PhD Degrees: Definition, Application Requirements, and Key Considerations

PhD Degrees: Definition, Application Requirements, and Key Considerations
Imed Bouchrika, Phd by Imed Bouchrika, Phd
Chief Data Scientist & Head of Content

Students who embark on a journey for their Doctor of Philosophy are reaching the peak of educational achievement. After all, a PhD degree signifies one’s expertise in his or her chosen field. Moreover, a PhD degree indicates knowledge that’s sufficient to unlock more advanced career opportunities. In many cases, for instance, PhD degree holders can join the academe to teach at universities. Many also go on to pursue advanced research and further established knowledge in their specific fields.

However, embarking on this journey can be overwhelming. As such, among the steps that anyone considering to get a PhD degree should take is to learn more about it. This article aims to discuss in detail all the basic information relating to PhD, from its definition to the key factors at play when pursuing a PhD degree. It will also discuss what students can expect upon being accepted into a PhD program and provide some tips for success as well.

In all, this article will serve as a good resource for graduate students aspiring to earn a PhD by providing them with information and recommendations that can help them gear up for the journey.

PhD Degrees Table of Contents

  1. What is a PhD?
  2. Motivations to Pursue a PhD Degree
  3. PhD Requirements
  4. Key Factors & Considerations to Enroll for a PhD
  5. Tips for Graduate Students Who Want to Earn a PhD

What is a PhD?

The number of graduate students pursuing a PhD has been rising over the past few years. The number of American adults with an advanced degree has increased from 8.6% in 2000 to 13.1% in 2018. Of this, 4.5 million are doctoral degree holders (U.S. Census Bureau, 2019). That said, one might ask, “what is a PhD?”

A PhD is a postgraduate academic degree recognized all over the world. Doctoral degrees, including PhDs, have been part of higher education ever since the first was conferred in the 12th century by the University of Paris (Noble, 1994). Before the existence of PhDs, the highest level of academic ranking was a master’s degree. PhDs were developed to recognize those who go beyond their master’s degree in terms of contributing new knowledge to the field (FindAPhD, 2018). 

A PhD is the highest level of education that a student can obtain after submitting a qualified thesis or dissertation based on original research and data analysis. In general, PhDs are designed for graduate students who wish to conduct original and applied research meant to test a theory, with the ultimate goal of contributing to the existing knowledge in their field (Walden University, n.d.). 

A PhD program allows students to perform and achieve the following:

  • Analyze existing theories and concepts in their areas of discipline further
  • Evaluate and verify the relevance of emerging trends and theories in their fields
  • Identify gaps in the existing research literature
  • Contribute new knowledge through original research
  • Reach out and communicate to academic stakeholders and audience more effectively

Traditionally, PhD programs involve three to four years of full-time studying. Students typically spend a significant portion of these years working on their original research. However, the specificities of PhD programs vary depending on the institution and area of discipline. 

Some institutions accept portfolios of students’ published and verifiable research papers, while some may require additional coursework. There are institutions that also give students an opportunity to fast-track or upgrade their master’s degree to a PhD as long as they meet the grade, skills, and research qualifications (QS Top Universities, n.d.).

Source: U.S. Census Bureau

Types of PhD

When people talk about types of PhD, they often refer to the types of doctoral/doctorate degrees. PhDs are the most common type of doctorates, which is why many people tend to interchange the two terms.

PhDs are awarded in most academic fields, making them an academic doctoral degree. Other doctorates, which are called different titles, are awarded for specific subject areas that are often professional in nature. These are classified as professional doctorates. Below are some examples:

  • Doctor of Business Administration (DBA)
  • Doctor of Engineering (EngD/PhD Eng)
  • Doctor of Education (EdD/DEd)
  • Doctor of Social Science (DSocSci)
  • Doctor of Professional Studies (DProf)
  • Doctor of Architecture (DArch)
  • Doctor of Science (Dsc/ScD)
  • Doctor of Theology (ThD)
  • Doctor of Literature (LittD/DLitt)

To elaborate, these are the four main types of doctorate degrees:

  • Academic doctorates – This is where PhD and ThD are classified under. Academic doctorates are awarded after the student completes original research in a traditional academic subject. The primary purpose of academic doctorates is to broaden the theoretical understanding of a particular subject.
  • Professional doctorates – This type of doctorate degrees are awarded to professionals whose work directly contributes new knowledge and improvements to their specific professional field. Professional doctorate programs also require original research and analysis, but with the addition of practical application, training, and instruction. Examples of this type of doctorate are DBA, EngD, and EdD.
  • Higher doctorates – These are normally awarded later in a graduate or professional’s career to recognize their contribution to their area of discipline. These are not completed by enrolling in a university.
  • Honorary doctorates – As with higher doctorates, this type of doctorate does not require enrollment to a program as well. Honorary doctorates are awarded to celebrate an individual’s achievements. Unlike higher doctorates, however, this type of distinction does not require professional or academic work. The awarding institution can grant this to anyone they deem fit and deserving.

