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International Journal of Construction Management
ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/tjcm20
Review on criteria for evaluating unsolicited
public–private partnership PPP proposals from
2004 to 2018
Julius Jubilee Nyagormey , Bernard Kofi Baiden , Gabriel Nani & Emmanuel
Adinyira
To cite this article: Julius Jubilee Nyagormey , Bernard Kofi Baiden , Gabriel Nani & Emmanuel
Adinyira (2020): Review on criteria for evaluating unsolicited public–private partnership
PPP proposals from 2004 to 2018, International Journal of Construction Management, DOI:
10.1080/15623599.2020.1783596
To link to this article: https://doi.org/10.1080/15623599.2020.1783596
Published online: 10 Jul 2020.
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Review on criteria for evaluating unsolicited public–private partnership PPP
proposals from 2004 to 2018
Julius Jubilee Nyagormey, Bernard Kofi Baiden, Gabriel Nani and Emmanuel Adinyira
Department of Construction Technology and Management, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
ABSTRACT
Unsolicited projects (USPs) in public–private partnership (PPP) projects need careful assessment and evalu-
ation prior to implementation. Although interests in reviewing general trends in managing Unsolicited
projects of PPP is drawing attentions, there is a lack of a systematic review of PPP literature on critical cri-
teria for evaluating USPs worldwide. This paper aims to address this gap by methodically conducting an
in-depth review through a three-stage systematic process. A systematic desktop search was conducted, fol-
lowed by the selection of related papers on USPs. A list of 27 criteria for evaluating USPs was identified
from 46 selected papers drawn from some selected top tier academic journals from 2004 to 2018 (years
inclusive). The finding shows an increase in criteria since 2005 for USPs evaluation. Most identified criteria
within the time frame of 2004 to 2018 are outstanding innovative proposal, optimal value for money,
appropriate risk allocation mechanism, financial capabilities of proponent, Professional and technical capa-
bilities of proposers, accountability and transparency, intellectual property conditions and competitive bid-
ding procurement among others. This provides an overview of evaluation criteria for USPs. The checklist of
criteria for evaluating USPs could be adopted for further empirical studies.
KEYWORDS
Public private partnership;
unsolicited proposals;
solicited proposals;
evaluation criteria
Introduction
Infrastructure has come to be recognized as a prime driver for
economic growth, and a number of developing countries have
begun adopting new procurement frameworks for enhancing
innovation and efficiency in public infrastructure development
(Verma 2010). Many governments across the globe seek to tap the
private sector’s expertise and capital to minimize their infrastruc-
ture deficit. Against this background some researchers worldwide
attempted to investigate into the implementation and operations
of PPP policy (Chan et al. 2010;Cheungetal.2012; Grimsey and
Lewis 2002). Other different PPP areas extensively explored and
investigated are risk management (Akintoye et al. 1998;Shenetal.
2006), relationship management (Abdul-Aziz 2001;Chanetal.
2003, Smyth and Edkins 2007), financial viabilities (Bakatjan et al.
2003; Wibowo 2004), procurement (Ng et al. 2007; Ye and Tiong
2003), critical success factors (Osei-Kyei and Chan 2017), USPs
motivations (Osei-Kyei et al. 2018b).
Another major area for the past decades catching the attention
from researchers is unsolicited PPP proposals. Specifically,
researchers’interest in unsolicited PPP proposals continue
unabated as PPP market keeps growing and maturing in other
jurisdictions and sectors (Chan et al. 2010). Surprisingly there is an
increasing trend and enthusiasm about the adoption of USP for
PPP projects in developing countries like Brazil, Ghana and Peru
(Public–Private Infrastructure Advisory Facility (PPIAF) 2009,
Public–Private Infrastructure Advisory Facility (PPIAF) 2014)how-
ever these countries have no commensurate attention for review
and analysis on evaluation criteria for unsolicited PPP proposals.
Going forward, it has become crucial for practitioners to devise
strategic mechanisms to properly manage USPs. The critical strat-
egy suggested by past studies is to formulate a well-defined set of
criteria that could be used to thoroughly evaluate the soundness
and appropriateness of USPs prior to their implementations
(Hodges and Dellacha 2007; Public–Private Infrastructure Advisory
Facility (PPIAF) 2012,2014; World Bank Group and PPIAF
2017b;Osei-Kyeietal.2018b). In fact, creating a clear set of evalu-
ation criteria for unsolicited PPP proposals is believed to enable
public departments/agencies to identify and select proposals that
areinlinewithpublicinterests(Public–Private Infrastructure
Advisory Facility (PPIAF) 2014; Australian Capital Territory
Government (ACT) 2016). In essence, the paper’s aim is to provide
detailed list of key criteria that policy-makers and corporate bodies
need to consider in enhancing the economic and social benefits of
USPs. In this regard, the following objectives were derived: to
ascertain the trends of annual publications on criteria for evaluat-
ing unsolicited PPP proposals from 2004 to 2018; to determine the
author’s contributions to papers on evaluation criteria for unsoli-
cited PPP proposals; to determine the trend of evaluation criteria
identified annually in papers for unsolicited PPP proposals from
2004 to 2018 and finally to establish a set of checklist of evaluation
criteria for unsolicited PPP proposals. The checklist of evaluation
criteria will serve as a foundation for the formulation of relevant
hypotheses for future in-depth empirical investigations.
Background of unsolicited PPP proposals
Significant proportion of PPP investments procured in develop-
ing countries has been unsolicited (Public–Private Infrastructure
Advisory Facility (PPIAF) 2014; World Bank Group and PPIAF
2017c). Public-Private Partnerships (PPP) for private delivery of
public infrastructure projects are traditionally publicly initiated
(World Bank Group and PPIAF 2017b,2017c). Many select
CONTACT Julius Jubilee Nyagormey jubileejulius@yahoo.com;seyramjay@gmail.com
ß2020 Informa UK Limited, trading as Taylor & Francis Group
INTERNATIONAL JOURNAL OF CONSTRUCTION MANAGEMENT
https://doi.org/10.1080/15623599.2020.1783596
projects arising from unsolicited proposals as have been con-
firmed explicitly in literature include; Crown Sydney Resort at
Barangaroo, NorthConnex, the partial lease of Ausgrid, Sydney
Metro Martin Place Station, West Gate Tunnel project, Port
Philip Ferries, Adelaide Creative Industries Precinc (Angus 2017;
Chew 2015); Cranbourne Pakenham sub urban rail line and
CityLink Tullmarine (Chew 2015). When it comes to infrastruc-
ture projects, “unsolicited proposals”(USPs) represent an alter-
native to the traditional project initiation method where the
private sector, rather than the government, takes the leading role
in identifying and developing a project (Public–Private
Infrastructure Advisory Facility (PPIAF) 2014; World Bank
Group and PPIAF 2017b,2017c). This is to say in practice, PPP
projects are procured through two major approaches: solicited
and unsolicited (Hodges 2003; Public–Private Infrastructure
Advisory Facility (PPIAF) 2014; Zawawi et al. 2016).
USP is a privately initiated proposal submitted to the public
sector, without an explicit request from the government to do so
or without any open invitation (Abdel Aziz and Nabavi 2014;
Zawawi et al. 2016; World Bank Group and PPIAF 2017c). Only a
private party can make this proposal to undertake a PPP project,
with no request from the public procurement agencies (United
Nations Commission on International Trade Law (UNCITRAL)
2001). For reasons, governments adopt USPs mainly for rapid
delivery of projects, avoid lengthy competitive tendering process,
lack of public sector capacity to identify and prioritize projects,
ensure quick access to private sector finance and lack of private
investors’interest in projects at inaccessible areas (Osei-Kyei et al.
2018a,2018b; Public–Private Infrastructure Advisory Facility
(PPIAF) 2014;HodgesandDellacha2007).
