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Social media and professional development: a systematic review

Research in Learning Technology 2019. © 2019 C. Bruguera et al. Research in Learning Technology is the journal of the Association for Learning Technology (ALT), a UK-based professional and scholarly society and membership organisation. ALT is registered charity number 1063519. http://www.alt.ac.uk/. This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), allowing third parties to copy and redistribute the material in any medium or format and to remix, transform, and build upon the material for any purpose, even commercially, provided the original work is properly cited and states its license.


Introduction
The intensive and widespread use of digital technologies by today's society has modified and expanded the way in which people communicate and learn (Donelan 2016). Nowadays, citizens use these technologies for multiple purposes, both in their personal and professional spheres (Hunter and Hall 2018). For professionals, this digital transformation has also meant the need to continuously update their professional knowledge and skills to meet the challenges of the digital era, in what is framed within the idea of 'lifelong learning' or 'professional development' (Collin, Van der Heijden, and Lewis 2012).
Social media have emerged as a prominent element of digital technologies that can be defined as global digital communication platforms. These platforms, which connect large numbers of users producing and exchanging user-generated content, seem able to offer sustainable support for professionals' lifelong learning, thanks to characteristics such as the ease with which users are able to create and share content, the breaking down of space and time barriers, and the flexibility and high customisation that its contents and services allow (Ngai, Tao, and Moon 2015;Pérez-Latre, Portilla, and Blanco 2011;Zimmer and Proferes 2014).
Numerous literature reviews have been conducted since the emergence of social media at the beginning of the 21st century, with the purpose of exploring the opportunities offered by these media for learning and updating for professionals. Recent years have seen a proliferation of reviews from health sciences (Cheston, Flickinger, and Chisolm 2013;Curran et al. 2017;Lawson and Cowling 2014;Roberts et al. 2015;Sterling et al. 2017) and education sciences (Gao, Luo, and Zhang 2012;Ranieri 2015, 2016;Tess 2013).
The particular interest in these two fields of knowledge may be explained by diverse factors. In health sciences, as highlighted by some authors of previous reviews, participation of professionals in professional development activities is sometimes required, whether in courses, conferences, journal clubs or other activities. Another main interest lies in the support that social media can offer to keep up-to-date with current clinical evidence and support the exchange of best professional practices. In education sciences, some authors highlight the teachers' interest in incorporating social media platforms into their professional practice as education tools; interest in using social media to exchange professional practices, evidence and resources; or interest in using social media to enable sustainable networks among professionals. Furthermore, in both fields the use of social media for professional development is also highly valued for helping to overcome geographical, temporal and economic barriers.
The number of literature review-based studies and the results of these studies indicate a research field that is growing and beginning to have an abundant body of data, although reviews mentioned focused in a period of time prior to 2015. Due to the constant developments of social media platforms and the increasing use made by society and its professionals, it is worth considering how research in social media and professional development has evolved in most recent years, from a multidisciplinary prism.
Building on the previous literature reviews and based on some of the most relevant types of information considered in those previous reviews, the aim of this article is to review and analyse the scientific literature on social media and professional development published between 2013 and 2017, to identify and summarise the main characteristics, draw conclusions and point to trends in this field of research.

Methodology
A systematic review provided a summary of the research literature, quantitative and qualitative, using explicit and replicable methods to identify and select relevant studies and objective and replicable techniques to analyse and summarise these studies (Arksey and O'Malley 2005;Cooper 2017).
In line with these authors, a number of steps were followed to ensure a systematic literature review. We describe them below.

Formulation of the research objectives
The first step of the systematic review was to formulate the research objectives. We aimed to identify and summarise the years, journals, conceptual background, research 3 (page number not for citation purpose) methodologies, research methods, data collection tools, professional disciplines, educational contexts, types of social media and characteristics of social media capable of generating learning opportunities used in research articles in social media and professional development published between 2013 and 2017.
The key research question we wished to answer was this: What were the main characteristics of the scientific literature on social media and professional development published between 2013 and 2017?