A good example to illustrate these differences is the case between two popular types of doctorate degrees. According to Sherman et al. (2017), the doctor of public health (DrPH) degree—a post-graduate training program that physicians undergo—is commonly considered as a professional degree, whereas a doctor of philosophy (PhD) degree is considered as an academic degree.

Motivations to Pursue a PhD Degree

As glorious as it may sound, getting a PhD is no small feat. For one, as it would mean spending years completing original research, a student may need to pass on the chance to earn real money as a working academician. Before one decides to enroll in a PhD program, he/she needs to have their motivations and reasons in the right place.

Taking the PhD path can be daunting, but if an aspiring student focuses on any or all of these motivations, they may feel better inspired to pursue and finish a program.

It provides the opportunity to make a difference.

Anyone who takes even the slightest interest in getting a PhD is likely committed to the improvement of their field. A PhD provides an avenue for graduate students to contribute to their field even further after completing a master’s degree. A PhD gives students the opportunity to make an impact from their research contributions, which are published with the purpose of assisting the advancement of knowledge.

It makes one a certified expert in a field.

Earning a PhD means that a graduate has acquired a profound amount of knowledge and level of expertise in a particular field. This makes them authority figures that can offer their opinion and expertise on matters related to their area of discipline.

It opens doors to more career options.

In the U.S., about 989,000 students graduated with an associate degree and 1.9 million students graduated with a bachelor’s degree in 2019. Meanwhile, 820,000 students acquired master’s degrees and 184,000 were awarded doctorate degrees (Bustamante, 2019).

Most of these graduates join the workforce as soon as they finish studying, making the job market as competitive as ever. In fact, National Science Foundation data indicates that PhD degree holders, within three years after graduation, tend to have overall high employment rates, although there are some disparities among different fields (Rahm et al., 2015). Indeed, PhD degree holders tend to have an academic advantage over college and master’s degree graduates. Moreover, there are job opportunities specifically targeted at PhD holders.

It is also worth noting that just recently, it was found that the U.S. private sector now employs nearly as many PhD holders as academic institutions do (Langin, 2019). This goes to show that PhD degree holders are not limited to opportunities related to the academe.

It helps increase salary potential.

For PhD holders ready to join the workforce once again, the distinction may entitle them to higher salary offers. This makes a PhD not only a viable academic investment but a financial one as well.

As the world continues to be engulfed by technological innovations, doctorate holders are creating new career opportunities. For instance, PhD economists have begun to assume an increasingly vital function in technology firms, handling issues like policy, pricing, and platform design (Athey & Luca, 2019).


PhD Requirements

Admission requirements

In general, one of the primary PhD requirements is the applicant’s grades from their bachelor’s and master’s degrees. Globally, it is typical for some institutions to only accept applicants with an honors degree. Some universities accept candidates who have completed their bachelor’s degree with upper second-class honors or higher and their master’s degree with high academic standing. 

Furthermore, a candidate’s bachelor’s and master’s degree grades also matter when applying for PhD funding. Typically, higher grades grant a candidate better funding options. Those who will fund their PhD on their own may be allowed to apply even with lower grades.

On average, most graduate institutions expect doctorate degree applicants to have GPAs between 3.3 to 3.5. However, other factors such as courses taken during the bachelor’s or master’s degree program will also be evaluated to weigh the gravity of a GPA.

It is also worth noting that in the U.S., a master’s degree is not a strict requirement for PhD admission. A bachelor’s degree holder with an outstanding GPA can try directly applying for a PhD program (Academic Positions, 2018). However, PhD admission with only a bachelor’s degree may prove extra challenging and competitive as the student might not have taken advanced classes or completed a significant thesis during their undergraduate course.

Aside from meeting degree and grade-based qualifications, candidates are also commonly required to find a tenured professor to serve as their formal advisor or supervisor throughout the course of their program. In some cases, candidates are matched with a supervisor once they are accepted to the PhD program. 

Either way, candidates are better off approaching a professor who they believe can help them in their research before applying for a PhD. Doing so also helps the candidate assess whether the institution and the respective department are both aligned with their research interests. Consulting a professor beforehand may also open the opportunity for brainstorming viable research focus and options.