Unsolicited proposals are not without controversy (Chew
2015). Some of the identified setbacks include absence of best
value for money; lack of fairness, allegation of corruption, abuse
of power, strong public and political opposition, lower level of
economic and societal benefits, lack of transparency and com-
petitive tendering process (Hodges 2003; Hodges and Dellacha
2007; Public–Private Infrastructure Advisory Facility (PPIAF)
2009; Public–Private Infrastructure Advisory Facility (PPIAF)
2014; Osei-Kyei et al. 2018b) particularly if the government
chooses to negotiate USPs directly with the project proponent. It
also comes with the risk of diverting scarce financial resources to
non-priority projects (Hodges and Dellacha 2007; Public–Private
Infrastructure Advisory Facility (PPIAF) 2014). The approach of
direct negotiation or sole sourcing with the USP proponent is
often tainted with allegations of corruption, nepotism, risk mis-
allocation and poor economic and social benefits (Abdel Aziz
and Nabavi 2014; Zawawi et al. 2016). Against these drawbacks
submission of unsolicited PPPs has been on the rise in the recent
past, particularly in some countries like Philippines, Brazil,
Argentina and Chile (Public–Private Infrastructure Advisory
Facility (PPIAF) 2014; World Bank Group and PPIAF 2017b).
Review of literature on criteria for evaluating
unsolicited PPP proposals
Evaluation criteria may vary among jurisdictions, it is therefore,
vital to generate evaluation criteria particularly for developing
economies, where the adoption of unsolicited PPPs is happening
at a rapid pace (Hodges 2003). Abdel Aziz and Nabavi (2011)
reviewed the acts of 29 PPP-enabled states and concluded that
most states did not have sufficiently well-developed evaluation
criteria for managing unsolicited proposals. Suggestive that for
effective management of unsolicited PPPs the public agency
needs to conduct an in-depth assessment within a well-defined
set of criteria (Australian Capital Territory Government (ACT)
2016; World Bank Group and PPIAF 2017c). For best practice
internationally, Public–Private Infrastructure Advisory Facility
(PPIAF) (2012) stipulates that unsolicited proposals are to be
thoroughly evaluated. This is to enable public departments/agen-
cies to identify and select proposals that are in line with public
interests (Public–Private Infrastructure Advisory Facility (PPIAF)
2014; Australian Capital Territory Government (ACT) 2016).
Many studies have attempted identifying different set of crite-
ria for evaluating unsolicited PPP proposals. Among the evaluat-
ing criteria emphasized as important is appropriateness of
risk sharing mechanism, Conformity of proposal with national/
sector policy (Hodges and Dellacha 2007;Public–Private
Infrastructure Advisory Facility (PPIAF) 2009,Public–Private
Infrastructure Advisory Facility (PPIAF) 2012,
Public–Private Infrastructure Advisory Facility (PPIAF) 2014;
Yun et al. 2015; Australian Capital Territory Government (ACT)
2016). World Bank Group and PPIAF (2017b) confirmed that
proposals submitted by investors must be in line with govern-
ment’s development objectives and agenda. In this way, unsoli-
cited PPPs will not only meet the core economic and societal
needs of the host country, but they will also ensure value for
money. Ease of proposal implementation (Hodges and Dellacha
2007) and Whole life value for money (Public–Private
Infrastructure Advisory Facility (PPIAF) 2012;Zhang2005;Yun
et al. 2015; Australian Capital Territory Government (ACT)
2016). World Bank Group and PPIAF (2017b), Public–Private
Infrastructure Advisory Facility (PPIAF) (2012) and Zhang
(2005) have emphasized that USPs should be subjected to crit-
ical selection criteria. (i.e.,) whole lifecycle value for money and
affordability of user tariffs. USPs proponents should provide a
user fee which is reasonable, could easily be afforded by local
and general public without generating excessive profits (Zhang
2005;Public–Private Infrastructure Advisory Facility (PPIAF)
2012; World Bank Group and PPIAF (2017c). More importantly,
the proposed user tariff should be in line with the general pub-
lic’s willingness to pay.
According to Public–Private Infrastructure Advisory Facility
(PPIAF) (2009) financial capabilities of private sector proponent
is essential. The private proponent should demonstrate to having
a strong financial strength and abilities to undertake the pro-
posed project (Public–Private Infrastructure Advisory Facility
(PPIAF) 2012). In their arguments, the proponent should pro-
vide adequate assurances of financing including presenting a
detailed financial plan and methods of raising funds (Australian
Capital Territory Government (ACT) 2016; Public–Private
Infrastructure Advisory Facility (PPIAF) 2009; World Bank
Group and PPIAF 2017b).
Hodges (2003) identified outstanding creativity and innovative
technological solutions as one of the criteria. Government’s
adoption of unsolicited PPPs is to be able to tap into the unique
creativity and innovation of the private sector (Osei-Kyei et al.
2017b). Proposed USPs and technological solutions should be
unique, novel, viable and technically sound and should not
already be in existence (Hodges 2003; Public–Private
Infrastructure Advisory Facility (PPIAF) 2009; World Bank
Group and PPIAF 2017b,2017c). The proponent should demon-
strate strong cohesiveness by presenting tangible evidence that all
participants in the consortium are working in a cohesive
approach (Zhang 2005; World Bank Group and PPIAF 2017c).
Public departments/agencies should assess that participants in
2 J. J. NYAGORMEY ET AL.
the proponent’s consortium have a cordial and cohesive working
relationship (Zhang 2005).
Further, Unsolicited projects should be subjected to sustain-
ability impacts and climate change issues. The proposed solu-
tions should consider climate change issues and meet the
sustainability performance of host country (World Bank Group
and PPIAF 2017b). Environmental safety should also be consid-
ered when evaluating unsolicited PPP proposals (World Bank
Group and PPIAF 2017c). Environmental safety of proposed pro-
ject should have solutions which are environmentally friendly,
conform to the host country’s environmental policies (World
Bank Group and PPIAF 2017c); and should be without any
adverse health effect on occupants and the society
(Public–Private Infrastructure Advisory Facility (PPIAF) 2009;
World Bank Group and PPIAF 2017b). It is observed, from the
above review, that many different criteria could be used to evalu-
ate the suitability and soundness of unsolicited PPP proposals.
Research methodology
Published papers in scientific refereed journals represent import-
ant knowledge resources and a significant way to developing new
areas of research (Al-Sharif and Kaka 2004). PPP related litera-
tures on criteria for evaluating unsolicited projects published
from 2004 to 2018 were retrieved via an approach used by previ-
ous researchers (Ke et al. 2009; Yi and Wang 2013; Yi and Chan
2014; Darko and Chan 2016). The framework of the search
methodology was divided into three-stages as illustrated in
Figure 1.
Noted that Scopus search engine and other research databases
have been used in similar search to conduct thorough reviews in
varying construction management fields (Hong and Chan 2014;
Hong et al. 2012; Ke et al. 2009; Yi and Wang 2013; Yuan and
Shen 2011; Darko and Chan (2016). This study began with the
selection of suitable search engines and keywords, followed by
the selection of papers and journals, the classification of papers
into related categories, then a critical analysis of the papers to
identify the criteria. The various stages of the research method-
ology are explained in detail in the following subsections.
(ii) the journal papers should also have touched on evaluation
criteria used to select USPs.
