Common sense tells us that the harder it is to reach and complete surveys with qualified respondents, the more costly and time consuming the research project will be. But, how do professional research firms assess the required level of effort in advance so that they can determine the most appropriate methodologies and provide reasonably accurate project estimates and schedules? They establish an estimated incidence rate.
Simply put, an incidence rate is the frequency of something occurring in a given population. Specifically in market research, prior to a project we estimate the number of people who, once we get them on the phone, will not qualify for the survey, or will refuse to participate. This estimate helps guide the cost of the project. If 4 out of 10 people, once we get them on the phone, qualify for and complete the survey, the overall incidence rate is 40%.
The more specific your audience parameters or “screeners” are, the lower the incidence rate will be, thereby increasing the required number of people to be called. For example, the chance of completing surveys with 200 mid-level IT managers in organizations larger than $20 million is much better than if those same IT managers must be located in the northeast and use a specific brand of servers. Hence, the second sample population would require more money and time to identify. In fact, the difference of only 10 percentage points in incidence rates translates into thousands of more contact names and dollars required.
In addition, the quality of the contact list has a big impact on the incidence rate. Obviously, using a company’s customer list to conduct a customer satisfaction survey will produce a much higher incidence rate than reaching out to prospects to conduct a market awareness study. And, of course, in-house lists that are highly targeted and frequently scrubbed perform better than lists acquired from outside sources.
Good research firms calculate the actual incidence rate for every study they complete. Then, when estimating an upcoming project for a client, they compare incidence rates for past studies that have similarities to the one at hand. They then factor in their experience with the market, the list source, the methodology (e-mail, phone, or mail), the subject matter, and so forth, to estimate the incidence rate. From there, the research pros can determine the required fielding resources, likely timing, and other project design elements in order to build a realistic research approach, budget and schedule. Equally important, they continuously monitor the actual incidence rate as they’re conducting the study so, if need be, they can attempt to mitigate the difference.
So, unless you’re repeating a study for benchmarking purposes, you’re better off not making research budget and schedule assumptions in a vacuum. Instead, turn to a professional research partner — with experience relevant to your specific market and needs — and ask for an estimate and schedule based on an educated incidence rate.