Six Sigma and Beyond: Statistics and Probability, Volume III

Here are a few hints about things you can do when designing your form that will make your life a lot easier when it comes time to analyze the data. Some of these hints pertain to the arrangement of the form, and some are about coding.

To design a form well, you should:

• Split up complicated questions. Some questions are best asked in parts .

• Record numbers when you can. Record information in as much detail as possible, using actual numbers. Later, you can use the computer to create categories such as small, medium, and large based on the exact numbers. If you have recorded only the categories, you will not be able to try different grouping schemes or to analyze the data in more detail. (Exceptions to this rule exist. For example, if you are a marketer, you may need to ask people about their incomes. The questions that you ask should not focus on the precise income. That is because income is a sensitive matter for many people, and they may refuse to give their income as an exact number of dollars; or they may not know their yearly income to the nearest dollar. If you are sensitive to these types of questions ahead of time you can soften the question by letting the interviewer hand a card to the respondent with preprinted income categories. That way, the respondent never needs to give an exact figure. Analyzing income categories may be harder than analyzing exact incomes ” but the situation would be even worse if people refused to answer at all or if they gave false answers.)

• Use a numeric coding scheme. When items require coding, assign numbers instead of letters to the responses. Numbers simplify both data entry and data analysis. For example, coding "comfortable ride" as 1 and "uncomfortable ride" as 2 is simpler than the actual adjective used in the study.

• Put an identification number on the form. You can use the identification number to locate forms that you later find to have errors or unusual values. Even if you are running a confidential survey, and each form is not linked to a particular person, put an identification number on the respondent's form before you enter the data into the computer. Then enter the identification number with the rest of the data. This number links the paper form and the computer record.

• Make sure the data can be entered into a computer directly from the form. This saves time and helps to minimize errors.