Research Intensity Index (RII)
Research Intensity Index measures the average research output per researcher within each university. It is calculated by dividing the total number of documents produced by an institution by the number of authors affiliated with that institution. In simple terms, RII shows how productive the average research-active staff member is. A higher value means that, on average, each researcher contributes more published work, while a lower value points to lower average output per researcher. This moves attention away from total volume alone and towards researcher-level efficiency.
Formula
RII = Number of Documents / Number of Authors
Usefulness
- Allows fairer comparison across universities of different sizes.
- Shows average output per researcher.
- Helps separate scale from efficiency.
Strengths
- Controls for differences in staff size.
- Useful for comparing large and small institutions.
- Easy to interpret as output per researcher.
Limitations
- Does not adjust for institutional age.
- Can be affected by very small author counts.
- Does not account for publication quality.
Ranking table
| Overall Rank | Block Rank | Institution | Block | RII(Docs/authors) | Number of Documents | Number of Authors |
|---|---|---|---|---|---|---|
| 1 | 1 | Edo University Iyamho | State | 7.683 | 484 | 63 |
| 2 | 2 | Bayelsa Medical University, Yenagoa | State | 5.938 | 285 | 48 |
| 3 | 1 | Western Delta University, Oghara | Private | 3.441 | 117 | 34 |
| 4 | 1 | Fed. University of Petroleum Res. | Federal | 3.092 | 909 | 294 |
| 5 | 3 | Akwa Ibom State University | State | 2.742 | 828 | 302 |
| 6 | 2 | Federal University, Otuoke | Federal | 2.687 | 489 | 182 |
| 7 | 4 | University of Cross River State | State | 2.574 | 726 | 282 |
| 8 | 2 | Topfaith University, Mkpatak | Private | 2.500 | 60 | 24 |
| 9 | 5 | Niger Delta University Wilberforce Island | State | 2.381 | 1,257 | 528 |
| 10 | 3 | Wellspring University, Evbuobanosa | Private | 2.375 | 76 | 32 |
| 11 | 4 | Benson Idahosa University, Benin City | Private | 2.252 | 340 | 151 |
| 12 | 3 | University of Benin | Federal | 2.206 | 9,534 | 4,321 |
| 13 | 4 | University of Port-Harcourt | Federal | 2.193 | 6,497 | 2,962 |
| 14 | 6 | Rivers State University | State | 2.150 | 2,279 | 1,060 |
| 15 | 5 | University of Uyo | Federal | 1.954 | 3,673 | 1,880 |
| 16 | 7 | Delta State University Abraka | State | 1.870 | 3,437 | 1,838 |
| 17 | 8 | Ambrose Alli University | State | 1.817 | 1,319 | 726 |
| 18 | 6 | University of Calabar | Federal | 1.804 | 6,836 | 3,790 |
| 19 | 9 | University of Delta, Agbor | State | 1.752 | 247 | 141 |
| 20 | 10 | Delta University of Science and Tech. | State | 1.751 | 429 | 245 |
| 21 | 5 | Igbinedion University Okada | Private | 1.716 | 453 | 264 |
| 22 | 11 | Dennis Osadebay University, Asaba | State | 1.543 | 233 | 151 |
| 23 | 12 | Ignatius Ajuru University of Education | State | 1.515 | 206 | 136 |
| 24 | 7 | Admiralty University Ibusa | Federal | 1.280 | 32 | 25 |
Note: Ranking is based on average research output per author. Data were extracted from the Scopus database and were accurate as of 12 pm, 9 February 2026.
Derived from the doctoral research of Valentine Joseph Owan on university research performance in South-South Nigeria, University of Calabar, 2026.