Disparities in the geographical distribution of authorship between invited and peer reviewed papers

Fifty issues of the British Medical Journal (BMJ), The Lancet, The British Journal of Psychiatry and Psychological Medicine were scrutinized. Papers were designated as invited or peer reviewed and the geographical location of the first author was recorded. For UK-based authors, the latitude and longitude of the host institution was noted and was allocated to one of the UK regions. Of invited papers 805 of 1227 (66%) were by UK-based authors compared with 1442 of 2896 peer reviewed papers (50%), odds ratio 1.92 (95% CI 1.67-2.21) with a similar pattern prevailing in each of the four journals. Within the UK, authorships of invited versus peer reviewed papers showed a preponderance of invited authors based in southeast England, odds ratio 1.30 (95% CI 1.09-1.56). For individual Journals, the Lancet and the British Journal of Psychiatry showed fewer regional disparities in authorship than the BMJ and Psychological Medicine. These disparities may lead to nationalism and parochiality in the content of invited papers. Journal editors may wish to review selection practices for authorship of invited papers.