| Pre-adoption | Compatibility | Cloud computing adoption in SMEs | The degree of perception to consider the adoption of new technology when technology is recognised as compatible with work application systems | Priyadarshinee et al. (2017) |
| Perceived ease of use | User IT acceptance | The degree, to which an adopter believes that using a particular system would be free of effort | Hameed (2012), Davis (1989) |
| Perceived usefulness | User IT acceptance | The degree, to which an adopter pursues a particular technology to the extent at which one believes that it will improve the performance of a task | Hameed (2012), Davis (1989) |
| Flow experience | User IT acceptance | The extent, to which an adopter experiences an optimal mental state of being fully immersed, focused and involved in tasks, activities, or initiatives an adopter is undertaking for the I4.0 implementation | Pilke (2004) |
| Internal information sources | IT adoption by organisations | Internal information that may have been acquired at one time from previous experience and past information searches, or passively through low-involvement learning, where consumers are repeatedly exposed to marketing stimuli | Jeyaraj et al. (2006) |
| External information sources | IT adoption by individuals | External information acquired from the environment, and this represents a conscious effort to seek out new information | Jeyaraj et al. (2006) |
| Observability | | The degree, to which the results of an innovation are observable from those who have already adopted the innovation | |
| Perceived risk | IoT services adoption | The level of an adopter's uncertainty in the aspect of anticipated costs, sacrifices, and losses when a new technology is adopted | Hsu and Lin (2016) |
| Perception of the term Industry 4.0 | Cloud computing adoption in SMEs | The degree of an adopter's awareness of the term “Industry 4.0”, and the extent, to which they evoke technology adoption | Priyadarshinee et al. (2017) |
| Subjective importance of tasks | Innovation adoption | The extent, to which the importance of the task of configuring systems and satisfaction are derived and ranked relative to the importance of and satisfaction with other five tasks: face-to-face selling, sales planning, answering technical questions, administrative work, and other internal work of the corporation | Chor et al. (2014) |
| Technological innovativeness | Innovation adoption; IT innovation adoption in organisations | The extent, at which organisations tap and harness technologies that lie beyond their formal boundaries | Sharma et al. (2016), Chor et al. (2014), Hameed (2012), Rogers (1995) |
| Adoption | Competitive price intensity | Innovation adoption | The frequency of price-cutting taking place at a particular organisation | Chor et al. (2014) |
| The emergence of the global distribution network | Cloud computing adoption in SMEs | The level of existence of a mechanism that helps a supplier widen the range of targets | Priyadarshinee et al. (2017) |
| CEO advocacy | Innovation adoption | The degree, to which the highest official of an organisation provides supportive actions for innovation | Chor et al. (2014) |
| Financial evaluation | Assimilation of innovations in hospitals | The level of the process of evaluating various projects, budgets, businesses, and further finance-related subsidiaries to agree on their viability for investment | Meyer and Goes (1988) |
| Innovation in business models | Prototypical implementation in an industrial machine; innovation of dietary supplement shops; reconfiguration tactics in electric vehicle manufacturers | The extent, to which new technologies or business ideas are translated into new business models including the choice of the organisational type, planning method, the approach to the reconfiguration and development of a convincing value proposition | Jazdi (2014), Christensen et al. (2016), Sosna et al. (2010), Bohnsack and Pinkse (2017) |
| Competitive pressure | Cloud computing adoption in SMEs | The level of pressure made by competitors and felt by the organisation to adopt a new technology | Priyadarshinee et al. (2017) |
| Incentives for the I4.0 adoption | Innovation adoption | The degree, to which the public sector or government provide an effective incentive scheme and share a portion of innovation financial risks through the provision of financial subsidies, low-interest and long-term loans and tax reduction to primarily provide an innovative and competitive avenue for I4.0 adopters | Yigitcanlar et al. (2017) |
| The geographic location of an organisation | Diffusion of knowledge in plant biotechnology; innovation performance of technology-intensive firms | The level, to which the geographical clustering among I4.0 adopters positively influences tacit knowledge exchange through simplified interaction in the form of formal or informal contacts, further characterised by a frequency of interactions and creation of networks for the realisation of innovation | Gallaud and Torre (2005), Martinez-Noya and Garcia-Canal (2017) |
| Customer interaction | A dynamic evolutionary model of demand in long-distance telecommunications services | The degree of advertising, marketing, sales, and customer support activities performed by an organisation to interact with its customers | Manral (2010) |
