;Hsu & Kernohan, 2006;Spence Laschinger et al., 2001), and health professions (Krueger et al., 2002). Various countries implemented policies to enhance QWL in 2000s. Gallie (2003) compared employee's perceived QWL between Scandinavian countries and other European Union countries. Perceived quality of work tasks, involvement in decision making, career opportunities, and job security were observed to analyze level of QWL in these countries. In Denmark and Sweden, comparatively higher quality of work tasks, and better opportunities of participation were observed as compared to other countries.
Researchers identified several new domains of QWL in 2000s. The most cited dimensions were of Hsu and Kernohan (2006), Martel and Dupuis (2006), and Sirgy et al. (2001). Sirgy et al. (2001) developed a new measure of QWL based on need satisfaction and spillover theories. The focus of this measure was to capture the perceived need satisfaction of employees from company's work environment, job requirements, supervisory behavior, and ancillary programs. They identified seven major needs of employees with several sub dimensions. These dimensions and their sub dimensions are; health and safety needs (protection inside work, protection outside work, and focus on good health), economic and family needs (pay, job security, and other family needs), social needs (collegiality at work and leisure time off work), esteem needs (work recognition within organization, and work recognition outside organization), actualization needs (potential realization within organization, and potential realization as professional), knowledge needs (learning to enhance job skills, and learning to enhance professional skills), and esthetics needs (creativity at work, and personal creativity and esthetics in general). Martel and Dupuis (2006) identified 33 domains of QWL in general, including; time to perform duties, participation in duties related decision making, skills and worktype fit, autonomy in performing duties, diversity of duties, effectiveness at work, physical requirements to perform duties, work environment, required work-related equipment and tools, feelings of belongingness, emotive power, competitiveness, relations with co-workers, relations with superiors, relations with employer or management, company's policy for family related leave, work performance during one's absence, work allocation during absence of other employees, advancement possibilities, transfers, training and professional development, commitment and evaluation, work schedule, flexible work schedules, role clarity, role confliction, communication and information sharing, income, benefits, income security, relations with union, employee assistance resources. Hsu and Kernohan (2006) however identified 56 categories of nurses' QWL, which could be summarized into six dimensions comprised of; socio economic relevance, demography, organizational aspects, work aspects, human relation aspects, and self-actualization.
To conclude, focus of 2000s QWL research was mainly on instrument development, and testing antecedents and outcomes of QWL in different work settings. Figure 3 illustrates the antecedents and outcomes of QWL based on top 10 most cited Scopus indexed publications of 2000s.

Focus of Research in 2010's
Bibliometric analysis of Scopus database indicated tremendously increased interest of researchers and funding sponsors in QWL research in 2010s. As the total publications in 2010s were 386, and 57 were funded among these. Highest number of publications were again in business, management, and accounting (N = 127). But, a significant increase in publications was observed in fields of social sciences (N = 107), medicine (N = 69), engineering (N = 60), and economics, econometrics, and finance (N = 43). Along with these subject areas, QWL research emerged in various other fields as well in 2010s. Such as: agricultural and biological sciences, chemical engineering, chemistry, dentistry, energy, immunology and microbiology, multidisciplinary, physics and astronomy. Unlike previous decades, in 2010s India was the highest contributing country (N = 69), proceeded by Iran (N = 58), Unites States (N = 46), and Malaysia (N = 21). Publications from other 59 countries were equal to and less than 15 from each. Further literature review of top 10 most cited Scopus indexed publications listed in Table 5 indicated that in 2010s, focus of researchers was mainly on testing previously proposed antecedents and outcomes of QWL in various work settings Bragard et al., 2015;Holden et al., 2011;Koonmee et al., 2010;Lee et al., 2013Lee et al., , 2015Mosadeghrad et al., 2011;Nguyen & Nguyen, 2012), and proposing new ones (Gillet et al., 2013;Koonmee et al., 2010;Mosadeghrad et al., 2011;Nguyen & Nguyen, 2012). Ecept one study which only examined the QWL of nurses in Saudi Arabia . Most of the top cited studies on QWL in 2010s were conducted on health care professionals (Bragard et al., 2015;Mosadeghrad et al., 2011), especially nurses Gillet et al., 2013;Holden et al., 2011;Lee et al., 2013), fewer were on organization's employees (Koonmee et al., 2010;Nguyen & Nguyen, 2012).
To conclude, various organizational and personal antecedents, and various employee level outcomes of QWL were affirmed and identified in 2010s. Figure 4 illustrates the antecedents and outcomes of QWL based on top 10 most cited Scopus indexed publications of 2010s.

