Making waves with response radio

Direct response on radio has traditionally been something of a black art. Some advertisers complain that they can’t get radio advertising to generate sufficient enquiries, while others are quite clearly using it to make a fortune but won’t – understandably – reveal how they do it and what sort of response they get.

The new report Direct Response Radio, funded by Classic FM, GWR, BT and the Direct Marketing Association, offers the advertising and marketing community a first chance to look in detail at how radio makes the telephone ring.

It’s important to say this is only a first phase: it looks purely at response to BT special numbers (such as 0800), and measures short-term response rather than longer-term effects. A follow-on study is being planned which will look at other issues, such as creativity.

In terms of method, the study monitors response to more than 4,000 ads over the course of three weeks, on national and local radio. For each brand, BT logged the rate of telephone enquiries around transmission time.

So what does the study tell us? For a start, it answers the question “What is the average rate of response to a radio campaign?”. The magic number is calculated as 0.15 per cent – though this is of course a purely theoretical average across all the campaigns, some of which worked far less efficiently than others (response is calculated as the number of incremental calls registered by BT, divided by the number of people estimated to be listening at the time).

Some ads also worked far more efficiently than others: one campaign, the best-performer, registered a response rate of over ten per cent. Regrettably, BT client confidentiality means we cannot know which advertiser achieved this astonishing rate of response.

As shown in figure 1 (opposite top), there is quite a gap between the response rates for the top ten ads and the rest.

Figure 2 (opposite centre) shows the pattern of response according to how soon an ad is repeated. The clear implication is that ads which are repeated within the hour show a significantly higher response efficiency. This makes sense, as radio listeners who are interested in the offer are not always in a position to note the number or make the call.

In terms of response across the day, there are some very interesting findings, as shown in figure 3 (opposite bottom). Response efficiency is very low at the beginning of the day, and only begins to pick up around lunchtime.

This immediately puts a question mark against the wisdom of using morning airtime, when the radio audience is at its highest level on most stations. The report suggests that “the best strategy would involve building a brand and establishing an offer through the day, and achieving response by spreading the campaign into the evening”.

This certainly tallies with the experience of some current advertisers, whose pattern of activity suggests there are broader factors involved: for example, one of the most successful radio-advertised brands, the Carphone Warehouse, uses a disproportionately large amount of morning peak airtime with conspicuously successful results at response level.

The study also looks at response by day of week (weekends are best) and length of spot (ten-second spots are best, although there is an effect in here from the 60-second spots which many of the tens run with), as well as by trade sector.

In summary, the study provides some of the first-base answers which media planners are looking for on direct response; meanwhile there are plenty more questions to ask.