Systematic literature review on performance drivers of Ph.D. success: utilizing PRISMA, TCCM, and an 8-step approach

Abstract

The study systematically assesses the determinants impacting Ph.D. success, amalgamating insights from 38 meticulously curated studies. Through the integration of PRISMA, TCCM, and an 8-step process, it delineates crucial findings and factors influencing successful Ph.D. completion. The PRISMA diagram intricately outlines the data retrieval process, while the TCCM framework systematically organizes discoveries, emphasizing elements crucial to Ph.D. achievement, including timely completion. Previous studies encompassed 17 theories (T), five essential characteristics (C) or factors, nine distinct countries or contexts (C), and diverse methodologies (M) encompassing qualitative, quantitative, and mixed approaches. Institutional factors emerge as the most prominent within the corpus of 38 studies at 65.79%, followed by demographic, financial, and psychological factors at varying degrees, with social factors contributing minimally at 7.89% to Ph.D. progression. The research meticulously follows an 8-step process throughout its developmental trajectory, underscoring critical determinants impacting Ph.D. candidates’ satisfaction, advancement, and persistence. The study’s limitation lies in including 38 studies based on specific criteria. By consolidating prior works, conducting critical analysis, and comparing findings, it offers insights into factors affecting successful Ph.D. attainment, guiding institutions, policymakers, funders, and Ph.D. students. Additionally, it pioneers the field by advancing methodologies through integrating PRISMA, TCCM framework, and 8-step approaches, paving the way for future research endeavors.

Keywords:

• Ph.D
• success factors
• performance
• PRISMA
• intention to quit
• systematic review
• TCCM
• and 8- steps process

REVIEWING EDITOR:

• Stephen Darwin, Universidad Alberto Hurtado, Chile

SUBJECTS:

• Study Skills
• Adult Education and Lifelong Learning
• Higher Education
• School Psychology
• Education Policy & Politics

1. Introduction

The landscape of doctoral studies is witnessing a significant rise in both the pursuit of Ph.D. qualifications and the discourse surrounding their successful attainment. The escalation in unsuccessful Ph.D. attempts, dropout instances, and prolonged completion durations has catalyzed extensive debates regarding the future trajectory of emerging scholars. This study aims to systematically evaluate the expanding corpus of literature delineating the pivotal factors driving Ph.D. success.

Within and outside academia, if we think positively, surviving the rigorous ‘career competition’ appears notably more achievable, particularly for Ph.D. holders when compared to other individuals (Skopek et al., 2022, p. 318). This is because Ph.D. students undergo a structured training program and are referred to as new scientific community members (Lee & Boud, 2003) and discipline stewards (Golde & Walker, 2006). The conventional passive view turns into tension when the statistics report that many Ph.D. students start their Ph.D. journey but do not survive in the race. Jones (2013) claims that the attrition rate for Ph.D. programs ranges from 33% to 70%, though McCray and Joseph-Richard (2020) mention that this rate is 40%–50%. Castelló et al. (2017) identified that one-third of Ph.D. students who are still enrolled wished to be excluded at some point in their program.

The seriousness of the discussion surrounding investment in research and development is evident in the Lisbon Agenda, which aims to invest 3% of gross national income in research and development (European Commission, 2003; Keeling, 2006). With this agenda, most petite European countries agreed to invest (van der Haert et al., 2014). This scenario is caused by the emerging debate influenced by the quality of Ph.D. education and the development of future researchers (McAlpine et al., 2020). Investment in research and development is a priority for many universities and regions, as it can lead to mutual benefits in regional social and economic development (OECD, 2008). Therefore, it is essential to identify the factors contributing to Ph.D. success and failure to improve the investment in research and support Ph.D. candidates in achieving their goals.

Defining a successful Ph.D. has been a subject of discourse across disciplines. It encompasses more than thesis production, extending to personal and professional development (Park, 2005; Hughes & Tight, 2013). While timely completion is recognized as a significant success marker (Ward & Brennan, 2020), various perspectives emphasize academic achievements, career success, or publications as markers of success (Canal-Domínguez & Wall, 2014; De Vogel, 2022; Kiley, 2017).

The significance of completing a Ph.D. promptly cannot be overstated, as delays or non-completion can have far-reaching implications for both the individuals involved and their respective institutions. Van de Schoot et al. (2013) have demonstrated that this phenomenon places considerable pressure on Ph.D. students and their supervisors, resulting in a loss of valuable time and resources invested in their mutual growth. Potential stakeholders such as academic institutions, funders, organizers, and doctoral program supervisors must implement well-developed policies and practices to address this issue. However, the effectiveness of these measures is contingent upon the availability of accurate baseline data, as emphasized by Bourke et al. (2004) and Groenvynck et al. (2013).