Focus of Research in Early 2020s
Bibliometric analysis of Scopus database indicated that in early 2020s significant amount of funded research was conducted on QWL. As the total publication in early 2020s were 102 and more than one third (N = 40) of these publications were funded. Indicating the increased interest of funding agencies in QWL. Most of this research was conducted in the field of business, management, and accounting (N = 35), followed by medicine (N = 26), and social sciences (N = 21). Veterinary emerged as the new subject area in QWL research in early 2020s. Unlike previous decades, Indonesia (N = 15) was the highest contributor of QWL research, followed by Iran (N = 14), India (N = 13), and Malaysia (N = 12).
In remaining two most influential studies of early 2020s, one tested the QWL scale developed by Sirgy et al. (2001) in Brazil and Portugal, and deemed it as a reliable and valid scale in these two countries (Sinval et al., 2020). The other only observed the current status of QWL of employees in Saudi Arabia (Allam & Shaik, 2020). To conclude, various employee level outcomes of QWL were affirmed in early 2020s, and several new organizational and personal antecedents and employee level outcomes of QWL were identified. Figure 5 illustrates the antecedents and outcomes of QWL based on top 10 most cited Scopus indexed publications of early 2020s.

Conclusion, Limitations, and Future Recommendations
Bibliometric trend analysis of QWL research throughout its decades revealed that since the origin of QWL research, mostly research was conducted in the discipline of Business, management, and accounting, followed by social sciences, and medicine (As indicated by Table 1 in Appendix). Initially most of this research was produced from United States, this trend sustained until 2000s, as majority of publications in 2010s were contributed from India. Later on the contributions from other Asian countries increased in early 2020s (As indicated by Table 3 in Appendix). Hence, currently Asian countries are the main contributors of QWL research. Furthermore, most of this is funded by agencies (As indicated by Table 2 in Appendix), indicating the increased interest of government and corporate sectors in QWL of employees.
Further literature review of most cited publications on QWL, revealed that during initial phases of QWL research focus of research was mainly on construct exploration, conceptual development, and identification and eradication of QWL issues on employee and organizational level (As indicated by most influential studies of 1970s and 1980s). Later on in 1990s, researchers started to focus on identification of antecedents and outcomes of QWL. From 1990s to early 2020s several new antecedents and outcomes of QWL were identified (These identified antecedents and outcomes are enlisted in Figures 2-5). Figure 2 indicates that in 1990s most influential researches were quite diverse in their focused areas. As researchers explored various antecedents and outcomes of QWL both at employee level and organizational level during 1990s. But in later decades the contribution of these antecedents and outcomes reduced to some extent (As indicated by enlisted antecedents and outcomes in Figures  3-5). Although various organizational level and personal level antecedents were explored by the researchers from 2000s to early 2020s, but only employee level outcomes of QWL were explored in these decades. Moreover the mostly those factors were observed which could enhance the QWL, and less emphasize was given to the factors which could be harmful for the QWL of employees (Refer to Figures 3-5). Same goes for the outcomes of QWL. The focus was mainly on positive consequences of enhanced QWL. Hence, the QWL research has reached on a certain saturation point as repetitive factors are being focused in the QWL research as it is progressing. As only three new antecedents and two new outcomes of QWL were contributed in early 2020s.
So, there is still room for further exploration. Especially in personal preceding factors, and organizational outcomes of QWL. Furthermore, the emphasis should be given to the Note. TC = total citations; QR = quartile rank; GS = Google scholar rank; TCY = total citations per year. identification of preceding personal factors, because terms such as QWL are mostly subjective in nature. Although there are several objective factors (Adhikari & Gautam, 2010), but those factors are mainly affected by subjective factors, such as employees' perception, and satisfaction from their work environment (Rose et al., 2006). Moreover, future researchers should also work on identification of suppressors of QWL and negative consequences of lower QWL. So, that they could be avoided in order to maintain higher QWL in organizations.
As the most influential research only highlighted the most researched areas, so, it was not sufficient to guide for future research areas. Further keyword analysis was performed to better address the sixth research objective and highlight the research areas which were least focused in QWL research. These keywords are enlisted in Table 4 of Appendix in order of their occurrence frequency. These keywords occurrences suggest that the least researched factors which require further exploration are: family, compensation, attention, affective commitment, psychological adaptation, salary, organizational performance, occupational diseases, and interpersonal communication, quality of health, health, health status, and health care.
Hence, future researchers should try to explore family related influencing factors and outcomes of QWL, such as: family support, family to work conflict, dependents care, satisfaction with family life, spousal relationships, and efficacy in fulfilling family responsibilities. Researchers should also explore health related antecedents and outcomes of QWL both at organizational and personal level. Such as: lifestyle, eating habits, nutritional status, chronic diseases, mental health, and psychological wellbeing. Plus various other organizational factors should be considered by researchers which are directly related to job and organizational performance, and should be tested as individual factors rather than dimensions of other constructs. Moreover, there is a need to test these factors at a large scale in various disciplines and countries, while maintaining higher research quality. As these factors has not been focused by most influential studies. These quality studies will not only aid in identifying the contribution of these factors, but will also facilitate in enhancing employee's QWL at a much larger scale. Furthermore, identification of organizational level positive and negative outcomes of QWL will motivate the organizations to emphasize QWL of their employees. Plus, organizations might increase their focus on introducing employee friendly policies to boost QWL of their employees.