A Which? study of NHS walk-in centres, which offer advice and treatment for minor complaints, has found that they are not providing and adequate or safe service.

The investigation found that staff in several centres did not carry out complete assessments of patients, leading to "shockingly superficial" treatment in some cases.

A health department spokesman said all 36 centres in England were being evaluated, also noting that since the study a computer-supported "triage" system had been introduced.