Further, tracking the percentage of successful Ph.D. candidates has emerged as a vital tool for monitoring the ebb and flow of researchers in the academic labor market. This metric also serves as an indicator of the efficiency and effectiveness of Ph.D. education, as evidenced by studies conducted by Larivière (2012), Robertson (2017), Visser et al. (2007), and Wright and Cochrane (2000). Consequently, key stakeholders such as policymakers and educational institutions have a vested interest in closely monitoring the participation rates of Ph.D. students in this dynamic labor market, as highlighted by Bao et al. (2018).

This systematic collection of 38 studies has presented diverse data and views regarding the factors contributing to Ph.D. success. These discussions are limited to repeatedly commenting on the same factors. For example, demographic characteristics, such as age (Robertson, 2017), gender (Castelló et al., 2017), nationality (Groenvynck et al., 2013); institutional factors, such as discipline (Humphrey et al., 2012), supervisor and students’ duo (Holzweiss, 2022; Jara, 2021), psychological factors, such as 'Imposterism’ (Tao & Gloria, 2019), social factors, like, family (Kluever, 1997), colleagues (Spaulding & Rockinson-Szapkiw, 2012) impacting the flow of Ph.D. success. Similarly, appointment type and finance source, like funding (Visser et al., 2007), correlate positively and negatively with a successful Ph.D. The existing literature shows complex dynamics in Ph.D. students’ lives, proving challenges to program completion and future career success. All this selective attention to previous literary works prompts the goal of this study to comprehensively synthesize a systematic summary of existing knowledge by asking: How, why, and what factors drive Ph.D. success?

Before undertaking the current systematic literature review, we assessed the prevailing standards in systematic literature reviews related to Ph. D. in recent years. In this regard, we examined a selection of recently published SLRs in 2022 to gain insights into the current landscape. Huet and Casanova (2022) underscored the existence of a trade-off between the progress of Ph.D. students and their supervisors’ professionalism, highlighting this association’s significance in fostering meaningful experiences. Their SLR specifically delved into the topic of professional development and the performance of Ph.D. supervisors. Meanwhile, Francis et al. (2022) tackled the issue of race in doctoral admissions through their SLR, although their study focused on the context of the United States. Their work sheds light on this matter’s complexities within the Ph.D. domain. Similarly, Jackman et al. (2022) expressed concerns about the poor mental health of Ph.D. students, with their SLR primarily prioritizing early-stage students. Their findings shed light on the specific challenges faced by this particular group and underscore the need for targeted support. Turning to the role of educational institutions in nurturing Ph.D. students’ writing abilities, Calle-Arango and Ávila Reyes (2022) conducted an SLR that delves into this subject throughout their study. Their work elucidates the importance of educational institutions in fostering practical writing skills among Ph.D. students. Lastly, Cardoso et al. (2022) culminate their study with an analysis of the transformation of doctoral studies over time. Examining 29 systematic studies encompassing various aspects such as foundations, objectives, methods, skills, organization, and processes provides valuable insights into the evolving nature of doctoral programs. Reviewing these recent SLRs, we have comprehensively understood the current research landscape and identified critical focus areas within the Ph.D. domain.

This study’s systematic literature review (SLR) contributes significantly to scholarly discussions by employing a progressive methodology. A qualitative approach was initially adopted, utilizing a PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) diagram to streamline the data retrieval process. This rigorous process yielded an initial pool of 175 relevant studies, from which a final selection of 38 studies with prospective insights was identified. Subsequently, the study applied the TCCM (theory, context, characteristics, and method) framework to establish connections between various complex relationships and Ph.D. success. This comprehensive framework encompasses positive and negative factors, highlighting the importance of drawing insights from individual studies. Furthermore, the study explores strategies and proposes future research directions, ensuring a holistic examination of the subject matter. Throughout this process, the SLR adhered to the 8-step methodology for conducting systematic literature reviews, ensuring a thorough and rigorous analysis. Adopting these exact steps and frameworks enhances the credibility and reliability of the study and contributes to advancing knowledge in the field.

The development of the study is structured as a report aiming to contribute to the understanding of students, universities, and the public sector by clarifying the factors of Ph.D. success and areas for improvement. As a result, concerned stakeholders can implement the findings before calling for a Ph.D. program plan, ensuring an accurate road map for Ph.D. students. Overall, the study’s contribution will advance the scholarly discussion on Ph.D. success and remind us of the urgency of a successful Ph.D.

The remainder of the study is as follows: Section 2 describes the literature retrieval process. Then, Section 3- reports all the results of the previously discussed factors. It also highlights (the theories, contexts, and methodologies) that underpin this factor representation. Finally, in Section 4, we conclude a discussion outlining potential areas for future research.

2. The process of literature review

The study meticulously gathered and scrutinized the existing literature about Ph.D. success. The aim was to identify research gaps through systematic literature reviews and present critical premises on previous literature using transparent, rigorous, and reproducible methods (Paul & Criado, 2020; Snyder, 2019). Furthermore, as a scientific investigation, this process needs validation, reliability, and repeatability (Xiao & Watson, 2019). Therefore, at the beginning of the study, for confirmation of protocol and reporting, we followed (Xiao & Watson, 2019, p. 103) recommended guidelines (Figure 1).

