The firm predicts that the field will continue to grow this year at “low double-digit rates”, despite the onset of recession. The forecasts come from PQ Media’s Word-of-Mouth Marketing Forecast 2009-2013.

The growth in measurement is keeping pace with growth in total spending on WOM marketing, which was up 14.2% in 2008 to $1.54bn, and is expected to grow by 10.2% this year.

In its analysis of the results, PQ Media said WOM marketers are calling for better measurement, and demand is driving the development of more effective metrics.

The company said: “Although more leading brands are accepting WOM, they are demanding data to justify their spending. Marketers are requesting research that extends beyond anecdotal information about online conversations and consumer attitudes. They expect proof of return on investment, and WoM research companies are developing new metrics to address these demands.”