West Midlands Ambulance Service complaints double in three years
Complaints to the West Midlands Ambulance Service have more than doubled since 2010.
The figures from the Health and Social Care Information Centre showed 222 written complaints were made to the service in 2010-11, compared with 471 in 2012-13.
A spokesman from the service said social media had made it easier for complaints to be generated.
He added that the service had 900 compliment letters in the same period.
"In a sense we encourage it by giving people the opportunity to comment on Facebook and Twitter," said the spokesman.
"Some of those more informal comments then become formal complaints.
"Our website also encourages people to have their say on the service so makes it easier for complaints to filter through."
Sandy Brown, director of nursing and quality at the West Midlands Ambulance Service NHS Foundation Trust, said the figures needed to be "put into perspective".
"Over the last 12 months, the trust has actively been promoting patient feedback... last year (we) received over 960,000 emergency calls and roughly 1,000,000 non-emergency patient transport service journeys.
"That equates to one complaint for every 4,165 calls, 0.02% per year, which is very low."
The trust covers Shropshire, Herefordshire, Worcestershire, Warwickshire, Staffordshire and the Birmingham, Solihull and Black Country areas.