Figure 1. The 8-step process of doing a systematic literature review (Xiao & Watson, 2019).

A specified set of search terms determined to trace relevant studies. Despite the extensive discussion on Ph.D. and doctoral education, finding worthy studies and avoiding junk took much work. We did a quick trial search on Google Scholar with the words ‘Ph.D. or Doctorial,’ ‘education,’ and ‘success’ and found a large number of studies. Figure 2 shows the keyword co-occurrence that we perform with VOS viewer software. Keyword co-occurrence analysis essentially identifies emerging research themes in a specific domain and includes more areas to search for keywords (Kevork & Vrechopoulos, 2009). In Figure 2, the bold letters keywords are the main keyword, which has different keywords, signifying significant keywords used in the prior studies.

We got 5 clusters with 40 items of keywords. Following phrases, related terms, acronyms, spelling variations, and synonyms, we organize our work to meet search demand. Using Boolean, our final work initially turns into 12 keywords, ((((‘Ph.D.’ OR ‘doctoral’ OR ‘doctorate’) AND (‘study’ OR ‘studies’ OR ‘education’ OR ‘training’ OR ‘dissertation’)) AND (‘complete’ OR ‘completion’ OR ‘success’ OR ‘successful’))), as a result, Scopus provides 576 studies and Web of Science 538 studies. We must note that we only use these two databases to collect studies. We customized our search from 2000 to 2022 because the collected studies already cover the preceding works of 2000. We determined that this timeline was enough to fulfill our purpose (Rowley & Slack, 2004). The offered guidelines help us complete this whole process.

Figure 2. The keyword occurrence analysis using the VOS viewer software.

Throughout this process, we organized 1114 studies systematically to perform our research. After removing duplicates, eligibility and assessing titles and abstracts, we have 38 studies to gain knowledge. We control the quality assessment through journal ranking (ABS- 1,2,3 and ABCD- A & B only).

2.1. The preceding studies’ inclusion

The search strategy advances to the inclusion criteria phase, which is crucial for categorizing studies and ensuring interpretability and manageability within the literature review (Xiao & Watson, 2019). These criteria prioritize open-access, peer-reviewed scholarly studies focusing on Ph.D. students’ success and failure factors, emphasizing global perspectives and employing quantitative and qualitative analyses. Additionally, inclusion extends beyond students to encompass various Ph.D.-related stakeholders, excluding conference articles, book chapters, dissertations, theses, and non-English studies. This process yielded a final dataset of 38 relevant studies, offering multifaceted perspectives on Ph.D.-related issues, including performance management, socio-economic impact, psychological aspects, challenges, and Ph.D. students’ future career participation. The adoption of the Prisma framework streamlined data retrieval and affirmed process validity (Figure 3).

Figure 3. The data retrieval process through PRISMA (http://prisma-statement.org/, 2023).

3. Reporting the findings

The review starts with a research question: How, why, and what factors drive Ph.D. success? We employed the (Paul & Rosado-Serrano, 2019) TCCM (Theory, characteristics, context, methodology) framework to structure the research answer. This framework ensures the robustness of SLR and offers a valid, transparent opinion (Billore & Anisimova, 2021). The basic premise of the research answer lies in the second element of TCCM: characteristic or factor. Although our research question is one, we have answered it in three stages. First, we collectively figure out what characteristics are driving a successful Ph.D. Then, how are they driving a successful Ph.D.? And finally, why are they driving a successful Ph.D.? To ensure more profound knowledge and acceptance, we also analyze which contexts, methods, and theories are applied to track these characteristics or factors.

We created an Excel reading grid and separated all the factors into different columns based on the unique characteristics of each retrieval data. Then, we begin the analysis with characteristics or factors to determine how previous authors have addressed them.

3.1 The retrieved characteristics (factors) tracked in previous studies

We aim to discern the inherent factors directly impacting the successful completion of a Ph.D. Our dataset categorizes these factors into subgroups based on distinct, independent behaviors. Among the 38 studies analyzed, 27 studies, comprising 71.05% of the dataset, specifically address issues pertinent to Ph.D. success or timely completion. These characteristics are primarily governed by institutional, social, demographic, financial, and psychological factors. Institutional factors notably dominate discussions in previous literature, featuring in 65.79% of the studies (25 out of 38). Demographic factors follow closely, accounting for 34.29% (12 out of 38) of successful Ph.D. studies. Additionally, while other social factors exhibit a lower presence, they are not disregarded (3 out of 38, 7.89%). Moreover, an increased focus on financial factors has been observed (7 out of 38, 18.42%). Although less frequently discussed, psychological factors hold significance in 15.79% of the studies (6 out of 38). Importantly, these factors are interconnected, and their concerted alignment significantly drives successful Ph.D. completion.

