Characteristics and quality of published animal research in the field of radiology

Background Animal research has played an important role in the field of radiology. Purpose To evaluate the characteristics and quality of published radiological animal research. Material and Methods A PubMed search was performed for radiological animal research articles (defined as studies using animal models with a radiologist as the first author) published in 1994, 2004, and 2014. The following information was extracted from each article: journal name, radiological subspecialty, imaging technique, animal species, number of animals used, number of authors, declared funding, country of origin, methodological quality, and ethical quality. Methodological and ethical quality of studies were assessed with seven-item (sample size calculation, animal age, animal sex, animal weight, inclusion and exclusion criteria, randomization, and blinded outcome assessment) and four-item (ethical review committee approval, anesthesia, pain control, and euthanasia) scales, respectively. Results The numbers of radiological animal studies markedly increased, from 91 in 1994 to 163 in 2004 and to 305 in 2014. One hundred and sixty-two (29.0%) articles focused on the neuroradiology/head and neck subspecialty, 233 (41.7%) used magnetic resonance imaging (MRI), 190 (34.0%) used mice, 254 (45.4%) used 10–30 animals, 297 (53.1%) had 4–7 authors, 392 (70.1%) were funded, and 222 (39.7%) were from the USA. Six of 7 methodological and 3/4 ethical quality items significantly improved over time. Conclusion The quantity and quality of radiological animal research has increased over the last two decades; however, methodological and ethical quality remains suboptimal.