In London, especially, new agencies come and go. But one launch this week catches the eye: OneFifty, which is led by former Brands2Life digital execs Alex Pearmain and Katie Buckett.

The duo's exit from Brands2Life attracted plenty of agency interest, with Hope&Glory ultimately backing the new firm via a minority stake. That is probably because Pearmain, formerly O2's first head of social media, and Buckett are focusing on a fairly specialised set of skills — data and behavioural modelling — and bring attractive insight into such fashionable areas as social media, influencer marketing and analytics.

You would be hard-pressed to find a PR agency these days that doesn't claim similar expertise, but at least one client believes OneFifty's approach is relatively unique. Telefonica director of communications and reputation Nicola Green has already hired the firm to help it prove the value of its communications spend, and believes its offering is considerably more specialised than existing partners like Blue Rubicon and Hope&Glory.

"I haven’t seen it with other agencies at the moment," says Green, noting that OneFifty has developed a scorecard approach that allows her to link key business metrics — such as customer satisfaction and employee retention — with her communications and digital marketing. "I think they do offer something different, in the fact that they are very data led."

For observers attuned to the cutting edge of digital analytics, Telefonica's use of OneFifty may sound fairly straightforward. But it probably represents the kind of shift that corporate communicators are still grappling with. "They are helping me work out what work we are doing well, what we should continue doing and what we should stop doing, to keep utilising our budgets as well as possible," says Green. "This will get bigger over time as more and more people start questioning budgets."

Green believes that many companies, and agencies, still struggle to grasp the nettle when it comes to accurate measurement of their public relations activity, with dubious metrics like AVEs continuing to retain an appeal. "Some people are quite happy with those measurements, and not everyone has pushed back."

Instead, Green believes that a more rigourous approach will expose whether the work really is good or not. "I think that’s why people haven’t adopted it," she notes. " How do you work out what is the right or wrong thing to do, without purely going on gut feeling? Comms should be supporting business in the right way, not just doing things we want to be doing."

For Telefonica that means, specifically, coming up with metrics that Green's board can support — "we have to make sure we have buy-in from the board for all stages" — and are clearly linked to overall business metrics such as customer satisfaction, staff retention, brand consideration and financials.

For firms like OneFifty, meanwhile, the challenge will likely be scaling its approach for more clients and ensuring that its offering is not 'too' esoteric for buyers of agency services. Unsurprisingly, Pearmain believes companies are finally ready for a data-led approach that sits across various marketing channels.

If he is right, it would suggest a gap in the market, akin to what we saw when the last wave of social media agencies launched around seven years ago. "I do think there’s a gap in the market," agrees Ogilvy PR UK MD Marshall Manson. "Often new firms spy opportunities and have innovative solutions that the big guys haven’t gotten around to yet."

"You’re starting to see new organisational models and a willingness to buy outside the traditional categories," adds Pearmain. "The data skills don’t exist within PR agencies. There are a lot of good people but they are insufficiently concentrated in agencies. We want to work with data scientists who want to work in marketing and social insight. "

Finding those people, and convincing them to work at an agency rather than, for example, Google, will be another challenge. But if OneFifty, and similar firms elsewhere, can convince enough clients of their utility, that will only spur more rapid change among bigger agencies. And that, ultimately, can only help communicators justify their budgets and prove their worth in a more credible manner.