Adaptation: Retrospection of a Decade

Expatriate adaptation refers to degree of fit between the expatriate's ideal requirements and his new environment. Extant literatures indicate that the success of multinational operations is overall dependent on successful adaptation of expatriates. However, as expatriate adaption evolves as an important subject in international management research, salient emerging issues need to be highlighted for the attention of researchers and industry players. This systematic review aggregates a decade (2012 – 2021) depth research. Systematic search was conducted on Scopus on 28th October 2021 and repeated accordingly on 3 rd January 2022. Whence, 2,967 records were extracted. The methodology is based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses ( PRISMA) framework which emphasizes methodological steps of identification, screening, eligibility and included and ensures transparency and comprehensive reporting for critical judgement. Following the review panel parameters of inclusion and exclusion criteria, 67 articles were explored. Hence, descriptive analysis showed steady rise in research publications. 88% of the records found were empirical. Literature classification and analysis identified six (6) emerging themes including yopatriates, flexpatriates, female expatriates. academic expatriates, dual career couple expatriates, and expatriate hostile environment. We recommend investigation into these emerging themes in order to determine adaptation intricacies in each domain.


Introduction
Arising from renewed crave for foreign direct investment FDI into emerging economies (Fu et al., 2021;Nwosa, 2021) coupled with the wave of globalization which has continued to shrink the global investible economies (Munck, 2021;Kierner, 2018;& Brookfield, 2016), the theme of international business management is gaining momentum. The world is technically shrinking through globalization and becoming more connected into one common seamless market (Daher, 2019). Hence, movement (expatriation) of professionals, talents, technology, and expertise across international boundaries has continued to surge (Baruch et al., 2016;Faeth & Kittler, 2020). Although, serious activities are taking place, what specific evolutions with respect to expatriate adaptation has really emerged over the last decade is an unanswered query. Even though successful international management depend on effective adaptation of expatriates. Since the 1991 seminal work of Black et al, on adjustment with its attendant limitations (Haslberger & Dickmann, 2016) and subsequent responses to the gaps identified by those studies, several recommendations have been made for further inquiry into expatriate adaptation overtime. This paper is an attempt to systematically review extant literatures within the spheres of expatriate adaptation between 2010 to 2021. SLR provides a way to assess the quality level and magnitude of existing evidence on a question or topic of interest and offers a broader and more accurate level of understanding than a traditional literature review (Pati & Lorusso, 2018). This periscopic but systematic review will unveil the focus and advances in major studies that has been attained under expatriation within years under review. This effort will unfold a gap for further studies into specific areas and themes of expatriation that have been under researched or even neglected during the decade under review. It is fascinating to note that organizations can no longer ignore the effects of globalization and the increased mobility of labour across national and cultural boundaries (Beechler & Woodward, 2009). Emerging economies relies on global knowledge and skills (Kloss, 2010) while expatriates serve as bridge for the knowledge transfer (Laksani, 2021). Hence, the notion of expatriates' adaptation is becoming more topical. Given these, the number of expatriates globally has been growing steadily during the last two decades (Miocevic & Zdravkovic, 2020) and would continue as long as the need arises for knowledge and expertise transfer across international boundaries (See figure 1). Hence, investigations would ever be crucial to track the intricacies with respect to adaptation of expatriates. Expatriation assignments certainly requires adaptation to multiple environments and aligning to new cultures, languages, and social encumbrances. According to Finaccord (2018) the global expatriate population has reached 66.2 million and is on track to rise to 87.5 million by 2021 with the highest numbers of expatriates residing in Saudi Arabia, the UAE and Germany. In UAE, expatriates made up 87.8% of the total population. For the global figures, individual workers account for over 70% of expatriates and students for 8.5% of them. Evolving a competitive workforce abroad is a relevant challenge to organizations globally especially those with multinational activities and subsidiaries (Nunes et al., 2017). In Finaccord (2018), global mobility is expected to continue to grow over the next few years and expatriates will constitute a large and diverse market. Noticeably though, considerable efforts have been made regarding expatriate adaptation, not much attention has been devoted to expatriation issues in Africa. Zhong et al (2021) submitted that expatriation discourse has attracted significant attention but most of the studies focused on developed countries instead of emerging markets. How multinational enterprises manage their expatriates and conduct businesses through outward foreign direct investment (FDI) is understudied. Hack-Polay (2020) added that extant literatures are largely Western-centric, having more prominently considered the experiences of Western expatriates. As a further limitation to the existing body of knowledge on expatriate' adaptation, popular dimensions of the available studies from the surface centred on cross-cultural differences, language assimilation, knowledge transfer, and expatriates. Job performance enhancements. According to Claus et al (2011) most researchers of expatriate performance management have majorly focused on predictors of expatriate job performance (Ali et al, 2003;Van der Zee et al, 2005) and the link between employee adjustment and performance.