Parameters of the search for articles
The second step of the systematic review was to establish the parameters of the search for articles. To ensure a comprehensive data collection and a multidisciplinary approach, we searched for articles that were indexed in two social sciences reference databases: 'Scopus' and 'ISI Web of Science'. The terms used to search for articles consisted of, on the one hand, a combination of the keywords 'social media' and 'social networks', and a combination of the keywords 'lifelong learning', 'professional development' and 'professional updating', on the other. The use of these terms allowed us to align our search with the search strategies conducted in the previous literature reviews.
The articles chosen had to satisfy the following specific criteria: 1. focus on the relationship between social media and learning; 2. learning approach including professional updating and the lifelong learning of professionals; 3. reporting of empirical data; 4. publication in a journal indexed in Scopus or ISI Web of Science between 2013 and 2017 or identification using the snowball sampling method; and 5. availability in English or Spanish.
In addition, the full text of the article had to be available through the researchers' institutional library subscriptions.

Selection of the studies
The third step of the systematic review consisted in selection and compilation of the studies. The first database consulted was ISI Web of Science. A first search produced 328 results. The results were then filtered by article, reducing the results to 241. Filtering by language to English and Spanish reduced the number of articles to 228. In a first round of reading the abstracts, the filtered results were compared with the established criteria, and the number of articles was reduced to a total of 56. In a second round of a complete reading of the articles, that total was reduced to 30.
The second database consulted was Scopus. A first search produced 426 results. The results were then filtered by article, reducing the number of articles to 262. Filtering by language to English and Spanish reduced the articles to 257 articles. In a first round of reading the abstracts, the filtered results were compared with the established criteria, and the number of articles was reduced to a total of 52. In a second round of a complete reading of the articles, that total was reduced to 34. Some articles were also selected using the snowball sampling method: the bibliographic references of the articles previously selected were consulted to obtain an additional four articles of interest.
Any duplicate articles (appearing in both databases) were then merged, leaving a final selection of 44 articles. The articles were compiled in Mendeley, and the information were extracted and organised in an extensive spreadsheet.

Data extraction and research analysis
The fourth step of the systematic review consisted of extracting and analysing the information from the selected studies. Before applying the analysis, we decided on the type of information to be extracted from the articles. The name or label of the type of information 'should be suggested by the context in which the event is located' (Strauss and Corbin 2002, p. 116).
Firstly, the 44 articles were collected and organised with the bibliographic data, including article title, authors, journal, abstract, keywords and publication year. Then, 10 additional categories related to the articles were coded, based on those considered in the previous literature reviews, to obtain relevant data useful to cover the basic characteristics of research on social media and professional development. Finally, information from each publication was organised according to the following criteria: (1) year, (2) journal, (3) conceptual background, (4) research methodologies, (5) research methods, (6) data collection tools, (7) professional disciplines, (8) educational contexts, (9) type of social media and (10) characteristics of social media capable of generating learning opportunities.
The different types of information were extracted from the articles in the form of categories. The objective of categorising the types of information was to 'obtain key elements of the information obtained in the research articles' (Arksey and O'Malley 2005, p. 26). A qualitative content analysis was performed. This enabled the information to be organised into categories and subcategories for further analysis (Gibbs 2012). In this qualitative analysis, 'data are broken down into discrete parts, closely examined, and compared for similarities and differences' (Strauss and Corbin 2002, p. 111).

Presentation of results and interpretation
The last step of the systematic review consisted of interpretation of the evidence and presentation of the results. Due to the broad scope of this phase, the results are presented in the following section, with the different types of information analysed organised in separate sections, and using descriptive statistics for more effective description and visualisation.

Results
In this section, we will present the results of the study, organised by the types of information indicated in the previous section.

Years
The articles reviewed were published between 2013 and 2017 ( Figure 1).

Journals
The articles were published in 40 different journals. Figure 2 shows the distribution of the articles in journals with two or more articles identified in our review. Three of these journals are relevant to education sciences and two to health sciences.

Conceptual background
To understand how the different research is conceptually framed, another type of information extracted from the articles and subjected to a categorisation process was the set of conceptual backgrounds of the different articles (Table 1).
By 'conceptual background', we refer to the concepts that served as an umbrella to the different empirical studies, provided these were made explicit by the authors of the articles. Concepts that were not clearly specified were categorised within the 'Not specified' label. Those closely related were grouped into broader categories. The list is not exhaustive.