3.1.1. Institutional factors

The success of Ph.D. candidates is intricately tied to various factors within the academic environment. Sinclair et al. (2014) emphasize the centrality of the process, asserting that well-structured and managed Ph.D. programs contribute significantly to the overall academic climate. Policies play a pivotal role in this, with student-friendly procedures and clear guidelines mitigating potential challenges, as suggested by Skopek et al. (2022) and Soin and Huber (2021). This is echoed by Bao et al. (2018), emphasizing the institutional commitment across European and Chinese universities to increase doctoral degree awards and reduce time-to-degree. Faculty support fosters creative writing abilities, ultimately enhancing publication outcomes (Kim & Karau, 2009; Sinclair et al., 2014). Conversely, issues such as misunderstandings with faculty and frustration with the university can contribute to attrition (Lovitts, 2002). Discipline-specific disparities impact thesis submissions, with academic discipline proving to be a reliable predictor of success (Humphrey et al., 2012). Here, cultural dimensions often align with hard (natural sciences) and soft (humanities or social sciences) categories (Haake, 2011), necessitating tailored training programs. Appointment status and cohort characteristics significantly influence success, with the nature of appointments affecting office benefits and student longevity (Neumann & Rodwell, 2009; Spronken-Smith et al., 2018; Vassil & Solvak, 2012). Institutions are crucial in providing socialization facilities to maintain student motivation (Castelló et al., 2017) and facilitating networking opportunities (Beasy et al., 2021). Research training aligned with the labor market is pivotal for career success, focusing on salary as a key measure (Canal-Domínguez & Wall, 2014). A proper supervisor-student duo and a supportive learning environment, characterized by the security of supervision and expectations of scientific participation, contribute to achieving the highest accreditation (Holzweiss, 2022; Jara, 2021; de Vogel, 2022). Increased student numbers and new practices, such as collaborative supervision, challenge universities to manage supervisory capacity (Jara, 2021; van Rooij et al., 2021). Research collaborations with industry have led to a rise in mid-career and late-career Ph.D. students who require a different support approach (Robertson, 2017). Publication pressure, deadlines, workload, communication with supervisors, and time constraints are significant stressors for Ph.D. candidates (Waaijer et al., 2016)—the emphasis on publication as a competition metric today. Jones (2013) poses challenges to cultivating a supportive institutional environment, particularly for early-stage Ph.D. students (Mertkan et al., 2022). Moreover, gender discrimination can adversely impact the Ph.D. experience, emphasizing the need for institutions to address such issues (Ann Danowitz, 2016).

Overall, 65% of the critical analyses of the collected studies underscore the multifaceted institutional responsibilities that significantly influence the success and experiences of Ph.D. candidates.

3.1.2. Social factors

Our prior discussions underscored the institutional role in fostering the socialization of Ph.D. students. Expanding on this discourse, 7.89% of the collection shares the influence of Ph.D. students’ familial, peer, and external networks, which merits attention. Kluever (1997) highlights the pivotal role of a student’s spouse, family, and friends as primary sources of emotional support, significantly impacting the dissertation process. While parental education might not correlate with attaining top grades in Ph.D. studies (de Vogel, 2022), they often serve as crucial financial supporters during the academic journey (Kluever, 1997). McCray and Joseph-Richard (2020) advocate diversifying social circles outside academia to foster a well-rounded network. The significance of social networking, including positive relationships with faculty and colleagues and a sense of belonging, emerges as pivotal for doctoral persistence (S. et al., 2012). Castelló et al. (2017) assert that balancing personal life, work, and social engagements during doctoral studies presents notable challenges, impacting doctoral progress. Emotional exhaustion, depression, and inadequate socialization with colleagues have been cited as reasons for incomplete Ph.D. pursuits, contributing to isolation and reduced intrinsic motivation (McCray & Joseph-Richard, 2020). The value of knowledge exchange through socialization among peers is emphasized by Liechty et al. (2009), while Burnett (1999) connects rapid student progress with peer communication, advocating for collaborative cohort models that mitigate isolation. These discussions underscore the pivotal role of socialization in the life of a Ph.D. student. Additionally, Spaulding and Rockinson-Szapkiw (2012) stress that socially engaged students exhibit reduced dropout tendencies, further emphasizing the importance of social connectivity in fostering doctoral success.

