When evaluating these methods, ask yourself how important each one of the characteristics is to your project. If you need a high response rate and feel that a mailed survey is the right approach, you will have to be diligent in your follow-up contacts. Adding an incentive to return a mailed survey is often helpful, as are follow-up phone calls, cards or other reminders. As I mentioned above, the choice of an administration method has a direct impact on the format of your questions. Questions asked over the phone should be short and easy to read.
Questions written for a mailed survey can be slightly longer and more complex.
They can also refer to other parts of the questionnaire or to additional materials included with it. SPSS Inc. All rights reserved.