I hear a tremendous amount of tosh spoken about the commercial measurement of PR results. Here, the InBev CMO asks the question that people want an answer to: "How does it sell more beer?"

If you cut to the chase it is dead simple in principle.

Compare it to the language of advertising - buy the impressions you want to make, and correlate the impact of the ad with sales at the checkout. Using services such as Neilsen digital ad ratings, you can optimise and tweak the reach as you go, and measure resonance of the campaign in particular. 

As a former marketing chief, I recognise the safety in this; I can speak to the chief exec and make a cast iron promise about reach when I ask for money.

How did the advertising agencies get here? It was pretty natural (although hard work) - advertising emerged from from the sales function. PR didn't. 

So as a PR agency leader, here is my cure all - it's simple to say, but hard to do. 

Get the business data and study it.

PR firms need to work with clients to get historical data from campaign effectiveness, and use that to inform future predictions of sales effectiveness. 

Over time, the predictions will get more accurate - and that is all that CMOs need. But we need to start today.

Clients have a wealth of historical data; there are some key metrics you can use to compare success, such as year over year  or  qtr over qtr sales results for the period, success vs others in the market. If there is additional data from customer services; "where did you hear about us,"; brand reputation surveys, attraction and recruitment statistics. Businesses have this data, often it's provided to the ad agency - so you can just ask for the same treatment. You can even ask the advertising agency for their measurement metrics. 

Then overlay this with the traditional measurement that PRs normally do: Reach, OTC, AVE, resonance, engagement, social sharing, message accuracy, influencer engagment, tier one and tier two coverage etc.. 

With a solid historical data set that shows a firm correlation between the classic PR measurement dimensions and business data, we can say with a fair amount of certainty that the next time we do x,y or z campaign the results will fall within a particular range. 

The Ad guys have done a tremendous job of making a vague and complex assessment of the world at large seem scientific. Econometrics does work, but it isn't an exact science. Some ads catch the public's imagination, some don't - but all media agencies make fairly specific predictions about the reach they will have.

PR can do the same. We just need to invest our time with our clients to ask the questions, collect the data and analyse the results.

Data? Analysis? Statistical correlations? PR? 

Doing this work is scary - and what if the results aren't what we want to hear?

Well, I for one don't want to do something with my time that doesn't make a difference. My gut instinct is that this works - I've seen the transformational effect that a great PR campaign can have on clients' businesses, so I'm happy to invest the time to ask the question...

Who's in?