Identification of published papers
A comprehensive desktop search on the subject area was carried
out under the ‘title/abstract/keyword’. The search keywords
include ‘Unsolicited Proposals’,‘Solicited proposals’‘PPP’and
‘Unsolicited proposals evaluation criteria. Scopus and google
scholar were the principal search engines used. Scopus was the
main with google scholar as the minor respectively. The other
supplementary research databases used include, ResearchGate,
ScienceDirect (Elsevier), Emerald Insight, Taylor and Francis
Group. The keywords were entered into search engines one after
the other and list of relevant papers reflecting the keywords were
obtained. Scopus was widely used to conduct similar reviews on
a variety of topics in literature. This Scopus was chosen for this
study because it covers most publication databases in different
Figure 1. Research framework for the study (adapted from Ke et al. (2009); Yi and Wang (2013) and Yi and Chan (2014). Note: T/A/K - title/abstract/keywords.
INTERNATIONAL JOURNAL OF CONSTRUCTION MANAGEMENT 3
research areas such as engineering, business, management, and
accounting (Hong and Chan 2014).
Selection of papers and journals
In all, 72 publications were retrieved from 33 journals. An in-
depth examination through visual approach was conducted to
sort the papers related to Unsolicited Proposals in PPPs infra-
structure procurement and finally into the journals in which
they were published. Due to the large number of papers
retrieved, a set of criteria was stipulated to trim the number of
papers needed for further analysis. As a result, the journals
selected in this research project had to meet either or all of the
criteria listed as follows:
The journal contains a significant number of papers in the
initial search. Hong et al. (2012) set the benchmark in their
review on partnering research as exceeding 1%of the total
papers and this present study adopted 1%of the total papers
as the benchmark.
The journal was ranked within the top six in the quality rat-
ing conducted by Chau (1997). Chau’s ranking was used
because it is widely accepted by researchers in the construc-
tion management domain.
The paper should establish at least two criteria for evaluat-
ing USPs in PPPs engagements.
Each one of these criteria are normally used in most con-
struction management review research (Darko and Chan 2016;
Hong et al. 2012). The summary of papers retrieved on
Unsolicited PPP proposals in selected journals or publishers
from 2004 to 2018 (both years inclusive) is presented in Table 1.
Finally, as shown in Table 1, Journal of Construction
Engineering and Management (JCEM), Built Environment
Project and Asset Management (BEPAM), Construction
Management and Economics (CME), Journal of Management in
Engineering (JME), Journal of Civil Engineering and
Management (JCEM) were selected based on criterion two and
three. Journal of Facilities Management (JFM), World Bank pub-
lications or PPIAF, Australian Capital Territory publication and
North South Wales (NSW) Parliamentary Research Service were
also selected based on criteria one and three, due to their high
number of papers touching on criteria for evaluating unsolicited
PPP proposals.
The initial papers that did not satisfy any one of the criteria
were discarded. At this stage a total of 26 papers were aban-
doned, due to their irrelevance to the current research. After fil-
tering, a total of 46 papers formed the basis of the review. These
46 identified papers stand in a better position to provide an in-
depth understanding of the current status and present knowledge
gap for further studies as it relates positively with past similar
reviews presented in construction management literature. A lit-
erature review presented by Osei-Kyei and Chan (2015) used 27
papers, Yu et al. (2018) used 26 papers, Owusu et al. (2019) also
used 37 papers to present a review and for another review,
Dwaikat and Ali (2016) used 17 papers. More importantly, the
small sample size of 46 could be attributed to the fact that USPs
related publications are limited. The number although very small,
it can be considered satisfactory and reasonable to draw mean-
ingful conclusions. Thus, the 46 papers could provide know-
ledgeable information on USPs evaluation criteria.
Table 1. Search results of scientific papers on USPs evaluation criteria for PPP procurement.
Names of Journals/Publishers
Papers retrieved from
search engines
Relevant Papers on USPs
criteria for this study
World Bank publications /(PPIAF) 11 9
Built Environment Project and Asset Management (BEPAM) 6 3
Journal of Construction Engineering and Management (JCEM) 5 4
Construction Management and Economics (CME) 5 1
Australian Capital Territory publication (ACT) 4 4
International Journal of Project Management (IJPM) 4 1
NSW Parliamentary Research Service 4 4
Journal of Management in Engineering (JME) 3 2
Journal of Financial Management of Property and Construction (JFMPC) 3 1
Journal of Business Ethics 21
Journal of Facilities Management (JFM) 2 2
Journal of Civil Engineering and Management (JCEM) 2 2
Construction Research Congress 1 1
International Journal of Construction Management (IJCM) 1 1
International Journal of Sustainable Development (IJSD) 1 1
Environmental Impact Assessment Review 1 –
Journal of Environmental Planning and Management (JEPM) 1 1
Government and Policy 11
Energy Policy 11
International Journal of Water Resources Development 1 –
Automation in Construction 1 –
General Assembly of the Commonwealth of Pennsylvania 1 1
Corrs Chambers Westgarth, publications 1 1
International Institute for Sustainable Development 1 1
Journal of Comparative Policy Analysis: Research and Practice 1 1
Engineering, Construction and Architectural Management (ECAM) 1 –
Journal of Construction Engineering and Project management (JCEPM) 1 –
Journal of Public Procurement 1 –
European Planning Studies 1 –
Crown Agent 1 –
Department of Treasury and Finance 1 1
National Energy Technology Laboratory (NETL) 1 1
European Procurement Public Private Partnership Law Review (EPPPL) 1 1
Total 72 46
4 J. J. NYAGORMEY ET AL.
Examining target papers related to USPs evaluation criteria
The research process adopted for this study centered on content
analysis. As stated previously in section 4.2, each of the 46 iden-
tified papers was subjected to thorough examinations via content
analysis considering the criteria for evaluating unsolicited PPPs
proposals. According to Kolbe and Burnett (1991), content ana-
lysis is an effective observational research method to systematic-
ally evaluate the symbolic content of all forms of recorded
communications. Fellows and Liu (2008) pointed out that con-
tent analysis is frequently used to determine the major facets of
a set of data by simply counting the number of times that an
activity happens or a topic is depicted. Both qualitative and
quantitative content analysis methods are employed in this study.
According to Fellows and Liu (2008), in qualitative content ana-
lysis, the emphasis is on determining the meaning of the data
(i.e., grouping the data into categories), whereas quantitative
content analysis extends this to generate numerical values of the
categorized data, such as frequencies, ratings, and rankings, for
further statistical analysis. Therefore, a comparison can be made
and hierarchies of categories can be examined. As to qualitative
content analysis, this study focused on the identification of crite-
ria for assessing unsolicited proposals in the 46 qualified papers.
While quantitative content analysis is based on the qualitative
results to statistically categorize and count the identified criteria.
This approach was employed to conduct a content analysis of
the critical criteria for evaluating unsolicited public–private part-
nerships proposals.
Status and credibility of selected papers
To determine the status and the credibility of information in the
selected papers on the USPs evaluation criteria, all the 46 papers
were subjected to thorough examinations. As presented in the
Table 2, a total of 25 papers out of the 46 representing 54% were
peer reviewed journals papers written by experts and were
reviewed by several other experts in the field before the article
was published in the journal in order to ensure the article’s qual-
ity. The rest were published technical papers, reports and policy
guides written by institutions, organizations and agencies which
were non-peer reviewed.
Research contribution of authors
To determine authors’contributions, a quantitative method pro-
posed by Howard et al. (1987) was adopted. They produced a
formula for calculating contributions of authors to a multi-
authored paper. Earlier, contributions of each writer in a multi-
authored paper is indiscriminately the same as if the paper is
written by a single writer. So, in order to reflect the actual and a
more accurate contribution of individual writers in a multi-auth-
ored paper, this formula was produced based on assumption that
the actual contribution of an author to a multi authored paper
varies and that the first author contributes more than the second
author and the second more than the third and so on (Howard
et al. 1987).