3.1.3. Demographic factors

Espenshade (1997) observes that international students in U.S.A. Ph.D. funding institutions tend to complete their doctoral programs earlier than local students, with a slightly higher success rate. Similarly, Groenvynck et al. (2013) found a higher success rate among non-EU researchers in European settings. Conversely, Wright and Cochrane (2000) presents a different perspective, suggesting that international students may face more challenges in achieving successful thesis submissions. Despite nationality, many Ph.D. students in Estonia need help with timely graduation or drop out, as Wright and Cochrane (2000) noted. Examining the correlation of gender and age with Ph.D. success reveals a nuanced landscape. There is an ongoing debate regarding male Ph.D. candidates expected higher earnings levels irrespective of their field (Canal-Domínguez & Wall, 2014). Females, however, exhibit a higher likelihood of dropout than males, with younger candidates more inclined to persist (Castelló et al., 2017). Additionally, Robertson (2017) suggests that early-career or younger Ph.D. students display more enthusiasm than those in later career stages. Vassil and Solvak (2012) further highlight age-related trends, indicating lower success rates for candidates above 40, with men showing a slightly higher completion rate. Different age brackets at the outset of research careers appear to affect Ph.D. success rates, with those under 26 being more successful than those over 40 (Groenvynck et al., 2013). Visser et al. (2007) corroborate these findings. However, contrasting results emerge in studies such as Wright and Cochrane (2000), suggesting that women might be slightly more successful in thesis submissions than men. Evidence indicates that women in humanities and social sciences place a more excellent value on career success (Canal-Domínguez & Wall, 2014). Fiset and Saffie‐Robertson (2020) highlight gender-based differences in negotiation and success in securing higher pay for male participants. 34.29%% of varying collections underscore the complex interplay of gender, age, and success in Ph.D. pursuits, reflecting diverse experiences across different cohorts of students.

3.1.4. Financial factors

Notably, in 18.42% of the collection, the high dropout rate is increasing due to limited funding. In this context, it has become essential for universities, government agencies, and funding bodies such as FRS-FNRS2 (‘Fund for Scientific Research’) to understand the doctoral process in depth and allocate resources accordingly (van der Haert et al., 2014). On the other hand, funding support for Ph.D. students is significant enough to attract suitable candidates to doctoral programs and prepare the workforce for the limited national and global postdoctoral labor market (Hnatkova et al., 2022; Marini, 2022).

Now, let us turn to the type of Ph.D. funding. Whether students focus entirely on the thesis, seek teaching responsibilities, or outside employment largely depends on the funding received, affecting the doctorate duration and the dropout rate (de Vogel, 2022; Skopek et al., 2022; Zhou, 2015). According to Visser et al., (2007), students with government funding achieve faster success. For example, in the Flemish government, the R&D investment happens by two funding agencies: FWO Vlaanderen and IWT-Vlaanderen, which produces more successful Ph.D. holders than other financial sources. On the other hand, those on temporary project-funded contracts, especially when these projects involve applied or policy-relevant research, often need more job security with less autonomy to focus on their doctoral research. As a result, their completion rates are lower, and time-to-degree is high (Groenvynck et al., 2013). In that case, employment contracts and scholarships should have a sufficient duration to provide adequate financial support to enable doctoral candidates to focus on their studies (de Vogel, 2022).

Surprisingly, junior researchers are more likely to drop out faster than others funded through applied research projects (Groenvynck et al., 2013). Wijnen et al. (2021) analyzed that males have 4% more chances to receive grants than women. The funding from the research council significantly affected the male completion rate (Wright & Cochrane, 2000). Unfunded Ph.D. students are more at risk of dropping out because they have to find alternative means of funding (van der Haert et al., 2014). Interestingly, (Castelló et al., 2017) claim that funding has no relationship to dropout decisions.

However, undermining all these discussions (Vassil & Solvak, 2012), the study shows that finance only sometimes ensures the success of Ph.D. students. As such, a Ph.D. student can drop out at any moment despite the total funding of about €50,000 in Estonian universities.

3.1.5. Psychological factors

Individual factors that always impact dissertation completion include psychological factors and skill preparation. These determine a learner’s autonomy, such as access to independent learning. Now, how does this autonomy affect the psychological factor? The tradition of intellectual independence has long been highly valued (Johnson et al., 2000). Developing and expressing critical thinking in students encourages autonomy (Jara, 2021). As discussed earlier, a Ph.D. student’s success highly depends on the relationship with the supervisor. Especially for International Ph.D. students, supervisors psychologically empower them to cope with and adapt to the Ph.D. process (Elliot & Kobayashi, 2019). Making this relationship successful (Janssen et al., 2021) mentioned the three needs: autonomy, competency, and relatedness. It challenges the smooth relationship between supervisor and student to balance freedom and competence (Ryan & Deci, 2017). Sometimes, it can cause tension (Janssen et al., 2021). Focusing more on independence, the Nordic and Central European countries offer informal and flexible doctoral programs where they plan with the freedom to work (Martinsuo & Turkulainen, 2011).

In addition, other psychological problems such as fear and anxiety (Strachan et al., 2004), impostorism (Tao & Gloria, 2019), and cognitions such as self-criticism and self-doubt (Gordon, 2003) hinder Ph.D. success. However, previous discussions have emphasized fewer aspects, such as difficulty managing stress and emotions or a perceived lack of research skills (Castelló et al., 2017). We track a few meaningful outcomes from the (Tao & Gloria, 2019) study about ‘impostorism.’ The phenomenon of imposter or ‘impostorism’ has been defined as the experience of high achievers (especially women) who, despite being successful, attribute their achievements to luck and fear of being exposed as frauds. Of their sample, 82% described experiencing at least a low level of impostor incidence with low self-efficacy at any point in their Ph.D. program. Jöstl et al., (2012) also agrees, if this phenomenon continues, the high number of imposter students will lead to a high chance of lower self-efficacy in the institute.

