To examine the effect of the 24-h doctors’ strike on 21 June 2012 on hospital activity in English NHS hospitals.

Retrospective descriptive study of inpatient, outpatient and Accident and Emergency (A &E) activity in NHS hospitals over the strike period.

All English NHS hospitals.

Patients admitted to hospital, patients with outpatient appointments and A &E attendances over a three-week period (from 11 to 29 June 2012), excluding weekends and spanning the strike day.

Numbers and percentage change of inpatient admissions (elective and emergency), day surgery cases, outpatient appointments cancellations, A &E attendances and in-hospital deaths on the day of the strike compared with patient activity on the Thursday before and the Thursday after the strike week.

There were a total of 795,267 admissions, 5,602,971 outpatient appointments, 356,645 outpatient cancellations (by NHS provider), 4,470,208 outpatients seen by medical staff, 986,322 A &E attendances and 13,857 in-hospital deaths over the three-week period. Compared with the non-strike period, on the day of the strike, emergency admissions fell by 2.4% while the elective admissions decreased by 12.8%. There was a 7.8% drop in the number of outpatients seen by medical staff on the day of the strike and a 45.5% increase in the number of cancelled appointments by NHS hospitals, while A &E attendances dropped by 4.7%. The impact of the strike across regional Health Authorities in England was varied. The North West Health Authority was affected the most while the least affected Health Authorities were the South West, East of England and South Central.

The 24-h doctors’ strike in England on 21 June 2012 significantly affected the provision of healthcare by NHS hospitals. We observed regional variations on NHS service levels on the day of the strike.