There were more than 1,400 complaints filed about the care at the district’s hospitals last year, latest figures show.
Mid Yorkshire Hospitals Trust was the third most complained-about in the country, according to a report by the Parliamentary and Health Service Ombudsman.
In 2013–14, there were 1,405 written complaints about Pinderfields, Pontefract and Dewsbury hospitals.
Some 67 complaints were referred to the ombudsman, which carried out 15 investigations.
But only one was upheld by the ombudsman, which investigates complaints when patients feel hospitals have failed to resolve the problem.
The ombudsman report said the top three reasons for complaints were poor communication, errors in diagnosis and poor treatment.
Other reasons included staff attitude, no apology when things went wrong and unnecessary delays in treatment, the report said.
Mid Yorkshire said people with complaints should speak to the ward manager in the first instance if they were an inpatient. People with complaints about outpatient clinics should speak to the doctor or receptionist.
Sally Napper, Mid Yorkshire’s chief nurse, said: “When patients feel they can’t do this our Patient Advice and Liaison Service (PALS) can step in to help patients get the answers they need.
“PALS actively promotes its service so patients know when and how to raise concerns. The service works with patients and their families as well as colleagues in wards and departments to resolve problems quickly.
“Earlier this year we opened a PALS drop in centre at Pinderfields Hospital that offers people the opportunity to have face-to-face contact with the team without the need for an appointment.”
Barts Health NHS Trust in London was the most complained-about trust in the country, with some 2,451 written grievances in 2013-14.
NHS complaints made last year:
Bradford Teaching Hospitals NHS Foundation Trust: 553
Leeds Teaching Hospitals NHS Trust: 1,066.
Mid Yorkshire Hospitals NHS Trust: 1,405.
Sheffield Teaching Hospitals NHS Foundation Trust: 949.
The Rotherham NHS Foundation Trust: 595.
Barnsley Hospital NHS Foundation Trust: 279.