Fig 1.
Trend of the overall publication output in science.
Total publications (a) and yearly percentage increase (b) on WoS excluding ESCI index (red), Scopus (blue) and PubMed (green) databases for all scientific publications published between 1998 and 2018. Lines in (a) are fitted quadratic trend lines. Lines in (b) connect individual data points. Search term used in WoS was: “PY = 1998–2018”. In Scopus: PUBYEAR AFT 1998. In PubMed 1998:2018[dp]. Searches were refined for articles and reviews only. (c) shows total publication output in WoS excluding ESCI index (search term “PY = 1998–2018”) refined for articles and reviews (orange); articles, reviews, book chapters, proceedings papers and book reviews (purple) or all scientific literature listed in WoS (pink). (d) shows yearly percentage increase for the total publication output using the data shown in (c).
Table 1.
Investigated fields in the life sciences.
The 37 fields for which GGTs were calculated and inflation adjusted trend analysis performed. Fields are classified into different sections. The classification used is non-stringent and merely used to reflect the potential of GGT over a variety of disciplines in the life-sciences.
Fig 2.
a) The publication trend (blue circles) for articles and reviews (right-axes) and GGT (red squares; left-axes) for the search string: TS = (vaccin*) AND PY = (1970–2020) on WoS excluding the ESCI index. b) The absolute number of publications (right y-axes; circles) and relative yearly percentage increase (left y-axes; triangles) in total publications reported on WoS using all indexes (brown) of WoS or all but the ESCI index (black). Spikes in the GGTs and growth trends indicate the inclusion of keyword searches in abstracts in 1991 (a) and the inclusion of the ESCI index in 2015 (b) respectively.
Fig 3.
Trend analyses of publication trends derived from reviews.
Fields analysed are: (a) celiac disease [17, 21], (b) Malaria [23], (c) Giardia [22], (d) sensor arrays [1], (e) microbiome [6] and (f) climate change [5]. All searches were conducted using keyword searches in the field section of WoS (dark colours) or PubMed (light colours). Search terms used were identical to those specified in the articles (see S1 File for specifications). The GGTs (dark and light red squares) are plotted on the left y-axes. The number of publications per year (dark and light circles) are plotted on the right y-axes.
Fig 4.
Trend analyses of publication trends on various life science fields.
a) GGTs for the fields Alzheimer’s, microplastics and machine learning. b) GGTs (squares, left y-axes) and publication trends (circles, right y-axes) for the field microbiome using either a title search (red) or a field search (blue). c) GGTs (squares, left y-axes) and publication trends (circles, right y-axes) for the fields NAFLD and obesity. d) GGTs (red squares; left y-axes) and publication trends (blue circles; left y-axes) for melamine research. e) GGTs (red squares; left y-axes) and publication trends (blue circles; left y-axes) for the field avian flu (H5N1). f) GGTs for various omics techniques. All field searches were conducted in WoS excluding the ESCI index. Search strings and raw data used are given in the S2 File.
Fig 5.
Alternative growth rate corrections.
(a) shows total publication output for the five main research areas specified in WoS and (b) shows the growth rate calculated for those areas over the 2018–1998 period. (c) shows the total publications for WoS research categories (two categories per research area). (d) shows the growth rate calculated for those categories over the 2018–1998 period. Panel colours are matched to the research areas indicated in (a). The ESCI index was excluded for all analyses. (e) Average GGTs for the microplastics field using all literature or the WoS research category “environmental sciences” as the PO. (f) Annual GGTs for the field microplastics using all literature or the WoS research category “environmental sciences” as the PO.
Fig 6.
a) Total yearly technology patent output (blue circles; right y-axes) and yearly technology patent output growth rate percentages (red squares, left axes). b) GGTs for food chemistry patents (red squares) and environmental technology patents (blue squares). Patent data was downloaded from the EPO database.