According to a recent study, children under the age of 16 years make up less than 1% of participants in national NHS patient surveys. The study published online in the Archives of Disease in Childhood.
But the issue is particularly important as young adults who are asked about their experiences of the NHS, are less satisfied with the care they receive than older adults, say the authors.
In 2010 the Kennedy Report concluded that services for children and young people receive disproportionately lower priority in the NHS and that these often provide mediocre care.
Current government policy places a great deal of emphasis on patient feedback as a spur to improving the quality of care.
The researchers reviewed 38 national surveys undertaken between 2001 and 2011, covering all aspects of NHS care.
Patients under the age of 16 were included in only one of these surveys, equivalent to just 0.6% of more than 10 million respondents since 2001, and none since 2004.
Most of those aged 16 to 24 were positive about their experience of the NHS, but they were less happy with the care they received than older adults.
Around 80% of young adults said they were happy with the care they received in emergency departments in 2008 compared with 89% of older adults.
Similarly, the 2009 Inpatient Survey showed that 86.5% of young adults were happy with the level of care they received. But this compares with almost 93% of older adults.
As for primary care services, 83% of 18 to 24 year olds said they were satisfied with the level of care they received, compared with 90% of older adults.
Young people also tended to say they felt less involved in their care, had less confidence and trust in their doctor, and felt they were treated with less respect and dignity than older people.
"Despite the current focus on services for young people and the importance of patients' views in improving services, the voice of under 16s is not included in most national surveys," conclude the authors.
And they go on to say: "Failure to listen to the views of under 16s is not an issue confined to England. We are not aware of any other country that has conducted systematic national surveys which look at young people's experience of healthcare."
They conclude: "As our data show, NHS services are often good at listening to young people and making them feel involved in their care during individual consultations. However, at the national policy level, there is a clear gap between our findings and the stated aims of professionals and policy makers to listen to young people."