Appeal decided that the trust had breached the 2002 contract for junior doctors because their hours and rest periods had been underestimated by commercial software over some years. The case will affect other NHS employers and substantial arrears will be due. Risks to patients The period in August where there was a large changeover of hospital staff has sometimes been dubbed the "killing season" (due to a perception that there is an associated rise in the number of patient deaths). In 2009 research looking at emergency admissions to hospitals in England established that a small but statistically significant increase in patient mortality was occurring during August. The limited data was collected retrospectively over an 8-year period, comparing two week-long blocks (one week prior to commencement, one week post commencement). The methodology meant that drawing firm conclusions was unwise with correlation not implying causation. In the month when junior doctors start working - when other factors are adjusted for patients had a 6% increase in mortality. For patients admitted as an emergency who were not requiring surgery or suffering from cancer, the mortality rate increased by 7.86%. Other concerns have been raised regarding mortality following admission to hospital at a weekend. A research paper published in 2012, looked retrospectively at data from 2009; the study observed an increase in 30-day mortality for people admitted to hospital on Saturday and Sunday, compared to mid-week days. The risk of dying in a hospital on Saturday or Sunday was actually less than on a weekday. The data in the study did not enable the authors to describe the cause of this so-called weekend effect. Subsequently, there has been considerable speculation around whether the availability of consultants was a factor. The authors of the paper have also openly criticised the conclusions drawn by the government and popular media on the paper, saying that to draw such conclusions as to associated decreased weekend staffing levels to increased mortality at 30 days post-admission would be "rash and misleading". Health Education England produces reports on NHS trusts under “enhanced monitoring” by the General Medical Council, because of concerns from trainees. 20 of these were analysed by the Health Service Journal in 2020. Bolton NHS Foundation Trust and Barking, Havering and Redbridge University Hospitals NHS Trust featured prominently. Reports included consultants leaving junior doctors with insufficient support, bullying, reluctance to report concerns and IT problems. It has the power