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Nigeria vs Sierra Leone

On research quality in 2022-now, Nigeria ranks #101 in the world and Sierra Leone #112, of 189 countries. Nigeria stands higher in 25 of the 26 fields both publish in, Sierra Leone in 1.

Research profiles alike: 0.85very similar shapes of research, whatever their size. How it is measured

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Nigeria

World rank, 2022-now
#101
#104 all time
Works, 2022-now
134k
fractional
Top-10% rate
4.9%
share of its work among the world's most cited
Open access
70%
of its works free to read

Strongest relative focus: Library and Information Sciences, Drug Discovery, Chemical Health and Safety.

Sierra Leone

World rank, 2022-now
#112
#98 all time
Works, 2022-now
1.1k
fractional
Top-10% rate
6.6%
share of its work among the world's most cited
Open access
68%
of its works free to read

Strongest relative focus: Horticulture, Applied Microbiology and Biotechnology, Development.

Who leads, measure by measure?

Sierra Leone leads on 5 of 9 measures: citation excellence for its fields, top-10% rate, citations per work, international co-authorship and growth. Nigeria leads on 3 of 9 measures: research quality, output and open access. The two are level on institutions in the world top 100.

Nigeria 31 level5 Sierra Leone
  1. #101Research qualityworld rank of 189 countries, 2022-now#112
  2. 0.52×Citation excellence for its fieldsits top-10% rate against what its topics predict; 1.00× is as expected0.93×
  3. 134kOutputfractional works, 2022-now1.1k
  4. 4.9%Top-10% rateshare of its works among the world's most cited6.6%
  5. 7.4Citations per workall time, per fractional work8.9
  6. 0World top 100institutions it holds among the world's best 1000
  7. 70%Open accessof its works free to read, all time68%
  8. 16%Internationalof its works written with co-authors abroad, all time39%
  9. +22%Growthworks in 2022-25 against 2018-21; half a bar is no change+104%

A rank is drawn as its standing: the longer the bar, the nearer the top. Anything else is drawn against the larger of the two, and two values a hair apart are called level. Quality, citation excellence and the top-10% rate are explained in the methodology.

Who leads in each field?

Nigeria stands higher in 25 of 26 fields, Sierra Leone in 1. Nigeria leads most in Medicine (#84 against #99); Sierra Leone leads most in Social Sciences (#107 against #113). Each bar is that side's standing among all countries ranked in the field: the full bar is first place.

Nigeria 251 Sierra Leone
  1. #103Agricultural and Biological Sciences-
  2. #80Arts and Humanities-
  3. #93Biochemistry, Genetics and Molecular Biology-
  4. #92Business, Management and Accounting-
  5. #42Chemical Engineering-
  6. #63Chemistry-
  7. #112Computer Science-
  8. #70Decision Sciences-
  9. #60Dentistry-
  10. #66Earth and Planetary Sciences-
  11. #79Economics, Econometrics and Finance-
  12. #71Energy-
  13. #96Engineering-
  14. #105Environmental Science-
  15. #85Health Professions-
  16. #59Immunology and Microbiology-
  17. #74Materials Science-
  18. #75Mathematics-
  19. #84Medicine#99
  20. #65Neuroscience-
  21. #59Nursing-
  22. #43Pharmacology, Toxicology and Pharmaceutics-
  23. #74Physics and Astronomy-
  24. #95Psychology-
  25. #113Social Sciences#107
  26. #29Veterinary-

Standing is the percentile of world rank within each field, 2022-now; the printed number is the rank itself. A dash means the field is too small there to rank. How sides are compared.

The numbers behind each field

Click a heading to sort. The side that does better in a pair of columns is shaded: a lower rank, a higher rate, more works.

Field Nigeria rankSierra Leone rank Nigeria top 10%Sierra Leone top 10% Nigeria worksSierra Leone works
Agricultural and Biological Sciences #103 - 4.0% - 14k -
Arts and Humanities #80 - 8.7% - 2.8k -
Biochemistry, Genetics and Molecular Biology #93 - 4.5% - 4.6k -
Business, Management and Accounting #92 - 4.9% - 7.7k -
Chemical Engineering #42 - 6.5% - 200 -
Chemistry #63 - 6.0% - 1.6k -
Computer Science #112 - 5.7% - 8k -
Decision Sciences #70 - 4.8% - 2k -
Dentistry #60 - 3.5% - 409 -
Earth and Planetary Sciences #66 - 5.8% - 1.5k -
Economics, Econometrics and Finance #79 - 5.0% - 6.5k -
Energy #71 - 4.2% - 1.7k -
Engineering #96 - 4.9% - 14k -
Environmental Science #105 - 4.4% - 10k -
Health Professions #85 - 6.1% - 4.3k -
Immunology and Microbiology #59 - 5.0% - 1.3k -
Materials Science #74 - 6.6% - 2.8k -
Mathematics #75 - 6.3% - 1.9k -
Medicine #84 #99 4.1% 8.7% 21k 209
Neuroscience #65 - 5.2% - 739 -
Nursing #59 - 3.3% - 1.9k -
Pharmacology, Toxicology and Pharmaceutics #43 - 3.3% - 1.3k -
Physics and Astronomy #74 - 4.6% - 673 -
Psychology #95 - 4.4% - 3.5k -
Social Sciences #113 #107 5.7% 5.1% 20k 209
Veterinary #29 - 2.6% - 255 -

What is each known for?