The research contribution from each researcher was analyzed
and ranked quantitatively in a similar fashion as Al-Sharif and
Kaka (2004) did. Tsai and Wen (2005) also adopted this formula
to differentiate the contribution of each individual writer in a
multi-authored paper to identify the research trend of science
education. Again, used in other literature review studies for
ranking contributions of authors to a multi authored paper (Ke
et al. 2009; Yi and Wang 2013). The formula is therefore given
as:
Score ¼1:5ni
Pn
i¼11:5ni
where n ¼number of writers of the paper and i ¼order of the
writers. It should be noted that the order of authorship may not
always reflect the actual contribution difference. Thus, this study
considered both the contribution score and the number of times
that the writer’s name occurred. Applying the formula each pub-
lication was given one score point irrespective of the number of
authors. The one point is therefore divided into corresponding
parts for each author using the formula. A detailed score matrix
distribution for authors is presented in Table 3 based on
the formula.
Chronology of annual publications on unsolicited PPP
proposals in journals
In order to know the development status of researches on unsoli-
cited PPP proposals for the period 2004 to 2018 October, all
the finally selected papers were categorized on yearly basis (see
Table 4) with their corresponding number of researchers.
The total number of papers published was 46, written by a
total of 69 active authors who collaborated from 2004 to 2018.
Analysis and discussion of results
The results presented in this paper cover exclusively publications
obtained from the sampling approach discussed in the “Research
Methodology”section. This clearly puts a great emphasis on the
Table 2. Peer reviewed papers verse non-peer reviewed papers on evaluation criteria.
Credibility of Selected Papers Papers on USPs evaluation criteria Total
Peer Reviewed Papers {1,3,4,5,6,7,8,9,10,11,13,15,16,17,18,24,29,30,31,32,33,35,40,41,46}25
Non-Peer Reviewed Papers {2,12,14,19,20,21,22,23,25,26,27,28,34,35,37,38,39,42,43,44,45}21
Table 3. Score matrix for multi-author papers.
Number of writers
Order of specific writer
12345
1 1.00
2 0.60 0.40
3 0.47 0.32 0.21
4 0.42 0.28 0.18 0.12
5 0.38 0.26 0.17 0.11 0.08
INTERNATIONAL JOURNAL OF CONSTRUCTION MANAGEMENT 5
findings when interpreting the results. The following subsections
capture the annual publication trend, various countries contribu-
tions, institutions and authors contributions, as well as the USPs
evaluation criteria for PPPs.
Annual publications on unsolicited PPP proposals from 2004
to 2018
Figure 2 depicts the annual distribution of related papers on
evaluation criteria for USPs procurement that were published
between the year of 2004 to 2018. The figure 2 also presented
the number of publications with corresponding number of writ-
ers. Based on the figure, USPs evaluation criteria for PPPs started
to gain popularity in the academic discipline as indicated in ear-
lier research conducted from 2003 (Hodges 2003). All the papers
have touched on criteria that the public agency can use to evalu-
ate proposed USPs via PPP. It is worth noting that the figure
only shows years with publications and the corresponding num-
ber of authors in the selected papers.
The time period between 2004 to 2017 demonstrates an ever-
increasing trend of yearly publications from zero in 2004 to 8
publications in 2017. In fact, the rapid increase in publications
began in 2011, which then steadily progressed to a peak of 8
publications in 2017. Indeed, this indicates the gradual rising of
interest in exploring best ways of dealing with USPs in PPP since
its evolution. In 2011, seven years from 2004 in which Ghana re-
launched its national PPP policy, publications on USPs
evaluation criteria had picked up steadily with 6 number of
researchers collaborating to publish 2 papers and progressed to
reach 8 publications to 11 researchers in 2017. This supported
the fact the concept of USPs in PPP was rejuvenated in the year
2011 and that close to 15 Countries including Australia, South
Korea, have since allowed the use of unsolicited proposals for
PPP implementation (Public–Private Infrastructure Advisory
Facility (PPIAF) 2012,2014; Abdel Aziz and Nabavi 2014; World
Bank Group and PPIAF 2017b). For eight years period from
2011 to 2018, 35 papers have been published touching on USPs
evaluation criteria with 56 authors participating. An indication
of the growing interest among various researchers, institutions,
organizations and agencies to explore the best criteria for evalu-
ating USPs in PPP and maturing of the world’s USPs market
between these years. It must be clearly emphasized that the trend
of increasing research on USPs evaluation criteria for PPPs
would continue as more governments are now embracing and
implementing USPs policy after its success in other jurisdiction
(Chan et al. 2010; World Bank Group and PPIAF 2017b).
Author’s contributions to papers on evaluation criteria for
unsolicited PPP proposals
In determining researchers’contributions to a publication on
USPs evaluation criteria, the score matrix presented in Table 3
was used to arrive at the contributions. The score for each
author either in a multi-authored or sole authored publication
was accumulated respectively. For instance, Osei-Kyei, Chan,
Dansoh, Ofori-Kuragu, and Owusu collaborated to publish a
paper, therefore the score for each author is 0.38, 0.26, 0.17, 0.11
and 0.08 respectively hence in measuring the author’s contribu-
tion scores obtained in the various papers in which the author
collaborated within 2004 to 2018 were summed up and subse-
quently awarded to the researcher in question. A similar
approach applies to a sole authored publication. As stated in
Table 4. Search results on annual publications on unsolicited PPP proposals in journals.
Year of Publications 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
No of Papers 0 4 2 3 0 2 0 2 4 4 4 5 4 8 4
No of Researchers 0 8 2 6 0 2 0 6 9 10 9 8 8 11 13
Figure 2. Annual number of publications on USPs evaluation criteria from 2004 to 2018.
6 J. J. NYAGORMEY ET AL.
section 4.6, there were a total of 69 active authors; each collabo-
rated in publishing one or two papers on evaluation criteria for
unsolicited PPP proposals from 2004 to 2018.
Fifteen different authors have a score of at least one point
with one or more papers as presented in Table 5. Eight out of
the fifteen authors are either international organizations or insti-
tutions. Three (3) of such; World Bank Group, IBRD and PPIAF
are international institutions; whiles the three; ACT government,
NSW government and Government of Tasmania are states in
Australia and Depart of Energy US as an agency; an indication
of great interest in the area of and why these investigators con-
tinuously call for finding proper management procedures of
unsolicited PPP proposals to maximize social benefits and reduce
the negative public perception of unsolicited PPP deals
(Public–Private Infrastructure Advisory Facility (PPIAF) 2014;
World Bank Group and PPIAF 2017c).
Eight authors like ACT Government, PPIAF, Zhang X. Q.,
NSW Government, IBRD, Abdel Aziz, A. M., World Bank group,
Andrew, C. and Marques, R. C. with scores of 4.00, 3.00, 3.00,
2.00, 1.80, 1.60, 1.60, 1.60 and 1.32 respectively have the highest
number of research contributions to the exploration of USPs
evaluation criteria in PPP for the past 14 years. Again an affirm-
ation of the huge interest from researchers worldwide to enhance
USPs implementation and practice.
Among the most active authors is the ACT, Government
who published four sole authored technical papers. The second
active contributors are PPIAF and Zhang X. Q. PPIAF multi-
authored five papers with one other author whiles Zhang X. Q
published three sole authored papers with the score point of
three. NSW Government is the third active contributor who
published two sole authored papers each with the score point
of two each. IBRD is the fourth active contributor with 3
papers. Other active contributors are, Abdel Aziz, A. M., World
Bank group, Andrew, C. and Marques, R. C. who collaborated
to multi authored 2, 4, 2 and two papers respectively. It is
observed that even though renowned researchers like Chan,
A.P.C., Osei-Kyei, R. and some other three have contributed to
not less than two number of publications, their individual
researcher’s contributions are very low and this is due to the
large number of researchers contributing to a particular publi-
cation hence the low scores of contributions. In fact, the statis-
tics from Table 8 as shown in Appendix A clearly indicated
how widespread the concept of USPs in PPP has been over the
past 14 years among the earlier researchers from different geo-
graphical regions.