Research methodologies
The studies reviewed used qualitative, quantitative or mixed methodology to carry out their research, as shown in Figure 3.

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Community of practice (CoP) 'Learning model based upon the principles of apprenticeship, and cooperative learning' (Davis 2015(Davis , p. 1552.

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Affinity spaces Digital spaces 'where users can interact around topics of shared interest' (Carpenter 2015, p. 211).

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Lifelong learning approach Broad term that encompasses learning throughout life, from early childhood through adulthood (Weber and Vincent 2014).

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Journal clubs Regular meeting of a group of professionals to critically evaluate recent articles in academic literature (Roberts et al. 2015).

Research methods
The research methods were also identified, as shown in Figure 4. In this respect, a number of emergent methods related with social media research were identified alongside 'traditional' scientific research methods such as surveys 7 (page number not for citation purpose)  and interviews, in contrast to the methods found in previous literature reviews. One of these emergent methods is social network analysis (SNA), a methodology for examining the interaction patterns that occur within a group of users, and which is 'very suitable for the analysis of large quantities of data' (Rehm, Littlejohn, and Rienties 2018, p. 311). This is also the 'digital methods' label, which designates 'a term that seeks to capture a recent development in Internet-related research related to the internet, summarised as approaches to the web as dataset' (Rogers 2005, p. 1, cited in Hutchinson 2016, p. 1).

Data collection tools
In addition to the methodologies and methods, the data collection tools used in the studies were also identified. A distinction must be made between the kind of data obtained through, for example, Twitter or LinkedIn web analytics, and data obtained from content generated and shared on social media through, for example, Twitter posts, YouTube comments or Facebook chats ( Figure 5).

Educational contexts
The educational contexts addressed in the set of articles were also identified, as shown in Table 2. To extract the information related to these contexts, the articles were categorised according to whether they focused on a formal, non-formal or informal learning context. González-Sanmamed et al. (2018) offer useful definitions of each context. Formal education can be defined as 'formal training that takes place in different organised and structured environments' (p. 24). Non-formal education, also known as organised informal education, can be defined as 'activities organised by different institutions that take place outside of what is recognised as regulated training, and may or may not lead to the attainment of a certificate' (p. 24). Informal education can be defined as the 'day-to-day learning that occurs in everyday situations (with family, friends, co-workers, etc.). This is not organised, and can occur by chance, in which case it is called incidental' (p. 25).

Types of social media
The different social media platforms addressed in the set of studies were also identified (Figure 7).

Professional disciplines
Professional disciplines that were the subject of study in the set of articles were also identified and categorised. This categorisation is shown in Figure 6.

Characteristics capable of generating learning opportunities
The characteristics of social media that are able to generate the learning opportunities for professional development specified in the conclusions of the set of studies were also categorised. By 'learning opportunity', we refer to situations in which learning can be activated. To categorise these characteristics, the Social Media for Learning (SM4L) framework was used. The SM4L framework aims to demonstrate how students and academics can use social media to promote learning (Middleton and Beckingham 2015); for this study, the original framework was adapted for a professional context. Firstly, the characteristics identified were categorised using the original SM4L framework. Then we removed, modified and added categories and subcategories in a new adaptation, following the qualitative content analysis previously described. Table 3 shows the most-found characteristics of social media capable of generating learning opportunities as identified in the set of articles. Each characteristic has  been counted independently, more than one characteristic having been identified per study. The list is not exhaustive.

Discussion
This article highlights several points regarding research into social media and professional development. We describe them below.

Upward trend in research into social media and professional development
Firstly, we observed a mostly upward trend in the number of publications during the delimited period from 2013 to 2017, with a slight setback in 2016. The number of articles identified in recent years helps to overcome the 2015 barrier of previous literature reviews and serves to address the need for empirical studies on social media and learning research, which has been pointed out by some authors (Tess 2013). The wide variety of journals in different fields that published the revised articles -35 in total -is noteworthy. Five journals contributed two or more articles to this review: three from educational sciences and two from health sciences. This increasing number of articles and the great variety of journals that have addressed this field of knowledge seem to indicate an interest in line with the popularisation of social media and the immense amount of space that these media have come to occupy in people's lives (Smith and Anderson 2018).