The keywords that describe each side's research, by fractional works in 2022-now and weighted toward what it does more of than the world.

Nigeria

▲ more of its work than of the world's◆ about the world's share▼ less than the world's
All 40 words, with their numbers
  1. Epidemiology6,992◆ 1.09×140 topics
  2. Sustainability6,209▲ 1.58×131 topics
  3. Environmental Impact6,008▲ 2.2×72 topics
  4. Education5,751▲ 2.1×146 topics
  5. Machine Learning5,438◆ 1.02×97 topics
  6. Sustainable Development5,257▲ 2.1×108 topics
  7. Globalization4,985▲ 1.58×173 topics
  8. Climate Change4,966◆ 1.14×127 topics
  9. Renewable Energy4,353▲ 1.87×61 topics
  10. Economic Growth4,324▲ 3.3×38 topics
  11. Oxidative Stress3,687▲ 1.39×63 topics
  12. Antioxidant3,412▲ 3.1×51 topics
  13. Development3,202▲ 5.6×23 topics
  14. Gender Equality3,084▲ 6.8×18 topics
  15. Corporate Governance2,913▲ 2.5×32 topics
  16. Risk Management2,754▲ 3.6×20 topics
  17. Curriculum Development2,746▲ 2.5×20 topics
  18. Antioxidant Activity2,743▲ 2.7×32 topics
  19. Nigeria2,734▲ 79×3 topics
  20. Information Technology2,674▲ 3.5×32 topics
  21. Medicinal Plants2,492▲ 4.0×21 topics
  22. Social Capital2,408▲ 2.9×20 topics
  23. Genetic Diversity2,394▲ 3.4×22 topics
  24. Antioxidants2,137▲ 3.0×17 topics
  25. Teacher Education2,125▲ 10×8 topics
  26. Toxicity2,107▲ 3.0×20 topics
  27. Governance2,098▲ 4.0×19 topics
  28. Quality Assurance2,067▲ 7.6×9 topics
  29. Fiscal Policy2,016▲ 6.2×11 topics
  30. Bioactive Compounds1,971▲ 4.9×15 topics
  31. Youth Unemployment1,884▲ 99×1 topic
  32. ICT1,763▲ 8.2×5 topics
  33. Institutional Quality1,723▲ 10×3 topics
  34. Inequality1,694▲ 4.6×18 topics
  35. Smallholder Farmers1,669▲ 4.9×6 topics
  36. Knowledge Economy1,451▲ 8.3×11 topics
  37. Mobile Phones1,415▲ 19×3 topics
  38. Inclusive Development1,410▲ 20×2 topics
  39. financial access1,397▲ 22×1 topic
  40. gender inclusion1,397▲ 22×1 topic

Sierra Leone

▲ more of its work than of the world's◆ about the world's share▼ less than the world's
All 40 words, with their numbers
  1. Epidemiology78▲ 1.48×79 topics
  2. Economic Growth68▲ 6.3×21 topics
  3. Climate Change66▲ 1.86×62 topics
  4. Globalization59▲ 2.3×48 topics
  5. Sustainability56▲ 1.76×50 topics
  6. Public Health45▲ 2.4×40 topics
  7. Environmental Impact41▲ 1.83×44 topics
  8. Fiscal Policy40▲ 15×6 topics
  9. Vaccine38▲ 7.3×10 topics
  10. Maternal Mortality37▲ 13×5 topics
  11. Governance36▲ 8.5×9 topics
  12. Pathogenesis36▲ 5.4×18 topics
  13. Immune Response36▲ 4.8×12 topics
  14. Community Health Workers35▲ 30×2 topics
  15. Health Inequalities34▲ 21×3 topics
  16. Poverty Reduction33▲ 19×5 topics
  17. Child Mortality32▲ 34×1 topic
  18. Health Systems32▲ 34×1 topic
  19. Institutional Quality31▲ 23×2 topics
  20. Economic Development30▲ 2.9×20 topics
  21. Risk Management30▲ 4.8×10 topics
  22. Infectious Diseases28▲ 6.4×8 topics
  23. Smallholder Farmers28▲ 10×5 topics
  24. Genetic Diversity27▲ 4.7×17 topics
  25. Regulation26▲ 3.8×11 topics
  26. Transmission26▲ 36×3 topics
  27. Outbreak24▲ 49×2 topics
  28. Adaptation24▲ 6.2×7 topics
  29. Ebola Virus24▲ 65×1 topic
  30. Reservoirs24▲ 65×1 topic
  31. ICT22▲ 13×3 topics
  32. Corruption22▲ 11×6 topics
  33. Gender Equality21▲ 5.8×11 topics
  34. Global Burden of Disease21▲ 6.4×4 topics
  35. Monetary Policy21▲ 6.6×7 topics
  36. Inequality20▲ 6.8×5 topics
  37. Global Health20▲ 9.6×4 topics
  38. Finance20▲ 8.1×3 topics
  39. Inclusive Development19▲ 33×2 topics
  40. Knowledge Economy18▲ 13×2 topics

Size is fractional works in the topics tagged with each word; colour is the word's share of the side's work against its share of the world's. Each word links to the topic it comes from most.