Furthermore, organizations’ ‘Publish or no degree’ policy may create unethical debates with low self-efficacy (Mertkan et al., 2022). Additionally, the authors added that students’ continued rejection from assigned journals could lead to a loss of self-confidence, promoting an invalid degree.

The above discussion of characteristics/factors leads us to explore the following three TCCM components. They are method (M), context (C), and finally, theory (T). Nevertheless, first, we will discuss previous authors’ techniques and procedures for factor retrieval.

3.2.1. Techniques followed for the establishment of properties (methods)

We meticulously replicated the methodologies employed by previous researchers to identify these characteristics, aiming to comprehend their approach to uncovering these findings. Notably, prior studies exhibited various methods used for robust data collection. Data was classified into primary and secondary sources, with primary sources predominantly comprising interviews, surveys, questionnaires, and reflective diaries. The prevalent utilization of case study methods was observed in data collection processes, with influential authors, such as Humphrey et al. (2012) and Skopek et al. (2022), aligning themselves with the longitudinal case study approach. Interestingly, these authors diverged from conventional methodologies, opting for narrative diaries to extract empirical insights into the doctoral journey, contrasting with the strategies of McAlpine et al. (2020) and Smith McGloin (2021).

Turning to secondary data sources, studies drew from diverse archives, exemplified using the German Ph.D. Panel Study (de Vogel, 2022) conducted by the German Centre for Higher Education Research and Science Studies, the Human Resources in Science and Technology survey for case study development (Canal-Domínguez & Wall, 2014), and direct data retrieval from former Syracuse University Ph.D. students (Grove et al., 2007). Gruzdev et al. (2020) adopted a hybrid approach, amalgamating primary data from interviews with international Ph.D. students and supervisors, followed by quantitative survey data from the Russian Academic Excellence Initiative-Project 5–100 and federal universities.

Our study resulted in a dataset comprising a mix of methodologies: 36.84% qualitative, 28.94% quantitative, and 34.21% employing a mixed-method approach. Seven distinct statistical methods were applied to analyze this data, detailed in Table 1. This critical overview showcases the diverse methodological landscape utilized in prior studies, highlighting innovative and traditional approaches to unravel the intricacies of Ph.D. success factors.

Table 1. Methodologies and number of studies.

Focused area	Types	Methods	Number of studies
Ph.D. success factor or in-time completion	Data types	Primary data
		Interview Survey The questionnaire studies Reflective diaries Secondary data Archived Document	12
			9
			1
			2
			15
	Types of approaches	Qualitative studies	14
		Quantitative studies	11
		Mixed studies	13
	Types of statistics	Regression analysis	14
		Descriptive analysis	9
		Correlation analysis	3
		T-Test	1
		Chi-Square	7
		Factor analysis	4
		MANOVA	1

3.2.2. The geographical area of study (context)

From our retrieved data, 94.74% is a place-based study. Therefore, we want to know which context or country prior authors use to determine the factors. This process also helps us understand the occurring variables in the factors. The growing number of studies and their patterns have improved our knowledge by identifying different contexts related to Ph.D. success. This allows us to carry out research with an overview of countries worldwide. The frequency of countries used as context is evidence of the author’s interest in specific countries or geographic areas about the causes of Ph.D. success. From the extracted data list, 34 studies selected a single country as context, two chose multiple countries, and the remaining two conducted a general study. Interestingly, all countries’ geographic areas are detected in developed zones. The following Graph shows the list of contexts in different studies.

Graph. Geographical distribution of studies in Ph.D.

3.2.3. The logical association with factors (theories)

Now, let us discuss the theory prior authors applied to dig out the factors. Previous researchers use different theories to explain PhD-related issues; however, these issues directly or indirectly influence Ph.D. success. Smith McGloin (2021) applied new mobility paradigms to explore the experiences of Ph.D. students during their journey linked to progress at the institutional level. Also, their research highlighted the process of knowledge creation of Ph.D. students satisfying deadlines. McCray and Joseph-Richard (2020) elaborate research with Resilience Theory, describing Ph.D. students’ responses, social connections, environment, and institutional support as interdependent in the Ph.D. success process. Robertson (2017) theorizes social cognitive theory to determine ‘the self-efficacy of mid-career candidates whose ages within 35/44 reinforce their performance. Tao and Gloria (2019) also apply social cognitive theory to assess Ph.D. students’ psychological state as self-efficacy driving timely completion. In-time Ph.D. completion is also described with the concept of Credentials theory by Horta et al. (2019), as Ph.D. funds are allocated for a specific time, so publishing and time strategy are needed for successful completion. Ward and Brennan (2020) use the Theory of fit to signify the surrounding fit associated with Ph.D. students’ performance. Zhou’s (2015) motivation theory unfolded. Ph.D. students’ intrinsic motivation gradually changes. Gruzdev et al. (2020) Self-determination theory supervisor’s role in-time completion. Elliot & Kobayashi (2019) also prioritizes the supervisor’s role in the successful experience, but the authors bridge Urie Bronfenbrenner’s bioecological theory with Hofstede’s theory, explaining the supervisory process in the Ph.D. experience. Kiley (2017), following the prior research on a supervisory role, the author wants to explore the case through a dual lens. Interestingly, the Threshold concept of theory conveys the supervisor and Ph.D. student’s experience at the same time. Authors such as, (Ann Danowitz, 2016; Fiset & Saffie‐Robertson, 2020; Haake, 2011) focus more on gender as they think; this is a crucial factor in Ph.D. success, determining their notion, applied congruence theory, Cognitive psychology theory, and Bourdieu’s theory, respectively. Furthermore, Castelló et al., (2017) dispense Theory’s Notion of Motive to learn about the motive to be a dropout, while Mertkan et al., (2022) argue that pressure to publish puts a negative experience that hinders Ph.D. success, justifying the use of two theory Figured worlds theory and agency theory.

