Evaluating the scientific output: Bibliometric indicators

The Journal Impact Factor is the average number of times articles from the journal published in the past two years have been cited in the JCR year.

Quartile rankings are derived for each journal in each of its subject categories according to which quartile of the IF distribution the journal occupies for that subject category.

The databases that offer this indicator are:

Incites JCR (Incites Journal Citation Reports)
Scopus 
SJR (Scimago Journal & Country Rank) 

Quartiles are useful when applying for grants and assessment such as (National Agency for Quality Assessment and Accreditation of Spain, ANECA) or (Catalan University Quality Assurance Agency, AQU Catalonia)
Quartiles are also useful when deciding best journals to publish.

SJR (SCImago Journal Rank) indicator: It expresses the average number of weighted citations received in the selected year by the documents published in the selected journal in the three previous years, --i.e. weighted citations received in year X to documents published in the journal in years X-1, X-2 and X-3.

SNIP (Source Normalized Impact per Paper) measures contextual citation impact by weighting citations based on the total number of citations in a subject field.

The databases that offer these indicators are: Scopus and SJR (Scimago Journal & Country Rank)  

Measures average citations received per document published in the serial.
CitesScore FAQs. 
The databases that offer this indicator are: Scopus and SJR (Scimago Journal & Country Rank)  

The Immediacy Index is the average number of times an article is cited in the year it is published.

• The journal Immediacy Index indicates how quickly articles in a journal are cited.
• The aggregate Immediacy Index indicates how quickly articles in a subject category are cited.

The Immediacy Index is calculated by dividing the number of citations to articles published in a given year by the number of articles published in that year.
The databases that offer this indicator are: Incites JCR (Incites Journal Citation Reports)

A journal's Eigenfactor score is our measure of the journal's total importance to the scientific community.

The databases that offer this indicator are: Eigenfactor and Incites JCR (Incites Journal Citation Reports)

Main characteristics:

• covers a period of five years
• measures the importance of scholarly journals within the scientific community. 
• a metric that rates journals on the basis of citations but gives higher weight to those citations coming from more influential journals.
• this indicator is more qualitative than quantitative
• Eigenfactor assigns journals to a single category
• self-citations are not included.
• Eigenfactor scores and article influence scores rank journals much as Google ranks websites.

The h index expresses the journal's number of articles (h) that have received at least h citations. It quantifies both journal scientific productivity and scientific impact and it is also applicable to scientists, countries.