Key Concept Clarification
Expatriate adaptation interchangeably called expatriate adjustment (Haslberger, 2008) is the process by which persons under legal international assignment acquaint themselves to a new environment. It is the degree of fit between the expatriate and the new environment in both work and nonwork domains or the perceived degree of comfort and familiarity with the foreign culture (Aycan, 1997; Lee & Liu, 2006). Though more prevalent, the significance of expatriation is not limited to multinational corporations, it also applies to small and medium enterprises (SMEs) and non-profit organisations (NPO) that are operating at international scale (Siljanen & Lamsa, 2009;McNulty et al, 2017).

Methodology
For the purpose of undertaking systematic literature review on expatriate adaptation over a period 2010 to 2021, Preferred Reporting Items for Systematic Literature Review and Meta Analysis (PRISMA) framework is adopted. PRISMA framework ensures clarity, transparency and complete reporting of systematic reviews that enable readers to critically judge the available evidence and replicate or update the research (Liberati et al., 2009). It is built on four methodological steps of identification, screening, eligibility and included. PRISMA, first published in 2009 strengthens and streamlines the methodological rigor and quality of SLRs and is presented methodically and analytically in a flow chart. As a prologue to the implementation of PRISMA, the review panel set the parameters and protocols that guide subsequent actions. The limitations include access, review coverage in years, article type. Keywords, as well as defining inclusion and exclusion strategies. This protocol definition provides shield against researchers' biases and compromise and provides the ground for sound, lucid and creative literature review process.

Records Removed After Title and Abstract Study
Parameter: Not Suitable to the objective and established protocols by the review panel.

Search Strategy
To forestall predatory resources and ensure quality review, the review panel recommended search from Scopus database only. Scopus is a bibliographic database containing abstracts and citations for academic publications with approximately 11,678 publishers, of which 34,346 are peer-reviewed journals in top-level subject fields. It provides a more comprehensive and wider range of scholarly information and cutting-edge research articles and other academic resources than many other databases. The initial search based on the following search keys (see Table 1) turned out two thousand three hundred and thirty-eight (2,338) resource documents on Scopus. The initial search query string was (TITLE-ABS-KEY) and two (2) Boolean operators "AND" and "OR" as TITLE-ABS-KEY ((expatriat*) AND (adaptation OR adjustment OR assignment OR management)) accordingly. Source: Authors' Systematic Review (2021) NOTE: Major search item "expatriate" was truncated as "expatriate*". Hence, extended versions of the term are considered in the search.

Selection Criteria
Aligning with Page et al (2021), selection of relevant articles on expatriate adaptation for this systematic review was done carefully and based on the following standards. Only resources with Open Access are included. The search was narrowed to include publications between years 2012 -2021 only. Subject areas were streamlined and limited to Business, Management, and Accounting, Social Science, Arts and Humanities, Economics and Finance, and Psychology only. For document type, Articles, Books, and Book Reviews only fulfilled the protocol of the review panel. Publications that have reached final stage and published in English language made the review selection. A total number of ninety-four (94) resources were systematically extracted at this stage.

Quality Assessment
To ensure quality, recency, and regularity the review was limited to extracting records from twenty-two (22) choice prominent academic publishers that have published resources during the period of investigation. These journals are part of the year 2020 Scopus updated list which is latest. Upon scrutinization based on titles and abstract contents, another set of thirty-two (32) articles were dropped for not meeting the requirements and standards set by the review panel. Hence, the number of articles that made it to final review list were sixty-three (63). Others are Universiti Kebangsaan Malaysia Press (2), Editura Lumen (2)

Data Extraction
At this stage, following the parameters set by the review panel, books, book chapters and reviews were excluded, leaving the systematic review with fifty-seven (57) articles in line with the following extraction characteristics: 1. Article must be original, and peer reviewed. Thus, case studies and review were excluded. 2. Article must be in English language and in the field of Business, Management, and Accounting, Social Science, Arts and Humanities, Economics and Finance, and Psychology only. 3. Publisher(s) must be on latest Scopus listing. It can be observed that prior to 2016, bearing the criteria for this systematic review in mind, not much research was held in the domain of expatriate adaptation. The analysis shows that 2019 had the peak while the trend has taken downward dimension indicating that serious effort needs to be made by scholars to investigate this important subject matter.