How has their output grown?

Nigeria has out-published Sierra Leone every year since 1980.

still counting20k40kNigeria40k in 2025Sierra Leone311 in 20251990200020102020

Fractional works per year.

Their share of all research

Growing output can still be a shrinking share, because all of science grows. Each line is a side as a percentage of every work published that year.

still counting0.25%0.50%0.75%Nigeria0.67% in 2025Sierra Leone0.0053% in 202519801990200020102020

Fractional works over all fractional works that year. How the balance of science has shifted.

How much of it reaches the world top 10%

The share of each side's works, year by year, that reached the world's 10% most cited for their field and year. The average of all institutions is 10.0% (why not 10%).

still counting5%10%15%Sierra Leone8.3% in 2025Nigeria4.6% in 2025200020102020

A year with under 1% of the side's peak output is left out: a rate over a handful of papers says nothing. The latest years are still being cited.

Who holds more of the world's best institutions?

A country's average quality and the number of institutions it holds at the very top can disagree, and both are worth knowing. The counts are nested: an institution in the top 50 is also in the top 100.

Nigeria 05 level0 Sierra Leone
  1. 0In the world top 500
  2. 0In the top 1000
  3. 0In the top 5000
  4. 0In the top 1,0000
  5. #51Elite capacityrank among 204 countries#51

Institutions ranked on research quality, 2022-now. Elite capacity counts a country's institutions by their worldwide rank, weighted so a place at #1 counts for more than one at #480.

Which publishes more research, Nigeria or Sierra Leone?

Nigeria publishes 122.4× as much research as Sierra Leone in 2022-now (134k against 1.1k fractional works).

Whose research has more impact, Nigeria or Sierra Leone?

6.6% of Sierra Leone's research reaches the world's top 10% most cited, against 4.9% for Nigeria.

Is Nigeria or Sierra Leone growing faster?

Output in 2022-25 was +104% against 2018-21 for Sierra Leone, and +22% for Nigeria.

Which has more open access research, Nigeria or Sierra Leone?

70% of Nigeria's research is free to read, against 68% of Sierra Leone's.

Which has more world-class institutions, Nigeria or Sierra Leone?

Nigeria holds 0 of the world's top 100 research institutions and Sierra Leone 0; in the top 1,000 it is 0 against 0.

Which institutions lead in each country?

The highest-ranked institutions on each side on research quality, 2022-now. The percentage is each institution's own top-10% rate: the share of its works that are among the world's 10% most cited for their field and year. Every figure stands alone, so they do not add up to 100%.

Nigeria

  1. 1Covenant University7.9% top 10% · 1.6k works
  2. 2Lead City University4.8% top 10% · 1k works
  3. 3Adekunle Ajasin University5.6% top 10% · 1k works
  4. 4Redeemer's University8.4% top 10% · 599 works
  5. 5University of Lagos5.2% top 10% · 3.6k works
  6. 6University of Ibadan6.0% top 10% · 5.8k works

Sierra Leone

  1. 1University of Sierra Leone5.1% top 10% · 501 works
  2. 2Njala University6.9% top 10% · 307 works
  3. 3University of Makeni5.7% top 10% · 66 works
  4. 4Sierra Leone Agricultural Research Institute7.9% top 10% · 73 works

The number is the rank inside the country. The track on each row is the top-10% rate; the tick is the average of all institutions, 10.0% (how it is set): teal above it, red below. The ranking is the quality score, which compares the rate with what each institution's own topics predict and adds a small reward for size, so the rates do not fall in order.

Who are the top researchers on each side?

The most cited researchers on each side, among those ranked.

Nigeria

  1. 1 Michael Ekholuenetale #7,006 worldwide 69k citations · 215 works
  2. 2 Olayinka Stephen Ilesanmi #10,324 worldwide 161k citations · 355 works
  3. 3 Mu’awiyyah Babale Sufiyan #10,737 worldwide 123k citations · 106 works
  4. 4 Oye Gureje #14,357 worldwide 94k citations · 694 works
  5. 5 Aminu Shittu #16,229 worldwide 34k citations · 108 works

Sierra Leone

  1. 1 Haja Ramatulai Wurie #161,092 worldwide 2.4k citations · 68 works
  2. 2 Amara Jambai #176,221 worldwide 3.4k citations · 97 works
  3. 3 Rashid Ansumana #239,551 worldwide 4.4k citations · 163 works
  4. 4 Abdul Salami Bah #270,549 worldwide 111 citations · 29 works
  5. 5 Augustus Osborne #296,042 worldwide 4k citations · 162 works