| Stakeholders | Akadiri et al. (2013), De Brucker et al. (2013); Frini and BenAmor (2015) and Chowdhury et al., 2020 | Works concerned with sustainable project selection, considering simultaneously the economic benefits, the environmental impacts and the decision-maker preferences |
| Size | Lu et al. (2015), Bjorvatn and Wald (2018) and Safapour et al. (2018) | The size of the project affects complexity and reduces project management performance. This project size also influences project management |
| Interdependencies | Jafarzadeh et al. (2018) and Al Zaabi and Bashir (2020) | The study proposed projects interdependencies between prioritization and uncertainty, which contributes toward project complexity |
| Technology and tools | Tafi (2013); Poveda-Bautista et al. (2018) and Contractor (2018) | Proper technology and tools can be helpful to measure and eliminate project complexity |
| Management decisions | Kermanshachia et al. (2016), Ahmadi et al. (2017); Rumeser and Emsley (2019) and Schultz et al. (2019) | It is noticed that magnitude of change orders from management impacts project execution and complexity |
| Cultural diversity | Arditi et al. (2017) and Trinh and Feng (2020) | Cultural diversity significantly influences the project complexity |
| Variety | Morris (2013) and Stretton (2017, 2019) | Representation of a variety of contexts affects project management. It is essential to sort out who should be involved and in what capacities to effectively managing projects |
| Resources and capability | Darcy et al. (2014); Fores and Camison (2016); Woschke et al. (2017), Nguyen et al. (2019) and Sharma and Naude (2021) | Resource scarcity (e.g. human resource scarcity, financial resource scarcity, etc.) among companies affects the project innovation performance and increases the complexity |
| Uncertainty | Roghanian and Bazleh (2011), Ghapanchi et al. (2012); Taylan et al. (2014), Dandage et al. (2018); Engström et al. (2018) and Hamdan et al. (2019) | An investigation of the common causes of project delays is identified and prioritized based on the simple ranking methods and considering uncertainty in projects |
| Information exchange | Kahraman et al. (2007), Chen and Cheng (2009); Haque and Islam (2018) and Akhavan et al. (2019) | Efficient information exchange among projects can be one of the major enabling factors to achieve a successful project |
| Laws and regulation | Kivila et al. (2017) and Romasheva and Ilinova (2019) | The level of policy incentives and regulations affect the effectiveness of any projects’ implementation, confirming the adequacy of the offered methods and identifies various measures to ensure the project’s success |