| Reputation of suppliers | Cloud computing adoption in SMEs | The extent of perceptual representation of an organisation's past actions and prospects that describe the organisation's overall appeal to all of its key stakeholders when compared with other leading rivals | Priyadarshinee et al. (2017) |
| Size of an organisation | Cloud computing adoption in SMEs | The extent, to which I4.0 adopters exhibit tolerance for bearing the cost and the risk of adopting innovations, given the adopter's resources, the volume of transactions, and the size of the workforce | Priyadarshinee et al. (2017) |
| Information systems infrastructure | IT adoption by organisations | The degree of pervasiveness, power, and tight integration among elements of information infrastructure to transfer, store and retrieve, and process information | Jeyaraj et al. (2006) |
| Technical support and expertise | Assimilation of innovations in hospitals; user IT acceptance | The level of proficiency of an I4.0 adopter in the aspect of information technology installation, operation, maintenance, network administration, and security | Meyer and Goes (1988), Hameed (2012) |
| Type of industry | IT adoption by organisations | An industry's level of characterisation by the level of complexity of operations, which calls for the improvement of competitive advantage and the development of the Industry 4.0 competency | Jeyaraj et al. (2006) |
| Post-adoption | Access to I4.0 technologies | Cloud computing adoption in SMEs; smart manufacturing | The degree of availability and acquisition of I4.0 technologies among I4.0 adopters, such as IoT, CPS, smart manufacturing, and cloud computing | Priyadarshinee et al. (2017), Kang et al. (2016) |
| Adaptivity by plug-and-work | Implementation of CPS and CPPS in manufacturing; different levels of applications (e.g., sensor level) | The extent, to which technologies control relevant entities within the production system through convenient plugged in/connectivity to start operations without changing the control applications for the rest of the production system | Monostori et al. (2016) |
| Auditability | Cloud computing adoption in SMEs | The system's degree of efficiency in finding any unexpected information behaviour upon request of the customer to increase trustworthiness | Priyadarshinee et al. (2017) |
| Culture of change | IT adoption by organisations | The extent, to which the organisation responds to a perceived change in demands on the core tasks when aiming at developing a service business | Jeyaraj et al. (2006) |
| Customer co-creation | Conceptual typology ad research agenda | The extent, to which I4.0 adopters perform a collaborative new product development activity, which makes consumers actively contribute and select various elements of a new product offering | Sung (2018), O’Hern and Rindfleisch (2010) |
| Data lifecycle | CPS implementation in factories | The extent, to which elements in the information system can complete the journey of data collection, transmission, storage, pre-processing, filtering, analysis, mining, visualisation, and application | Lee et al. (2015), Tao et al. (2018) |
| Decentralisation | Use of patented intelligence in various fields (e.g., collaborative mass customisation of short lifecycle products) | The extent, to which decision-making is dispersed in an organisation, giving employees greater autonomy and responsibility, and consequently increasing internal information flow | Terziyan et al. (2018) |
| Degree of autonomy | Use of CPS in a distributed control system for an urban vehicle traffic | The level of self-governing capability of a machine with embedded knowledge processing that allows independent decision-making | Letia and Kilyen (2018), Tweedale (2015) |
| Degree of integration | Innovation adoption; user IT acceptance; technology planning process in a private academic institution | The extent of integrating technology into an organisation for effective and diffused use of technology and getting management to the established standards | Hameed (2012), Chor et al. (2014), Gülbahar (2007) |
| Dependability | Creation of CPS; estimation of dependability metrics in virtual network environments | The degree of reliability and availability of information technology tools, which directly impact the quality of service | Alguliyev et al. (2018), Lira et al. (2015) |
| Economies of scale | Cloud computing adoption in SMEs | The level of cost advantage obtained by a firm when the cost per unit of output decreases as production quantity increases | Priyadarshinee et al. (2017) |
| Financial leverage | Impact of innovation strategy in high-level-research companies | The degree, to which an organisation generates profits from the implementation of innovation strategies | Ezzi and Jarboui (2016) |
| Formalisation of systems development | Application of formalisation | The extent, to which an I4.0 adopter can create formally-defined, brand-named, or published development methodologies aimed at descriptions of the current work of users and the organisation, functional requirement specifications, technical design, functional design, code, technical conversion plan, and functional conversion plan, to name a few | Mathiassen and Munk-Madsen (2007) |
| The functionality of service quality | Use of software functionality service in diverse type network technologies (e.g., 3G) | The degree of fitness for a piece of software or how it compares to competitors in the marketplace as a worthwhile product | Salleh et al. (2017) |