Contributions of countries of origin and institutions to USPs
evaluation criteria research
In determining the country of origin and contribution of institu-
tions, the individual scores of all authors coming from the same
country were computed to obtain an overall score as presented
in Table 6 below. The Table 6 summarizes together the overall
score for each country of origin in addition to the number of
papers produced.The results indicate that Authors from Australia
have higher contributions scores to the USPs evaluation criteria
studies. In overall, Authors in Australia were involved in 11
papers and accumulated an overall score of 10.60. Following in
the descending order, countries that have contributed signifi-
cantly to USPs evaluation criteria researches are USA, Portugal
and Canada; obtained contribution scores of 10.00, 1.32 and 1.00
respectively. Surprisingly, both Australia and USA have 6 num-
ber of Authors however USA has the bulk of 16 publications.
The number of papers published in USA is far more than that of
Australia, however the respective score of papers in Australia is
little more than that of USA. Though same number of Authors
have contributed to publications in USA, however their individ-
ual Author’s contributions are very low and this is due to the
large number of Authors contributing to a particular publication
hence the low scores of contributions.
Criteria identified annually in papers for unsolicited PPP
proposals from 2004 to 2018
Figure 3 displays an Annual Trend of Analysis of evaluation cri-
teria for USPs from 2004 to 2018. Year 2004 recorded zero pub-
lication. A total of fifteen criteria were advanced in 4 selected
publications in 2005 and progressively reached the peak of 21
criteria in 8 papers in 2017. The two papers in 2006 confirmed
10 criteria identified in 2005 and went on to add 5 new criteria.
2007 captured one new criterion in the 3 publications, with the
rest repeating from 2005 and 2006 papers. Twenty set of evalu-
ation criteria were again established in four papers in 2012, out
of which 4 were new, making the overall total criteria stands at
26 since 2004. The statistics clearly shows that before 2012 publi-
cations, 22 criteria were identified in earlier 13 papers that is
within the seven-year period. Out these 22 criteria, 18 were re-
confirmed in four papers in 2012. Exclusively indicative that
these 18 criteria are relevant and important when it comes to the
assessment practice of managing USPs in PPP. From one paper
among the five selected publications in 2015, one new additional
criterion was identified, no other subsequent publications
Table 5. Authors publishing papers on USPs evaluation criteria that scored at least one point.
Name of Author No of Papers Position in Papers
Individual contributions in Papers
Total Score Point12345
ACT Government 4 1 1 1 1 1.00 1.00 1.00 1.00 4.00
PPIAF 5 1 1 1 1 1 0.60 0.60 0.60 0.60 0.60 3.00
Zhang, X.Q. 3 1 1 1 1.00 1.00 1.00 3.00
NSW Government 2 1 1 1.00 1.00 2.00
IBRD 3 2 1 2 0.40 1.00 0.40 1.80
Abdel Aziz, A. M. 2 1 1 0.60 1.00 1.60
World Bank group 4 2 2 2 2 0.40 0.40 0.40 0.40 1.60
Andrew, C. 2 1 1 1.00 0.60 1.60
Marques, R. C. 2 2 1 0.32 1.00 1.32
Joint State Government Commission 1 1 1.00 1.00
Laura, Turley 1 1 1.00 1.00
Lenny, Roth 1 1 1.00 1.00
Angus, Chris (October) 1 1 1.00 1.00
Government of Tasmania 1 1 1.00 1.00
Depart of Energy US 1 1 1.00 1.00
INTERNATIONAL JOURNAL OF CONSTRUCTION MANAGEMENT 7
through to 2018 have highlighted any other new criteria for evaluat-
ing USPs in PPP. Hence the set of criteria outlined in publications
from 2013 to 2018 were all establishing a trend of validation of the
aforementioned criteria identified in literature up to 2015 publica-
tions. A clear indication that some set of criteria have repeatedly
been identified and maintained, a growing institutionalization among
various researches and can be adopted as the leading criteria for
evaluating USPs in PPP in future practice of managing USPs.
Analysis of findings from studies on criteria for unsolicited
PPP project proposals
By means of a comprehensive review, 46 selected publications
were considered for this study. A total of 27 critical criteria for
evaluating unsolicited PPP projects were identified. These
Evaluation criteria (EC) are mainly to ensure consistency and
certainty to the PPP market on how Unsolicited Proposals will
be assessed for consideration and improve sustainable manage-
ment of Unsolicited PPP projects within a transparent frame-
work. The number of times each criterion was identified yearly
by author(s) as have been cited in the literature was presented
and accumulated in Table 7. The accumulation was however
used to rank the criteria identified from 2004 to 2018.
To supplement the analysis of Table 7, a comprehensive sum-
mary of findings from each of the publication on USPs evalu-
ation criteria (EC) was presented in Table 9 as shown in
Appendix B.Table 9 was used to develop Table 7. The full
details of 46 papers with their corresponding numbers, publica-
tion dates, names of authors, number of authors to a paper and
Table 6. Locations of the top Fifteen research Author’s origin.
Name of Author Papers Institutions/University Country Score
ACT Government 4 Australian Capital Territory Australia 4.00
NSW Government 2 NSW Parliamentary Research Service Australia 2.00
Andrew, C. 2 Corrs Chambers Westgarth Australia 1.60
Lenny, Roth 1 NSW Parliamentary Research Service Australia 1.00
Angus, Chris 1 NSW Parliamentary Research Service Australia 1.00
Government of Tasmania 1 Department of Treasury and Finance Australia 1.00
Total 11 10.60
PPIAF 5 World Bank USA 3.00
IBRD 3 World Bank USA 1.80
Abdel Aziz, A. M. 2 University of Washington USA 1.60
World Bank group 4 World Bank USA 1.60
Joint State Government Commission 1 Joint State Government Commission USA 1.00
Depart of Energy US The National Energy Technology Laboratory USA 1.00
1
Total 16 10.00
Marques, R. C. 2 Universidade de Lisbon, Lisbon, Portugal 1.32
Total 2 1.32
Laura, Turley 1 International Institute for Sustainable Development (IISD) Canada 1.00
Total 1 1.00
Figure 3. Annual trend analysis of the evaluation criteria for USPs from 2004 to 2018.
8 J. J. NYAGORMEY ET AL.
the journals or publishers were presented in Table 10 in
Appendix C and used to build Table 9. It is observed from Table
7that USPs are to be assessed against various key criteria.
Acknowledged that these set of USPs evaluation criteria inform
practitioners of the treatment to be considered when accepting
unsolicited PPP proposals and ensure consistency. These most
top ten criteria are Outstanding innovative and unique proposal,
Optimal value for money (positive economic benefits),
Appropriate risk allocation mechanism, Adequate Financial capa-
bilities of proponent (Funding availability), Professional related
experiences and technical capabilities of the proposer, Guarantee
competitive Selection process, Accountable and Transparent
Procurement process, Qualifications of the proposed key person-
nel of the private sector, Negotiable Intellectual property condi-
tions and Affordability by government or user tariffs
Outstanding innovative and unique proposal is one of the
most reported criteria in the literature, representing 52.17%. It is
not surprising that this criterion was identified by 24 different
publications as an important criterion to USPs success. This evi-
dence suggests that outstanding innovative and unique proposal
is a crucial criterion for assessing unsolicited PPP projects. The
objective of PPP is not only to attract private sector finance but
also to benefit from innovative initiatives and advanced technol-
ogy provided by private companies (Osei-Kyei et al. 2014).