4. Discussions

This study’s primary aim is to clarify to stakeholders the intricate dynamics influencing Ph.D. success, intending to shed light on factors pivotal to achieving a Ph.D. This investigation delves into the experiences of Ph.D. students, scrutinizing the multifaceted roles these factors play in shaping Ph.D. acceptance, whether as singular influencers, combined forces, or non-contributors. Despite the sustained attention Ph.D.-related matters have garnered due to high dropout rates, the need remained pressing for a comprehensive synthesis of prevailing issues, prompting this study as one of the inaugural systematic literature reviews employing a combined approach—utilizing the 8-step process, PRISMA, and TCCM—aimed at unraveling the driving forces behind Ph.D. success.

The findings from many studies comprising 38 meticulously curated pieces illuminate the challenges and dimensions integral to a successful Ph.D. Journeying through these studies, it becomes evident that while prior authors frequently discuss similar factors, the outcomes presented diverge or echo each other, often influenced by contextual variations and the diverse nature of data. For instance, the psychological factor of ‘Imposterism,’ explored by Tao and Gloria (2019) and Jöstl et al. (2012), concurs with its substantial impact, notably reducing self-efficacy and fostering a fear of failure among Ph.D. students. Similarly, while Van der Haert et al. (2014) argue that insufficient funding amplifies the likelihood of Ph.D. dropout, Castelló et al. (2017) counter this notion, asserting no correlation between funding availability and dropout decisions. On the other hand, Vassil and Solvak (2012) propose that despite adequate funding, Ph.D. students retain the autonomy to discontinue their studies. Institutional factors emerge as a dominant theme across the spectrum of studies, with scholars such as Skopek et al. (2022), Soin and Huber (2021), and Sinclair et al. (2014) converging on the substantial influence institutions wield in determining Ph.D. student success. This factor analysis predominantly aligns with the ‘Characteristics (C)’ category within the ‘TCCM’ framework, augmented by explorations into Theory ‘T,’ Method ‘M,’ and Context ‘C’ for deeper insights.

Implications of this study extend beyond mere elucidation of these factors; it aims to provide actionable guidance to stakeholders—government bodies, institutions, funders, and students—urging a strategic recalibration to bridge knowledge gaps and refine strategies. By identifying five independent factors—Institutional, social, demographic, financial, and psychological—this study partially responds to the overarching query on factors driving Ph.D. success. Drawing from diverse authors’ explanations, this study offers justifications on ‘How and Why’ these factors influence success, amalgamating insights from qualitative, quantitative, and mixed methodologies across 17 theories.

Contributing substantively to the educational domain and researchers’ growth, this study elucidates answers within scientific frameworks, justifies research conclusions, and constructs a comprehensive figure—Figure 4—laying a foundation for future empirical analyses. Notably, it contributes to scientific discourse by unpacking factors’ positive and negative implications on future researchers’ development while illuminating divergent perspectives held by prior authors.

Figure 4. The factors and their association with Ph.D. success.

Despite striving for scholarly discourse, limitations persisted. The need for more studies in reputable journals posed challenges in synthesis, with field research often needing more quality assurance. This lacuna prompts a call for further research, urging exploration in uncharted territories within the Ph.D. domain to deepen our understanding. Thus, while this study endeavors to mitigate knowledge gaps, it underscores the need for rigorous research methodologies and invites future investigations to delve deeper into unexplored facets of Ph.D. trajectories.

