Theresa May, the then home secretary, kept a relatively low profile in newspaper coverage dominated by pro-Leave articles in the run-up to the EU referendum, according to new research.

The prime minister may have backed a vote to remain in the EU, but she did not even make the top 10 most cited politicians in a survey of UK press coverage in the four months leading up to the 23 June poll by the Reuters Institute for the Study of Journalism, accounting for just 1% of mentions.

Conservative men dominated the coverage, as did reports backing a vote to leave the EU. The detailed study of 2,378 articles for the report, UK press coverage of the EU Referendum, found 41% were pro-Leave, while 27% were pro-Remain. Once reach and circulation figures were factored in, 48% of all articles were pro-Leave with six out of the nine national newspapers surveyed in favour of Brexit.

Jeremy Corbyn was the only Labour MP in the top 10 of those cited. However, as the eighth most quoted politician, he was cited in just 3% of articles in the survey of coverage dominated by Conservative men, including David Cameron, Boris Johnson and George Osborne although not all the coverage of these men was positive.

Priti Patel, pro Leave Conservative MP, received more coverage than Corbyn and was the only woman in the top 10, joined by Brexit campaigner and Labour MP Gisela Stuart, Andrea Leadsom, Nicola Sturgeon and May in the top 20.

The research delved into the topics covered and found a surprising emphasis on the personalities involved and the contest rather than the issues.

The economy was the biggest single issue covered in articles, followed by sovereignty and migration. The economy was cited in both pro-Leave and Remain articles, but sovereignty and migration skewed heavily to pro-Leave articles.

Pro-Remain articles tend to use a negative tone, with pessimistic forecasts of a post-Brexit future, however, as pro-Leave articles adopted a more positive tone, on the economy but more strongly around the issues of migration and sovereignty.

Dr David Levy, director of the Reuters Institute and one of the report’s authors, said: “The research reveals a picture of highly polarised press coverage, reliant on a narrow range of voices, and where coverage was relatively more focused on the contest itself and personalities than any of the complex issues at stake.

“In that sense, in spite of some notable exceptions, the press was generally better at reinforcing the views of decided voters than in giving undecided voters, seeking broad facts and high-quality information, the evidence to make up their own minds.”

With only the Guardian, Financial times and Mirror pro Remain, the research found that the Times published more pro Leave than pro Remain articles in the final week of campaigning and after the newspaper advocated a vote for Remain.

The newspaper’s readership was also more pro-Remain than the newspaper was, according to the research.

In contrast, readers of the Mirror were found to be more pro-Leave than their newspaper, according to the accompanying research by YouGov.

While the Express and the Mail were the most partisan, the study found that the pro-Remain papers became more so in their reporting of the EU referendum in the last week.

The study, which was produced jointly with PRIME Research, focused exclusively on newspapers rather than broadcasters. A report by the Electoral Reform Society published earlier this month criticised broadcast coverage and made several recommendations to improve the way referenda are conducted in the future.

It also studied Tuesdays and Saturdays and so did not cover the difference between the Mail on Sunday or Sunday Times and their daily sister titles.