Innovation is a meaningful benchmark for local economic and
industrial developments. Through innovative design and con-
struction, private developers and investors can minimize oper-
ational costs, thereby ensuring affordability and reducing
environmental pollution.
Demonstrating optimal value for money (positive economic
benefits) was identified in 22 papers and ranked 2
nd
among the
top ten critical criteria. Procuring unsolicited projects through a
PPP mechanism is to achieve value for money (VFM) (Harris
2004; OECD (Organization for Economic Co-operation and
Development) 2008). Grimsey and Lewis (2005) argue that VFM
is the optimum combination of whole life cycle costs, risks, com-
pletion time and quality in order to meet public requirements.
Value for money is important because the USPs procured under
PPP must reflect public benefits. This finding goes to confirm
the assertion that value for money should be one of the principal
concentrations of governments when considering unsolicited
PPP proposals (Public–Private Infrastructure Advisory Facility
(PPIAF) 2012).
Appropriate risk allocation and sharing. This is also ranked
2nd among the top ten important criteria for assessing USPs in
PPP having been considered one of the fundamental components
of PPP arrangement (Jin and Doloi 2008). It is not surprising
that this criterion was identified by 22 different publications. The
private sector is known to adopt better and more efficient ways
to manage risk than the public sector. This is one reason govern-
ments would want to engage the private sector to share any risks
associated with public projects. Risk allocation involves identify-
ing risks and appropriately sharing it among parties (public and
private sectors) (Ke et al. 2010a,2010b). It must be highlighted
that one unique feature which differentiates PPP from the con-
ventional procurement is the allocation of risk hence a proper
mechanism must be developed to help in allocating risk effect-
ively and efficiently.
Sound Financial capabilities of proponent. Financial capa-
bilities of proponent were identified as the 3rd ranked criteria in
19 different publications on the criteria for evaluating USPs. The
financial strength of proponent is also relevant in assessing the
suitability of unsolicited PPP proposals (World Bank Group and
PPIAF 2017b; Zhang 2005). Financial package usually has a
greater impact on a PPP project’s viability than the physical
design or construction costs (Zhang 2005). This reaffirmed the
position established by Public–Private Infrastructure Advisory
Facility (PPIAF) (2012) that private sector proponent should
demonstrate the financial strength to undertake the proposed
project through PPP arrangement. In addition, the key sources
of finance for the proposed project should also be clear, known
and identifiable.
Competitive Selection process. This criterion is ranked 5
th
top criteria identified in literature and was identified in 16
papers. It is very important that competitive selection process is
adopted to select the most qualified contractor based on the
expertise and experience (Chan et al. 2010). It enhances project
value for money as well. At a minimum, a principle should be
that all unsolicited proposals are channeled into a transparent,
competitive process where challengers have a fair chance of win-
ning the tender.
Accountable and Transparent Procurement process. This
criterion was identified in 15 different papers representing
32.61%. It is ranked 6
th
criterion among the top ten criteria
against which USPs in PPP is assessed for consideration and
approval. It must be highlighted that accountability and transpar-
ency do not only apply to the tendering process but must be
observed throughout the delivery of the unsolicited PPP project.
This is expected because transparency and accountability in PPP
arrangements can reduce the negative perception of the public
on private sector participation in public service delivery and fos-
ter trust and confidence among the public and project partici-
pants (Osei-Kyei and Chan 2016). It is always important to clear
any doubts or rumors within the public domain concerning the
delivery of unsolicited PPP projects, as negative public percep-
tion could affect the successful implementation of projects. All
relevant project information such as public accountability and
transparency in the financing, funding and delivery of public
infrastructure, as well as its future performance should be dis-
closed to mitigate stakeholder concerns and ensure confidence
(World Bank Group and PPIAF 2017b).
Negotiable Intellectual property conditions. The 7
th
criter-
ion among the top ten was Intellectual property conditions with
a percentage score of 30.43%. Legal respect for proprietary right
to techniques and intellectual-property rights are essential to sus-
tainable private sector development as they encourage private
entities to submit innovative USPs. Proponents disclosing all the
information regarding the treatment of intellectual property max-
imizes transparency and also likely to boost the interest from
other potential bidders, strengthen the public agency’s ability to
organize a competitive-tender process with equal bidding condi-
tions (World Bank Group and PPIAF 2017b).
Affordability requirement by government. Affordability
requirement was reported in 13 papers representing 28.26% and
ranked the 8
th
criterion identified in literature. It is not surpris-
ing because it enables the Public Agency to evaluate proposed
project’s implications for government’s support whether it is
affordable to the Government, by examining expected Direct and
Contingent Liabilities, or affordable to the end user, if a user-
pays model is being proposed. It goes to confirm that the
Proposed Project does not require any Government support, or a
description of the type and range of Government support that
the Proposed Project is expected to require (World Bank Group
and PPIAF 2017b). There is a claim that, when the costs of
unsolicited PPP projects are reduced, users are likely to pay
INTERNATIONAL JOURNAL OF CONSTRUCTION MANAGEMENT 9
Table 7. Criteria identified annually in papers for unsolicited PPP proposals from 2004 to 2018.
Year 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Total Percent %
Papers
04230202445448446Code
c2 ͓͓冑͓冑͓冑͓冑͓͓冑͓冑͓冑͓͓ ͓ 冑͓͓ ͓ 冑͓͓ ͓ 冑͓͓ ͓ ͓冑͓͓冑24 52.17
c1 ͓͓冑͓͓冑͓冑͓͓͓͓冑͓͓ ͓ 冑͓͓冑͓͓ ͓ 冑͓冑͓͓ ͓ 冑͓冑22 47.83
c3 ͓冑͓͓冑͓͓ ͓ 冑͓冑͓͓冑͓͓͓͓͓冑͓冑͓͓͓͓͓冑͓͓冑22 47.83
c5 ͓͓
冑͓冑͓冑͓冑͓冑͓冑͓冑͓͓ ͓
冑͓冑͓͓͓͓͓
冑͓͓
冑19 41.3
c11 ͓冑͓冑͓冑͓͓冑͓冑͓͓冑͓͓ ͓ 冑͓͓͓͓͓冑͓͓冑18 39.13
c14 ͓͓ ͓ 冑͓冑͓冑͓冑͓冑͓͓ ͓ 冑͓冑͓͓冑͓͓ ͓冑16 34.78
c12 ͓冑͓͓冑͓冑͓冑͓͓冑͓冑͓͓ ͓ 冑͓͓ ͓冑͓冑15 32.61
c13 ͓冑͓冑͓冑͓冑͓͓
冑͓͓͓͓
冑͓͓͓͓͓
冑15 32.61
c4 ͓冑͓冑͓͓冑͓冑͓冑͓冑͓͓冑͓͓ ͓ 冑͓͓冑14 30.43
c7 ͓冑͓冑͓͓冑͓冑͓͓冑͓冑͓͓ ͓ ͓冑͓冑13 28.26
c6 ͓冑͓冑͓͓冑͓͓ ͓ 冑͓冑͓͓冑͓冑11 23.91
c10 ͓冑͓冑͓冑͓冑͓͓
冑͓冑͓͓
冑͓冑10 21.74
c9 ͓͓冑͓冑͓冑͓冑͓冑͓冑͓冑͓冑919.57
c8 ͓͓冑͓冑͓͓冑͓冑͓冑͓冑817.39
c17 ͓冑͓͓冑͓冑͓冑͓冑͓冑715.22
c15 ͓冑͓冑͓冑͓冑͓͓
冑613.04
c16 ͓冑͓冑͓͓冑͓冑͓冑613.04
c22 ͓冑͓冑͓冑͓͓冑510.87
c18 ͓冑͓冑͓冑͓冑48.70
c20 ͓冑͓冑͓冑͓冑48.70
c21 ͓冑͓冑͓冑͓冑48.70
c26 ͓冑͓冑͓冑͓冑48.70
c19 ͓冑͓͓冑36.52
c24 ͓冑͓冑͓冑36.52
c25 ͓冑͓͓冑36.52
c23 ͓冑͓冑24.35
c27 ͓冑12.17
Total 0 15 11 13 0 12 0 5 20 15 15 15 15 21 11
10 J. J. NYAGORMEY ET AL.
lower tariffs, thereby enhancing the living standards of people,
particularly for low-income earners in society.
