NHS England receives 480 written complaints a day, with hospital doctors and surgeons among those bearing the brunt of patients’ frustrations, new figures show.
There were almost 175,000 written complaints about the health service in 2013-14 - the equivalent of 3,300 a week - according to the Health and Social Care Information Centre.
Almost half of complaints about hospitals and community health services were against medical professionals, including doctors and surgeons, followed by around 20 per cent against nurses, midwives and health visitors.
Complaints were made over a wide range of issues, from the cancellation of appointments and the attitude of staff to transport, privacy and dignity and consenting for treatment, across areas such as ambulance services, community hospitals, NHS Direct and mental health services.
But the number of annual complaints could be the tip of the iceberg when it comes to people having a poor experience through the NHS, a health watchdog said.
Healthwatch England claimed there could be around 500,000 incidents of poor care or patient dissatisfaction that have gone unreported over the last two years.
It suggested that more than 60 per cent of patients who received poor care or witnessed a friend or relative being looked after badly did not complain about it.
HSCIC figures revealed there was 174,872 written complaints against NHS England in 2013-14 and 162,019 the previous year, though the centre said the numbers were not directly comparable because of differing numbers of GP surgeries giving data on complaints this year.
There were 114,300 written complaints against NHS hospitals and community health services over the last year, a 4.6 per cent rise from the 109,300 in 2012-13 - the equivalent of an extra 96 complaints a week.
The biggest increase in complaints across professions was against paramedics and ambulance crews - 5,700 in 2013-14 compared with 4,440 the previous year, a rise of 28.5 per cent.
But medical professionals - including hospital doctors and surgeons - received the highest number of complaints, with 52,100 (45.6 per cent).
This was followed by nurses, midwives and health visitors, who had 24,800 complaints (21.7 per cent).
There were 52,300 complaints relating to “all aspects of clinical care”, with 13,300 about the attitude of staff and 11,500 over communication and information provided to patients.
There were also 3,940 complaints about transport, including ambulances, an increase of 43.4 per cent on 2012-13.
Over the last year, there were also 60,600 written complaints about family health services, which include GPs and dentists.
Some 24,400 complaints were made about medical services, followed by 22,600 about general practice administration and 6,970 about dental services.
Around 22,200 complaints were of a clinical nature, and 13,300 related to communication with patients or general staff attitude.
Anna Bradley, chair of Healthwatch England, suggested the reported number of written complaints did not fully reflect the levels of poor care patients were receiving.
The organisation said a YouGov survey of 1,676 adults in England showed that over the last two years around 30 per cent of people had received poor care themselves or seen a relative or friend receive poor care from a health or social care service.
But of these, 61 per cent did not complain about it, and the health watchdog suggested potentially 250,000 people a year were failing to get the treatment and care they expected and felt they could not make their voices heard.
Ms Bradley said: “The report out today really is just the tip of the iceberg when it comes to complaints about health and social care services in this country, with the reported figures significantly underrepresenting the true number of incidents of poor care.
“The need to improve the way the complaints system operates is well documented and we have been working with government to simplify the often baffling process for patients and their families.
“But for things to work properly, health professionals clearly need to do more to make people feel less intimidated about making their voices heard.”