"I don't think we do enough to support people who work in comms across the NHS," said Tiernan, who will leave his role to take up a new job as director of comms at the London Ambulance Service in August.
He set up NHScommsorg several years ago as a "way to support NHS communicators". The organisation now has a Facebook group with 1,200 members and about 7,500 followers on Twitter.
The unofficial network is "just an easy way for people to connect and share best practice", according to Tiernan. "If you work in some of the other professions, whether you are the medical director or the nursing director or whatever, there's a lot of support out there for them, for their professions; I don't think we have that for comms people."
He made his remarks during an appearance on a new podcast by NHS Elect, the health service’s training and resources arm, earlier this month.
Don't create apps for the sake of it
The comms chief also commented on the increasing popularity of apps, warning that people should take care not to duplicate time and effort by creating their own apps.
"We just need to be really careful about how much money we are spending and how much time is put into that because there are apps out there," he said.
"If you look at the NHS apps library – if something is already there, why would you want to create your own? I know it's lovely to have your own hospital logo or whatever it is on it, and maybe you do localise it a bit, but just think about how much time and money you’re spending and whether in the long term you can sustain it."
When it comes to social-media platforms such as Facebook, whose reputations have been damaged by 'fake news' scandals, NHS organisations have "a part to play" in rebuilding trust, Tiernan argued.
"The last thing we want is for people leaving in their droves from these platforms… we want to use them when we want to talk to people."
He added: "We can help by being good users of these platforms and telling good stories," stressing the importance of "quality over content."
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