| Human in/outside the loop | Smart process control in an experimental office building | The degree of information technologies to integrate humans in the process control loop, that is, interacting with a distant system to accomplish a given task | Aduda et al. (2014) |
| Information intensity | Effect on various industries’ competitive advantage | The level of intellectual work done by I4.0 adopters as they conduct their affairs | Sabherwal and King (1991) |
| Intelligent lots | Batch scheduling problem | The extent, to which technologies deal with batch scheduling problems | Li et al. (2012) |
| Interoperability | Cloud computing adoption in SMEs | The degree of using computational tools to facilitate the flow of work and coordination between organisations | Priyadarshinee et al. (2017) |
| Knowledge transformation | Innovation adoption | The number of new product ideas or projects initiated by an organisation | Chor et al. (2014) |
| Machine flexibility | Classification of flexible manufacturing system types | A machine's degree of ease in making the changes required to produce a given set of part types | Browne et al. (1984) |
| Maintainability | | The degree of efficiency, to which an item will be retained in or restored to a specified condition within a given period when prescribed procedures and resources perform maintenance | Blanchard et al. (1995) |
| Manager risk tolerance | Firms at a particular stock price and firm size data | The degree of I4.0 adopters’ risk aversion and risk perception, which plays an essential role in the decision-making by managers | Frijns et al. (2013) |
| Multilingualism | IT adoption by organisations | The degree of I4.0 technologies to support multiple languages for effective delivery of information and knowledge in CPS | Jeyaraj et al. (2006) |
| Operational risk | | The degree of loss risk from inadequate or failed internal processes, people, and systems, or external events | Hoffman (2002) |
| Organisational efficiency | The stochastic frontier analysis employed by nations | The level, to which I4.0 adopters adopt and adapt the existing technology from world technology leaders and successfully apply it domestically | Danquah (2018) |
| Organisational performance | Empirical data analysis on the role of organisational culture to the improvement of organisational performance | The extent, to which an organisation achieves set objectives of retaining profits, having a competitive edge, increasing market share, and maintaining long-term survival, which depends on the use of applicable organisational strategies and action plans | Oyemomi et al. (2019) |
| Partnerships | Cloud computing adoption in SMEs | The degree, to which I4.0 adopter and suppliers work together to improve their service | Priyadarshinee et al. (2017) |
| Performing trial for the organisation of innovation | Analysis of innovation research in economics, organisational sociology, and technology management | The degree, to which an innovation may be experimented with on a limited basis | Gopalakrishnan and Damanpour (1997) |
| Real-time capability | Use of patented intelligence in various fields (e.g., collaborative mass customisation of short lifecycle products) | The level of a system's ability to update information at the same rate as the event happens | Terziyan et al. (2018) |
| Reduced operational cost | Road-mapping process of a manufacturer of medical equipment and consumables | The extent, to which a resultant cost improvement is achieved when innovation is implemented | Issar and Navon (2016) |
| Remote monitoring and control capability | Conceptual typology ad research agenda | The degree of a system's capability to control large or complex facilities, such as factories, power plants, network operation centres, airports, and spacecraft with some degree of automation | Sung (2018) |
| Research & development intensity | Innovation adoption | The number of organisation-financed business-unit research projects and development expenditures, which are expressed as a percentage of business unit sales and transfers over a fixed period | Chor et al. (2014) |
| Resiliency | Large scale surveys conducted among IT professionals and academics | The extent, to which data centres can withstand any cyber-attacks, floods, fire, theft, server and network failures and natural disasters without losing the ability to provide services or, more importantly, their data | Chang et al. (2016) |
| Supply chain integration | User IT acceptance | The degree, to which an organisation strategically collaborates with its supply chain partners and manages intra and inter-organisation processes to achieve effective and efficient flows of products, services, information, money, and decisions, to provide the maximum value to its customers | Hameed (2012) |
| System robustness | Creation of CPS | The extent of the ability of the system to cope with errors during the execution and cope with erroneous inputs | Alguliyev et al. (2018) |
| Usability | Cloud computing adoption in SMEs | The degree, to which a specific user can use technology for specific organisations with the intent of reaching precise objectives with efficiency, effectiveness, and satisfaction in a determined context | Priyadarshinee et al. (2017), Letia and Kilyen (2018) |
| Work simplification | IT adoption by organisations | The degree, to which information technology replaces the mental component of work particularly in manufacturing applications | Jeyaraj et al. (2006) |
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