Strong social component of conceptual backgrounds
We analysed the conceptual approaches of the studies, as long as the authors made it explicit. That was useful to frame social media in the research field and better understand the author's point of view. In the first place, it should be noted that, in almost a quarter of the articles reviewed, the conceptual approaches were not clearly stated beyond a general reference to a particular field of knowledge. Among the articles that made their conceptual background explicit, personal learning environments (PLEs) and personal learning networks (PLNs) were the most-used conceptual frameworks when placing social media in the educational process, especially in a formal context. Other concepts and terms with a marked social component such as 'communities of practice', 'affinity spaces' or 'journal clubs' have acquired a remarkable presence.

Surveys, the main research method for collecting social media data
There is a certain balance among the reviewed articles regarding the use of quantitative, qualitative and mixed methodologies, though the quantitative methodologies are the most prevalent among the set of studies. Of these quantitative methodologies, the survey method was by far the method most used, with questionnaires being the form of data collection most frequently used for obtaining data relevant to social media and learning: more than half of the reviewed articles used questionnaires to collect data, which aligns with results of previous literature reviews. However, a number of methods and techniques tailored to digital environments -encompassed in concepts such as digital methods, digital ethnography or SNA -were observed to have emerged.

Health and education sciences remain the most studied fields of knowledge
Most of the scientific research indicated in previous literature reviews was produced in education and health sciences (Cheston, Flickinger, and Chisolm 2013;Curran et al.

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(page number not for citation purpose) 2017; Gao, Luo, and Zhang 2012;Lawson and Cowling 2014;Ranieri 2015, 2016;Roberts et al. 2015;Sterling et al. 2017), probably for the particularities we described in the introduction section. Although our literature review followed a multidisciplinary approach that did not exclude any field of knowledge or professional sector, we were able to observe that the education and health sectors remained the fields with the highest concentration of studies. We can state that most of the interest is still coming from these two fields. Research in the health sector covered the greatest variety of professional disciplines, in a broad spectrum ranging from radiology to paediatrics. Research in the educational sector was focused mainly on higher education, probably because of its greater accessibility to researchers.

Special interest in the informal learning context
There was cross-disciplinary interest in studying the incidence of social media in different learning contexts, though the informal learning context was the most frequently studied. Previous reviews showed a slightly greater interest in the study of social media in formal contexts. In our review, interest in the formal context seemed related to the way in which social media could be effective as an educational tool. In the non-formal context, interest seemed to be related to determining how these media could support and extend 'traditional' learning or professional development activities such as conferences, courses or journal clubs. In the informal context, interest was broader and more diverse. Firstly, there was interest in studying the 'spontaneous' and 'general' use of social media made by users in their daily lives. Then there was interest in the self-directed learning of individuals enabled and empowered by social media. And thirdly, there was also interest in the informal use of social media by citizens in their educational or professional contexts and activities.

Twitter, the most cited social media platform
With respect to social media platforms, Twitter was the most studied social media platform in our literature review. While Twitter was not the social medium most used by Internet users, it seems to have an active presence in the professional life of citizens, serving as a platform for professional global digital communication. This focus on Twitter is aligned with the growing interest indicated in some of the previous reviews (Zimmer and Proferes 2014). Facebook, the most widely used social media platform in general use today (Smith and Anderson 2018), was the most visited platform after Twitter. Twitter may have become the preferred platform over other platforms such as Facebook 'due to advantages such as short-form messaging, easily grouped themes with hashtags, and rapid spread of messages (going viral) with easy sharing through retweeting' (Goodyear, Casey, and Quennerstedt 2018).

Characteristics that generate learning opportunities are markedly open, social and accessible
The many and varied characteristics of social media capable of generating learning opportunities were categorised using an adaptation of the SM4L framework (Middleton and Beckingham 2015). Among the many characteristics to emerge from the set of studies, we would highlight opportunities derived from (1)  with diverse aspects of their profession, overcoming spatial, temporal and economic barriers; (2) the multiple communication and sharing options that these media allow by enabling different forms of interaction between users and (3) by being authentically situated in the professional field and familiar to most users; (4) the diverse types of personal or professional networks facilitated by social media and (5) the user-centred focus, especially conducive to self-directed and informal learning. These characteristics seem defining when thinking about social media for professional development and its applications for professionals' learning and updating.