Figure 3: Distribution of Articles by Type of Research Source: Author's Systematic Review
From figure 3 above, 85% of the publications on the current theme during the period under review are empirical. Although empirical analysis essential and required to validate or criticise overall the existing theories, models or framework, conceptual research is also germane to reinvent and re-establish new research agenda. It is used to develop new theories or interpret existing theories in a different light. Conceptual research also provides new frameworks to guide on the newest direction, thinking and action. Future research may need to take deliberate focus on conceptual studies to lessen the current disproportionate research designs around expatriate adaptation. While qualitative research describes quantitative research defines. Figure 4 above indicates that 41 articles out of 67 considered in this systematic review are rather qualitative based with merely 26 being quantitative. Qualitative studies are required when focus is on exploiting deeper insight into conceptualisation of variables. However, validation in terms testability and verifiability of claims are absent. These limitations give rise to subjectivity and widespread inconsistencies in similar studies. With the seeming imbalance between qualitative and quantitative studies in this systematic review, more quantitative studies that will apply statistical techniques to measure, test and draw plausible inferences with precision are required. The implication of this is that in quantitative studies, a researcher is objectively detached from the subject matter being researched. In general, however, use qualitative research at the beginning of the design process to uncover advances and complexities. At the end, use quantitative design to measure improvements without bias. Expatriates can be classified on the basis of type or nature of appointment. In this review, 76% of the expatriates are assigned while 24% are self-initiated. The implication of this dichotomy is that when MNC are looking for experienced expatriates they usually prefer assigned expatriates (Suutari et al., 2018). Assigned expatriates are employees sent abroad by companies to work on their contracts or subsidiaries while self-initiated expatriates are individuals who travel abroad on their own to look for available jobs (Andresen et al., 2013).

Literature Classification, Discussion of Findings and Future Research
Overall, this systematic review identified different important themes under which expatriate adaptation and management is studied over the decade of the review. For example, Ali et al (2021) reported significant influence of job insecurity and employees' perceptions on expatriate work engagement and knowledge sharing; Duarte et al (2020) found that previous international experience and culture attraction for the host country does influences salary expectations for potential expatriate postings; Lauring et al (2019) reported proactive personality and self-control have favourable effects on expatriate job performance and effectiveness. It is intriguing to note that majority of the articles cited here reported positive association between IHRM policies and practices with expatriate adaptation, job performance and job effectiveness.

Assigned Self Initiated
Another expatriate proxy that received considerable attention is female expatriate. Shortland (2021) under the precincts of rational theory observed that couples engage cooperatively in their division of labour to maximise lifetime earnings, with women prioritising home and family over career prospects. David et al (2019) submitted that perceived organisational support (POS) did not significantly increase adaptation and subsequent longevity attitudes for female expatriates. However, family support and organisational cultural intelligence does. Shortland (2021) indicated that long-term assignments enable female expatriates to maximise or achieve high levels of both career and family outcomes. Shortland and Perkins (2020) found that early-career stage female expatriates believe that equality/diversity policy implementation will support their international careers while senior levels female expatriates highlighted unequal treatment, breaching trust in delivery of equality/diversity principles affect their career progression. Others female expatriate articles systematically analysed include (Shortland, 2020;Isaakyan and Triandafyllidou, 2019;Bader et al., 2018;Shortland and Perkins, 2016;Shortland, 2016;Shortland 2014). Another prominent surrogate in this systematic review is culture as an antecedent of adaptation. Cross cultural integration is a very important factor in expatriation discourse (Paulus & Muehlfeld, 2017). Rao-Nicholson et al (2020) showed that exploration mode of expatriate adjustment substantially improves expatriate behavioural adaptations. Waxin et al (2020) found that thorough orientation programs, cultural orientation, couching and mentoring and team works enhances expatriates' socialization. Giorgi et al (2020) reported positive correlation between cross-cultural adjustment (CCA), perceived organisational support (POS) and innovation and that host country culture is related to cross-cultural competence (CCC). Whereas expatriates' CCC is significantly influenced by multicultural team effectiveness and interpersonal skills (Abugre & Debrah, 2019). Here too, it is obvious that most of the reviewed studies reported correlational and causal/effect relationship between culture and other organisational and interpersonal variables measured along with it. Additionally, knowledge management was found as another antecedent of expatriate adaptation (Soniewicki & Paliszkiewicz, 2019). In this systematic review, Patel et al (2021) showed that Indian IT firms mostly transfer knowledge from their headquarters in the parent country to their subsidiaries in the host country using the onsite-offshore model where work is divided and coordinated between team members situated between the two locations. Harzing et al (2016) indicated in a survey of over 800 subsidiaries of multinational enterprises in 13 countries that expatriate adaptation generally increases functional knowledge transfer flows between headquarters and subsidiaries. Transnational education though old is in recent times generating intriguing discourse among scholars. Perhaps because it creates overwhelming and far-reaching implications for all those involved.  reported positive relationship between cultural competence and adjustment among 103 academic expatriates surveyed in Dubai. Ramalu and Subramaniam (2019) found that psychological needs satisfaction (PNS) partially mediates the relationship between cultural intelligence (CQ) and work engagement (WE) among academic expatriates. In subsamples survey of 792 local and 620 academic expatriates, Jonasson et al (2018) observed that inclusive and empowering management (identity-blind) has significant influence on job engagement and stress in both subsamples while English management communication (identity-conscious), increases stress for local academics but has no effect on expatriates.

Conclusion
This systematic review has proven the significance of expatriate adaptation research in the sphere of international management. The review has been able to identify emerging concepts and themes that require further studies because of their ascendancy role in achieving seamless expatriate adaptation. Further specific investigations to be conducted include whether adaptation process and requirement differ for the emerging themes such as yopatriates and flexpatriates, between female expatriates and dual career expatriates, and between expatriates in hostile environ