Application requirement

Aspiring students who meet the basic admission requirements can proceed to apply for a PhD program. Below are the general PhD application requirements:

1. Language proficiency

Some institutions and programs require proof of English language proficiency such as Test of English as a Foreign Language (TOEFL) or International English Language Testing System (IELTS). This is particularly important to foreign students hoping to earn a PhD degrees in the U.S. Applicants may need to provide the results of their standardized language exam. In some cases, providing proof that they finished their undergraduate or postgraduate study in the language they want to study the PhD in.

2. Academic and employment references

Typically, universities require PhD candidates to submit their academic transcripts. Records of previous research work and publications can also help one’s application. Aspiring PhD students may also be asked to present employment records, including their résumé and certificates of employment, if applicable. 

Furthermore, students may also seek reference letters from professors and employers that can be used to validate their purpose and qualification for a PhD.

3. Personal statements or essays

It is common for universities to ask for a personal statement or essay that will demonstrate the candidate’s passion for their chosen subject and in a way, their language proficiency and eloquence. The essay may outline the candidate’s reasons and motivations for wanting to enter a PhD program. The personal statement can be used to highlight the student’s education and work background as well.

4. PhD research proposals

As a PhD degree is largely about academic research, candidates need to prepare a research proposal. The proposal ideally showcases the following:

  • The outline of the proposed research topic
  • The candidate’s awareness of current trends and debates in their field
  • The research and knowledge gaps that the candidate’s research hopes to fill
  • The suggested hypotheses relevant to the research scope
  • The research methodology that will be used
  • The implications and outcomes that may result from the research

The research proposal will help the institution’s admission authorities to assess the candidate’s aptitude for a PhD program and whether the direction of his/her planned research aligns with the university’s own research focus and facilities. The admission tutors will also consider if their institution has sufficient means and suitable staff to provide the candidate with the assistance and supervision they would need.

5. Special requirements

PhD candidates should also prepare to meet other special requirements specific to the institution or field of study they choose aside from the application requirements listed above. The process by which candidates apply and get admitted to a program may also vary from one institution to another.

Key Factors & Considerations to Enroll for a PhD

A PhD can serve as one’s peak of formal academic study and training. As to be expected, completing a PhD can bring forth several positive outcomes. However, the journey to PhD success begins by knowing and considering as much of these factors and information as possible.

The need, desire, and motivation to get a PhD

Before anything else, a student must look deep within to determine whether he/she truly desires and need to go through this journey. As mentioned above, taking up a PhD can be quite overwhelming and daunting. Focusing on the desire to earn a PhD and ultimately contribute to the field and society can help a student make more rational decisions. 

The student’s area of interest

Aspiring PhD students should first read up and dig as much as they can about their areas of interest. Some of the things to find out are previously published studies relevant to the chosen topic. The student may also research faculty profiles to find out if any of them can provide sufficient guidance and supervision. 

Ultimately, the student needs to determine whether the research angle and research question he/she has in mind is relevant and interesting enough to invite curiosity and audience. They should also evaluate if the results of their research have the potential to contribute to the field significantly.

The supervising professor

The student’s choice of supervisor is crucial to their success. The supervisor’s role is to guide the students in the right direction to ensure that they do not stray from their research focus. The professor is supposed to give the students advice and recommendations, especially when they encounter issues along the way. 

Because of the supervising professor’s role, it is necessary that the students find one that they can trust and feel comfortable working with. More importantly, they should also look at the professor’s expertise and overall reputation in the academe.

The reputation of the university

Students should also consider the overall reputation of the university before they send their PhD applications. It would be wise to look at the university’s research background and teaching performance. It is also worth checking the availability of international education opportunities. Doing this will help students gauge whether a university’s academic reputation meets their expectations and matches their goals.

The source of funding

Students planning to get a PhD also need to prepare financially. On average, PhDs in the U.S. can cost around $28,000 to $40,000 annually. Students should keep in mind that a doctorate could take most of their time and attention, so much so that they might not be able to work and study at the same time. This may eventually affect their finances.

When it comes to funding their PhD, students generally have two options: fund their education with their personal money or seek financial assistance. In 2018, the highest source of doctorate funding (33%)  was research assistantship or traineeship. Meanwhile, 25.3% came from fellowships and grants. Students who are contemplating about getting a PhD but worried about the costs can check out funding options available to them.

Source: Statista

Tips for Graduate Students Who Want to Earn a PhD

Earning a PhD can change one’s life for the better. To help ensure that the journey is more enjoyable and fruitful, here are some tips from Bavel et al. (2018) for graduate students who want to earn a PhD.