Conclusions
Many governments across the world seek for the development of
effective guidelines for managing Unsolicited Proposals in PPPs
to provide a wide variety of net benefits for societies and nations.
PPP related literatures on criteria for evaluating unsolicited proj-
ects published from 2004 to 2018 were retrieved via a three-stage
approach used by previous researchers. Given that all the criteria
are normally seen as critical in the literature, a content analysis
was conducted to determine the major facets of a set of criteria
by simply counting the number of times they occurred in the 46
papers retrieved.
Indeed, this study has provided a profound evidence of asser-
tions that USPs evaluating criteria in PPP is one major area
attracting attention from researchers in PPP studies. The year
2004 recorded zero publication. A total of fifteen criteria were
advanced in 4 selected publications in 2005 and progressively
reached the peak of 21 criteria in 8 papers in 2017. A total of 69
authors have collaborated to publish 46 papers. Authors like
ACT Government, PPIAF, Zhang X. Q., NSW Government,
IBRD, Abdel Aziz, A. M., World Bank group, Marques, R. C.
were among the fifteen most active contributors to publications
that explored the best criteria for evaluating USPs project from
2004 to 2018.
Ten most reported USPs evaluation criteria are outstanding
innovative and unique proposal, optimal value for money (posi-
tive economic benefits), appropriate risk allocation mechanism,
adequate Financial capabilities of proponent (Funding availabil-
ity), Professional related experiences and technical capabilities of
the proposer, guarantee competitive selection process, account-
able and transparent procurement process, intellectual property
conditions, affordability requirement by government or user tar-
iffs and qualifications of the proposed key personnel of the pri-
vate sector.
The findings revealed in this study have provided a solid
foundation for future empirical studies and analysis on USP
evaluation criteria in terms of scope and other related phenom-
enon in PPP. Governments and private sector developers seeking
to enter into privately initiated PPP market would be informed
of the most important critical criteria for evaluating USPs irre-
spective of country, sector and project model.
Acknowledgements
This paper forms part of a PhD research project on Managing
Unsolicited Proposals in Public–Private Partnership Infrastructure
Procurement. The authors acknowledge that this paper shares a
similar background and methodology with other related papers, but
with different scopes and objectives. The research project is under-
taken in the Department of Construction Technology and
Management, at Kwame Nkrumah University of Science and
Technology, Kumasi, Ghana. Finally, the authors are exceedingly
grateful to the editors and anonymous reviewers whose invaluable
comments and suggestions substantially helped in improving the
quality of this paper.
Disclosure statement
No potential conflict of interest was reported by the author(s).
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Appendix A
Table 8. Author’s contributions to papers on evaluation criteria for USPs in PPP.
Name of Author No of Papers Position in Papers
Individual contributions in Papers
Total Score Point12345
ACT Government 4 1 1 1 1 1.00 1.00 1.00 1.00 4.00
PPIAF 5 1 1 1 1 1 0.60 0.60 0.60 0.60 0.60 3.00
Zhang, X.Q. 3 1 1 1 1.00 1.00 1.00 3.00
NSW Government 2 1 1 1.00 1.00 2.00
IBRD 3 2 1 2 0.40 1.00 0.40 1.80
Abdel Aziz, A. M. 2 1 1 0.60 1.00 1.60
World Bank group 4 2 2 2 2 0.40 0.40 0.40 0.40 1.60
Marques, R. C. 2 2 1 0.32 1.00 1.32
Andrew, C. 2 1 1 1.00 0.60 1.60
Joint State Government Commission 1 1 1.00 1.00
Laura, Turley 1 1 1.00 1.00
Lenny, Roth 1 1 1.00 1.00
Angus, Chris (October) 1 1 1.00 1.00
Government of Tasmania 1 1 1.00 1.00
Depart of Energy US 1 1 1.00 1.00
Chan, A.P.C. 3 2 2 2 0.32 0.26 0.26 0.84
Osei-Kyei, R. 2 1 1 0.38 0.38 0.76
Hodges J. 1 1 0.60 0.60
Neves P. 1 1 0.60 0.60
Liu, T. 1 1 0.60 0.60
Muhammad, Z. 1 1 0.60 0.60
Queiroz Cesar 1 1 0.60 0.60
Babatunde, S. O. 1 1 0.47 0.47
Lenferink, S. 1 1 0.47 0.47
Patil, N. A. 1 1 0.47 0.47
Regan, M. 1 1 0.47 0.47
Wang, N. 1 1 0.47 0.47
Martins, A. C. 1 1 0.47 0.47
Salman, A. F. M. 1 1 0.47 0.47
Zawawi M. I. Z. 1 1 0.47 0.47
Cheung, E. 1 1 0.47 0.47
Yun, S. 1 1 0.42 0.42
Mladenovic, G. 1 1 0.42 0.42
Li, B. 1 1 0.42 0.42
Nabavi, H. 1 2 0.40 0.40
Johar, F. 1 2 0.40 0.40
Dellacha G. 1 2 0.40 0.40
Kim D. J 1 2 0.40 0.40
Clarke, Robert 1 2 0.40 0.40
Wilkinson, S. 1 2 0.40 0.40
Dansoh, A., 2 3 3 0.17 0.17 0.34
Opawole, A. 1 2 0.32 0.32
Tillema, T. 1 2 0.32 0.32
Tharun, D. 1 2 0.32 0.32
Smith, J. 1 2 0.32 0.32
Wei, K. 1 2 0.32 0.32
Skibniewski, M. J. 1 2 0.32 0.32
Kulatunga U. 1 2 0.32 0.32
Jung, W. 1 2 0.28 0.28
Vajdic, N. 1 2 0.28 0.28
Akintoye, A. 1 2 0.28 0.28
Ofori-Kuragu, J.K. 2 4 4 0.11 0.11 0.22
Akinsiku, O. E. 1 3 0.21 0.21
Arts, J. 1 3 0.21 0.21
Laishram, B. 1 3 0.21 0.21
Love, P. 1 3 0.21 0.21
Sun, H. 1 3 0.21 0.21
Cruz, C. O. 1 3 0.21 0.21
Basha, I 1 3 0.21 0.21
Thayaparan M. 1 3 0.21 0.21
Kajewski, S. 1 3 0.21 0.21
Han, S. H. 1 3 0.18 0.18
W€
undsch, B. 1 3 0.18 0.18
Edwards, P. J. 1 3 0.18 0.18
Park, H. 1 4 0.12 0.12
Temeljotov-Salaj, A. 1 4 0.12 0.12
Hardcastle, C. 1 4 0.12 0.12
Owusu, K. E. 1 5 0.08 0.08
Oppong G. D. 1 5 0.08 0.08
INTERNATIONAL JOURNAL OF CONSTRUCTION MANAGEMENT 13
Appendix B
Table 9. Findings from studies on evaluation criteria for unsolicited PPP proposals from 2004 to 2018 (year inclusive).