5. Conclusion

The study was conducted to systematically elucidate the existing discourse on the determinants of a successful Ph.D. Our examination of 38 meticulously chosen studies unearthed various challenges intrinsic to the Ph.D. journey, providing insights into the fundamental elements driving Ph.D. success. Notably, the influential role of institutions offering Ph.D. programs is emphasized, signifying their critical impact on student achievement. However, persistent challenges persist in accommodating the expanding Ph.D. community across diverse research domains, thereby influencing candidate qualification, supervision, and the creation of supportive environments. External factors, including social networks and demographic variables such as age, nationality, and gender, significantly mold Ph.D. trajectories, albeit with some studies, such as Groenvynck et al. (2013) and Wright and Cochrane (2000), presenting differing perspectives. Psychological well-being emerges as a pivotal factor, with confidence, fear, and self-doubt strongly influencing success rates. Additionally, financial considerations, especially funding sources, wield a significant influence in ensuring successful Ph.D. completion.

The study represents a pioneering use of qualitative content analysis within a methodological framework that integrates PRISMA, the TCCM framework, and an 8-step process, marking a substantial advancement in this field. Employing PRISMA for data retrieval, our application of the TCCM framework allowed us to identify five influential characteristics (factors) across 17 theories from nine countries, utilizing diverse methodological approaches. The study encompassed 36.84% qualitative, 28.94% quantitative, and 34.21% mixed methods, employing seven distinct statistical techniques to glean multifaceted insights. Highlighting a prevailing focus on developed countries, the findings underscore the imperative to explore international Ph.D. student experiences. A significant contribution to the literature is Figure 4, which illustrates the evolution of prior literature and delineates how various characteristics exert positive, negative, or zero influence on Ph.D. success. Furthermore, we comprehensively examined divergent perspectives by critically analyzing and comparing previously discussed factors, such as the discussions by de Vogel (2022) and Vassil and Solvak (2012) on Ph.D. students’ financial positions. Integrating these arguments within the TCCM framework, the study addresses the research question by elucidating the factors influencing a Ph.D. journey, as depicted in Figure 4.

This study’s significance extends to its comprehensive analysis of pivotal factors, offering practical implications for institutions, stakeholders, funders, and policymakers to foster an environment conducive to Ph.D. success. Identifying five core characteristics and their subfactors contributes substantially to understanding institutions and policymakers’ role in structuring Ph.D. programs. Policymakers and funders gain insights into Ph.D. student enrollment and the flow of qualified researchers in markets. Institutions can strategize to leverage the positive influences of these factors and establish effective communication channels to mitigate adverse outcomes, safeguarding against monetary and temporal losses while nurturing future researchers. This study serves as a preparatory guidebook for prospective Ph.D. students, helping them comprehend the implications of various factors and mentally prepare for the challenges and rewards of Ph.D. life. It aims to foster trust among Ph.D. students, enabling them to navigate diverse situations while maintaining a focus on the quality of their research endeavors.

Limitations and future research directions

One might raise a critique concerning the adequacy of concluding the entire Ph.D. journey based on the analysis of 38 studies. Evaluating the study’s quality and publication years may influence its reliability and acceptance. Our review of these studies has enabled the identification of gaps within theories, characteristics, context, and methodologies. Within the framework utilized, several potential areas for future exploration emerge. Firstly, Table 2 showcases frequently employed theories in analyzing Ph.D.-related concepts, emphasizing factors contributing to success or failure. Future research might consider employing the behavioral reasoning theory (Westaby, 2005) to understand why certain factors positively or negatively impact human behavior, thereby clarifying the entirety of the concept. Secondly, Smith McGloin (2021) introduces a thought-provoking approach that encourages critical examination of doctoral spaces, focusing on how supervisors and administrative staff shape environments, considering students’ personal and professional aspirations through networking and exploring students’ networking as a potential characteristic warrant further investigation. Thirdly, our observation of a Western-centric research context across the 38 studies highlights a potential bias. Future research could diversify by exploring Asian contexts like India and China. Lastly, a proposed publishing matrix tool for future research could facilitate tracking the dissemination of Ph.D. success-related information. This would aid stakeholders in understanding which messages or factors merit attention. Such an approach would also equip authors with explicit insights into audience preferences and content value, optimizing communication effectiveness for each factor addressed.

Table 2. Theories and their frequency of application.

Name of theory	Frequency of application
Social cognitive theory	2
Bourdieu’s theory (1988)	1
Theory’s Notion of Motive	1
The concept of Credentials	1
Congruence theory	1
Urie Bronfenbrenner’s bio-ecological theory	1
Figured worlds	1
Individual agency	1
Cognitive psychology theory and Politics of Imagery	1
Self-determination theory (indirect discussion)	1
Mobilities Paradigm	1
The Theory of fit	1
Motivation Theory	1
Threshold concept of theory and grounded theory	1
Resilience Theory	1
Self-determination theory	1
Relational Schema theory	1
Grand Total	18

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Farhana Yeasmin

I am Farhana Yeasmin, and I start my Ph.D. at the University of Agder (UIA) in the strategies and management department. The literature I'm currently engaging with is intricately linked to the collective journey of all students traversing the path of higher education. I aspire that this literature, enriched by shared experiences and scholarly insights, will serve as a compass, smoothing the intricate and challenging trajectory that lies ahead for future scholars.