Stay true to one’s interests.

First and foremost, aspiring PhD students need to consider their goals. Then, they should define if their research interests match those goals. The rest of the decisions they make will definitely have to revolve around their goals and interests, as those will help them stay in focus.

Research from start to end.

PhD programs are all about research and students need to be prepared to do a lot of it. They should not get tired of researching information and opportunities alike. For instance, it will be wise for students to begin by researching institutions with programs and inclinations relevant to the research topic or angle they want to focus on. 

Broaden the search and application.

Aspiring PhD students have the freedom to apply to more than one program or institution in the U.S. as there is no central organization that controls PhDs here, unlike in the U.K. and Europe (, n.d.). If a student was able to obtain sufficient information about the institutions they are considering to attend, such as admission qualifications, it will be easier for them to send applications to those institutions. Generally, it could be better to have more than one option when the time to choose an institution comes.

Make the application statement and research proposal shine.

Acceptance of students’ application to a PhD program largely depends on their qualifications and submissions, particularly their personal statement and research proposal. Thus, it is a given that these two must stand out. To do that, the students need to take their motivations and initial research seriously. It may also help to look at a research proposal example or two just to make sure the proper format is followed.

Seek references early.

Students need to secure referral letters at least a month before application deadlines. They must keep in mind that their employers and professors are busy individuals who may need ample time to prepare their referrals.

Is Applying for a PhD the Right Choice for You?

By undertaking a PhD, graduate students can become an expert in their fields. Their distinction will not only be recognized in the U.S. but globally as well. However, there is no one correct answer to the question of whether a PhD is the right choice for individuals looking to advance their academic and career standing. 

The information and tips laid out in this article seek to help students considering taking a PhD make informed decisions. Aside from these, however, it will also help students to seek advice from their professors and colleagues. Speaking to current PhD students may also give a clear idea of what they can expect once they get admitted to a program. 

Ultimately, a PhD is bound to prove as a worthy investment for academic or career advancement. But whatever decision one makes, it should be based on his/her own goals and level of commitment.

Useful Links:

Below are links that can help students get started on their search for a PhD program:



  1. Academic Positions (2018). Master’s first or straight to PhD? AcademicPositions.
  2. Athey, S., & Luca, M. (2019). Economists (and economics) in tech companies. Journal of Economic Perspectives, 33 (1), 209-230.
  3. Bavel, J., Gruber, J., & Lewis, N. (2018, September 26). Applying for a Ph.D.? These 10 tips can help you succeed. Science Mag.
  4. Bennett, M. (2019). Do university rankings matter for PhD study? Tips and tricks. The FindAPhD Blog.
  5. Bustamante, J. (2019). College graduation statistics.
  6. Duffin, E. (2020, January 8). Doctorate recipients’ primary sources of financial support in the United States in 2018. Statista.
  7. FindAPhD. (2018). PhD Study – What is a PhD? The FindAPhD Blog.
  8. FindAPhD. (n.d.). Types of PhD. The FindAPhD Blog.
  9. FindAPhD. (n.d.). Why do a PhD? The FindAPhD Blog.
  10. Langin, K. (2019, March 12). In a first, U.S. private sector employs nearly as many Ph.D.s as schools do. Science Mag.
  11. Noble, K. (1994). Changing Doctoral Degrees: An International Perspective. Buckingham, England & Bristol, PA: Society for Research into Higher Education and Open University Press. WorldCat
  12. PhDStudent (n.d.). Role of GPA: Before, during, and after grad school.
  13. PostGrad (n.d.). PhD in USA.
  14. QS Top Universities (n.d.) What is a PhD? QS Top Universities.
  15. Rahm, D., Brittain, V., Brown, C., Garofalo, C., Rangarajan, N., Shields, P., & Yun, H.J. (2015). Exploring the demand for PhDs in public affairs and administration. Journal of Public Affairs Education, 21 (1), 115-128.
  16. Sherman, B.R., Hoen, R., Lee, J.M., & Declercq, E.R. (2017). Doctor of public health education and training. Public Health Reports, 132 (1), 115-120.
  17. UL Lafayette Graduate School (2017). 5 reasons to get a PhD. UL Grad School’s Blog.
  18. U.S. Census Bureau (2019). Educational attainment in the United States: 2018.
  19. U.S. Census Bureau (2019). Number of people with master’s and doctoral degrees doubles since 2000.
  20. Walden University (n.d.) What’s the Difference Between a PhD and a Professional Doctoral Degree? Minneapolis, MN: WaldenUniversity.

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