Codes Evaluation criteria for unsolicited PPP proposals Journal Papers Total Percent %
C2 Outstanding innovative and unique proposal {1,2,3,5,7,8,9,10,11,13,17,19,22,
23,25,26,28,36,40,41,43,44,45,46}
24 52.17
C3 Demonstrate optimal value for money (positive economic benefits) {1,2,3,12,16,18,20,22,23,24,25,27,
28,29,33,34,35,41,42,43,44,46}
22 47.83
C1 Appropriate risk allocation mechanism {2,3,4,12,15,18,19,20,21,24,25,27,
30,31,32,33,34,35,36,42,43,46}
22 47.83
C5 Financial capabilities of proponent (Funding availability) {2,4,9,15,19,22,23,24,25,26,27,
29,34,39,40,42,43,45,46}
19 41.3
C11 Professional related experiences and technical capabilities of the proposer {1,3,4,9.23,24,26,27,29,34,
35,39,40,42,43,44,45,46}
18 39.13
C14 Guarantee competitive selection process {1,3,4,15,17,20,22,24,26,
28,30,33,36,38,39,46}
16 34.78
C12 Accountable and transparent procurement process {1,2,4,6,7,13,15,17,20,22,24,25,33,39,41}15 32.61
C13 Qualifications of the proposed key personnel of the private sector {1,3,4,9,23,24,26,34,35,39,42,43,44,45,46}15 32.61
C4 Negotiable Intellectual property conditions {2,3,17,19,25,26,27,28,34,35,39,41,42,43}14 30.43
C7 Affordability by government or user tariffs {16,17,19,20,22,23,25,27,34,35,42,43,46}13 28.26
C6 Aligns with sector/national plan or Strategic goals and objectives {2,3,12,18,20,22,23,25,26,27,44}11 23.91
C10 Profitability of proposed project (Commercial viability/ Return on investment) {4,5,7,9,11,13,17,34,42,43}10 221.74
C9 Support public stakeholders’participation and engagement {3,4,5,8,9,24,27,33,36}9 19.57
C8 Strong private consortium and implementation capabilities {12,15,16,18,24,31,32,36}8 17.39
C17 Ability to address community problems, issues or needs {6,8,9,10,19,34,42}7 15.22
C16 No adverse climate change and air quality impacts {4,7,10,19,22,26}6 13.04
C15 USP Environmental policy and management plan {4,5,9,19,22,23}6 13.04
C22 Clarity of project requirements and procedures {3,18,24,35,39}5 10.87
C18 Operation and maintenance policy {5,6,7,9}4 8.70
C20 Proposal Fit for purpose {2,3,22,25}4 8.70
C21 Contains health and safety solutions {6,7,9,10}4 8.70
C26 Local/community merit of proposal {3,4,17,45}4 8.70
C19 USP involve local policy content {3,14,23}3 6.52
C24 Uses sustainable design and materials {9,10,11}3 6.52
C25 Knowledge and Technology transfer {3,14,23}3 6.52
C23 Cost effective solution or faster to implement {19,23}2 4.35
C27 Clearly defined roles and responsibilities of project participants. {18}1 2.17
14 J. J. NYAGORMEY ET AL.
Appendix C
Table 10. A full details of papers on USPs in PPP from selected journal (2004 to 2018).
No Year Authors/ Writers No. of Contributors Journals/ Publishers USP Y/No
1 2014 Abdel Aziz, A., and Nabavi, H. 2 Construction Research Congress Yes
2 2016 ACT Government 1 Australian Capital Territory publication. Yes
3 2012 Babatunde, S. O., Opawole, A. and Akinsiku, O. E. 3 Journal of Facilities Management Yes
4 2018 Muhammad, Z. and Johar, F. 2 International Journal of Construction Management Yes
5 2013 Lenferink, S., Tillema, T., and Arts, J. 3 International Journal of Project Management Yes
6 2009 Lund-Thomsen, P. 1 Journal of Business Ethics Yes
7 2016 Patil, N. A., Tharun, D., and Laishram, B. 3 Journal of Environmental Planning and Management Yes
8 2011 Regan, M., Smith, J., & Love, P. 3 Government and Policy Yes
9 2005 Zhang, X.Q. 1 Journal of Construction Engineering and Management Yes
10 2014 Wang, N., Wei, K., and Sun, H. 3 Journal of Management in Engineering Yes
11 2011 Martins, A. C., Marques, R. C., & Cruz, C. O. 3 Energy Policy Yes
12 2007 Hodges J. and Dellacha G. 2 PPIAF and World Bank publications Yes
13 2007 Salman, A. F. M., Skibniewski, M. J., & Basha, I 3 Journal of Construction Engineering and Management Yes
14 2017 Neves P. and Kim D. J 2 World Bank Publications Yes
15 2005 Zhang, X.Q. 1 Journal of Construction Engineering and Management Yes
16 2005 Zhang, X.Q. 1 Journal of Construction Engineering and Management. Yes
17 2016 Zawawi M. I. Z., Kulatunga U. and Thayaparan M. 3 Built Environment Project and Asset
Management (BEPAM)
Yes
18 2015 Yun, S., Jung, W., Han, S. H., & Park, H. 4 Journal of Civil Engineering and Management Yes
19 2009 International Bank for Reconstruction and Development
(IBRD) and World Bank
2 World Bank Publications Yes
20 2012 Public-Private Infrastructure Advisory Facility (PPIAF) 2 World Bank Publications Yes
21 2014 PPIAF and World Bank Group 2 World Bank Publications Yes
22 2017b World Bank Group/ PPIAF 2 World Bank Publications Yes
23 2017c World Bank Group/ PPIAF 2 World Bank Publications Yes
24 2007 Abdel Aziz, Ahmed M. 1 Journal of Civil Engineering and Management Yes
25 2015 ACT Government 1 Australian Capital Territory publication. Yes
26 2006 Joint State Government Commission 1 General Assembly of the Commonwealth of
Pennsylvania
Yes
27 2018 ACT Government 1 Australian Capital Territory publication. Yes
28 2014 Andrew, Chew and Clarke, Robert 2 Corrs Chambers Westgarth, publications Yes
29 2015 Laura, Turley 1 International Institute for Sustainable Development Yes
30 2013 Mladenovic, G., Vajdic, N., W€
undsch, B., & Temeljotov-
Salaj, A.
4 BEPAM Yes
31 2013 Liu, T., and Wilkinson, S. 2 BEPAM Yes
32 2012 Cheung, E., Chan, A. P.C., and Kajewski, S. 3 Journal of Facilities Management Yes
33 2017 Marques, R. C. 1 Journal of Comparative Policy Analysis: Research
and Practice
Yes
34 2013 Lenny, Roth 1 NSW Parliamentary Research Service Yes
35 2017 Angus, Chris (October) 1 NSW Parliamentary Research Service Yes
36 2005 Bing Li, A. Akintoye, P. J. Edwards and C. Hardcastle 4 Construction Management and Economics Yes
37 2016 ACT Government 1 Australian Capital Territory publication. Yes
38 2005 Queiroz Cesar, IBRD 2 World Bank publications Yes
39 2017 IBRD 1 World Bank publications Yes
40 2018b Osei-Kyei, R., Chan, A.P.C., Dansoh, A., Ofori-Kuragu, J.K.,
and Owusu, K. E
5 Journal of Financial Management of Property and
Construction JFMPC
Yes
41 2018a Osei-Kyei, R., Chan, A.P.C., Dansoh, A., Ofori-Kuragu, J.K.,
and Oppong G. D.
5 Journal of Management in Engineering Yes
42 2012 NSW Government (august) 1 NSW Parliamentary Research Service Yes
43 2017 NSW Government (August) 1 NSW Parliamentary Research Service Yes
44 2015 Government of Tasmania 1 Department of Treasury and Finance Yes
45 2017 Depart of Energy US 1 National Energy Technology Laboratory (NETL) Yes
46 2015 Andrew, C. 1 European Procurement Public Private Partnership Law
Review (EPPPL)
Yes
INTERNATIONAL JOURNAL OF CONSTRUCTION MANAGEMENT 15
