Amplitude Research® Article

Mail Surveys -- Best Practices

This Article discusses best practices to consider in the administration of mail surveys. There is no single idea which by itself will dramatically improve response rates. Instead, it is a combination of properly planned steps that can result in overall enhancement. By keeping these practices in mind, it will help insure a quality experience for both the survey participants and the sender, as well as potentially improve response rates.

At the outset, it should be kept in mind that most properly administered mail survey projects are fairly complicated. If done correctly, they are far more involved than simple print, mail, tabulate and report. Companies might want to consider the factors mentioned below when planning a mail survey:

  1. Is the length of the questionnaire appropriate for the audience?
  2. Is there a well-written cover letter and instructions?
  3. Is there a method of reaching someone in the event of support issues?
  4. Is the mailing envelope properly identified?
  5. Is the mailing being sent out by 1st class USPS?
  6. Is a business reply envelope being used?
  7. Are awards or other incentives needed?
  8. Would an online survey increase the response rate?


Design of the Questionnaire:

The length of the questionnaire must be appropriate for the audience. A survey participant who pays $50.00 for a product that is readily available from multiple vendors and is not a priority purchase will be far less likely to complete a long questionnaire than a participant who purchases an expensive car or an enterprise product. This is a matter of common sense. Consider how much time you would be willing to spend responding to a questionnaire - given the subject and offered incentives, if any. In many cases, a one-sheet questionnaire printed on both sides (called "duplex" printing) is the appropriate length. This still might be too long depending on the subject of the survey.

Survey length is also determined by the topic. For example, there are only so many questions that can be asked about the taste of toothpaste. Yet some companies might include six or seven basic questions, 10 demographic questions, and another bank of questions on buying habits. Before you know it, the questionnaire is close to four pages long. If this happens, incentives might be needed to reduce the overall project cost (more about this later).

Packaging the Survey Instrument:

There are certain best practices a surveying company should consider relating to the packaging of the questionnaire. This starts with what the participant first sees when he/she receives the mailing. The mailing envelope should include the logo and colors of the sender so that the participant views this as an "official" mailing. The use of color logo might increase the printing costs, but it should be strongly considered unless the cost is too expensive give the project budget.

Use of window envelopes is preferred; although labels can be used if needed. The advantage of a window envelope is the personalization of the cover letter without the need for and cost of a match with the mailing envelope. We recommend the use of a concise, personalized cover letter signed by a person of high authority at the sender. The letter should include the purpose of the survey, confidentially rules, support information, and the end date of the survey. Instructions on completing the questionnaire should be included in the cover letter - - or even better at the beginning of the instrument.

Except for rare instances, the use of 1st class USPS and business reply postage are important practices. Each will add to the cost of the project - and can result in significant cost increases - but they each can have a significant impact on response rates. Use of bulk rate postage can also result in delays in receipt of the mailings for varying percentages of participants.

Use of Incentives:

Deciding whether or not to use incentives is for the most part a budgetary consideration. In certain cases, it can also have a customer-relations aspect. Assuming large quantities of available sample, one can always send out more mailings instead of offering incentives. However, the key consideration is whether the use (and costs of administration) of an incentive saves money by producing more completes at a lower overall cost than sending out additional mailings. If the survey population is limited in size, then awards might be needed to produce an adequate number of completes for actionable data. Keep in mind that there might be quality of data issues relating to the use of incentives.

Coordination of Mail and Online Surveys:

It is not uncommon to use an online survey in conjunction with a mail survey. If this is done, best practices suggest a variable insert of a unique login id onto each paper questionnaire along with survey login instructions. The login id would also function as a tracking id to de-dupe responders who complete both the mail survey and online survey. Technical support should also be available for online responders.

As is the case with incentives, the use of an online survey is primarily a budgetary consideration. That is, will the use of an online survey enhance overall response rates to offset the added costs of offering this option? If not, then the use of an online survey might not be justified unless it is desirable from a client-relations standpoint. Also, keep in mind when calculating the comparative costs that mail surveys have data entry fees while online surveys do not.

In summary, when conducting mail surveys, each and every step of the survey administration process must be carefully considered. That includes length of the questionnaire; packaging of the survey materials including mailing envelope; formatting and personalization of the cover letter; type of postage; participant support options; use of incentives; and viability of a coordinated online survey.

About the Author:

Marc I. Tillman is a member of the professional services staff at Amplitude Research, Inc., a full-service mail and online survey company headquartered in Boca Raton, Florida. Please visit Amplitude's mail surveys page to learn more about its service offerings.

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