Conclusions
This systematic literature review analysed and synthesised 5 years of research in social media and professional development, covering years and disciplines not covered in the previous literature review. The review helps to point to the existing academic interest in the possibilities of social media for supporting professionals in their learning and professional development in different learning contexts. Also, it shows the way research has been done, in terms of methodology, and the kind of evidence obtained.
Our review provides new information to that generated in the previous reviews, which did not consider the research carried out beyond 2015. In this sense, we would like to highlight some of the main characteristics found. Firstly, although surveys prevail as the main method to collect data, emerging methods such as digital methods are being increasingly implemented, being indicated as especially useful when analysing the large amount of data generated in digital contexts. Secondly, Twitter has a very prominent situation in the professional context compared to other social media platforms, especially to get updated information useful for keeping up-todate professionally and connecting with other professionals. Thirdly, the study of social media and professional development is focusing more on informal learning contexts. While in previous reviews there was a slightly greater focus on social media within formal learning contexts, many of the authors of our review focus on the informal use of social media and its implications for learning. Fourthly, research in social media and professional development is still addressed primarily in the fields of education and health, although in our review we observed a growing interest in other professional fields, such as social work, librarianship, Science, Technology, Engineering and Mathematics (STEM) disciplines, forestry and music.
From the review we conducted, we also observed that numerous empirical studies coincide in indicating that social media can be a useful communication platform and serve as open and rich digital spaces for professionals to exchange information, opinions and ideas. Overcoming geographical, temporal and economic barriers is one of the key points to use them for professional development purposes. In addition, the speed with which social media content is updated is pointed out as also very relevant, though we also found serious concerns about what are referred to as privacy conflicts.
Despite the huge popularisation of social media platforms such as Facebook, Twitter, Instagram and YouTube in the last decade, some authors pointed out that research into social media and professional development is still at an incipient stage (Ngai, Tao, and Moon 2015) and, although progress is being made, a greater amount of empirical data still needs to be generated. As an overall conclusion, our findings 13 (page number not for citation purpose) suggest that a considerable amount of data has been generated in recent years, although these data are a bit chaotic and loosely connected. Several points of interest and possible future lines of study emerged from the results of this literature review. Firstly, informal use of social media seems to require further study because much of social media use occurs outside formal and non-formal settings and for purposes other than learning. One question that arises in this respect is whether social media platforms can be incorporated into formal contexts for educational purposes, or whether the true virtue of these media is the informal, spontaneous and self-directed use made of them by their users. More research into social media and professional development outside the disciplines of education and health sciences is also needed to help meet the needs and peculiarities of the different groups of professionals in today's society.
Research into social media needs to acknowledge that social media platforms are constantly evolving and adding new features to their service. Facebook or Twitter today has new features compared to the Facebook and Twitter of 10 years ago. In addition, other digital products, such as WhatsApp or Spotify, are incorporating more and more social network features into their functionalities, making it difficult to mark the boundary between what is social media and what is not. In any case, what seems clear is that the evolution of digital technologies, the social web and mobile devices has fostered a societal need for open, social and accessible platforms of communication that allow us to connect with other people and generate and share content in a simple way while offering us an attractive functionality and design. We believe, then, that research should focus not on specific platforms, but on what these platforms can enable in terms of learning and communication possibilities.
As we have seen from the review conducted, conceptual approaches with a social and technological emphasis such as PLE and PLN, communities of practice and affinity spaces were used to locate social media in the process of learning and updating for professionals. In this respect, the learning ecologies framework -defined by Barron (2004) as 'the set of contexts composed of configurations of activities, resources and relationships that are generated in physical or virtual spaces and that offer learning opportunities' (p. 6) -could be highly useful in determining how professionals currently learn. This ecological vision of how people learn could enable professionals to learn how to organise their learning ecology better, update themselves professionally, understand the role of social media in the framework of their learning ecology and be aware of the benefits these media can offer for their lifelong learning process.

Funding
This work was supported by the Government of Catalonia as part of the 'Grants for the recruitment of early-stage research staff (FI-2018)' initiative.