Sometimes the strength of opinions predicts outcomes better than the opinions themselves.
Take the case of adoption in America. While the vast majority of Americans support the practice of adoption, just 25% support it strongly enough to consider doing it themselves.
To understand the strength of opinions from your key stakeholders, use surveys that employ the Guttman scale.
The Guttman scale determines how strongly a survey respondent holds an opinion by using a series of “yes-no” questions or “agree-disagree” statements. This format helps determine not only what a respondent believes, but how strongly a respondent believes it. If you can gauge the strength of each respondent’s opinion, you can predict real-life outcomes with greater accuracy.
In the mid-20th century, mathematician and social scientist Louis Guttman developed a method to predict which test questions his students got right based solely on their final scores. Guttman would list test questions from least to the most complex, then count down the list until he reached a particular student’s score. Everything above that point, the student got right. Everything below, the student got wrong. He applied this method to his work in social science.
The Guttman scale is based on a hierarchy of related questions. Respondents must answer “yes” or “no” to dichotomous questions that represent an increasingly extreme position on an issue. The more often a respondent answers “yes,” the more that respondent supports a particular opinion. By listing questions from least to most supportive, you can connect the number of times the respondent answers “yes” to a particular opinion.
The Guttman scale is a commonly used unidimensional scale, like the Likert scale and the Thurstone scale. The Guttman scale is also known as cumulative scaling or scalogram analysis. It is an ordinal scale with a number of statements placed in a hierarchical order. The order is arranged so that if a respondent agrees with a statement, they will also agree with all of the statements that fall below it in extremity. The first statement that indicates disagreement shows the respondent’s position on the subject.
To truly understand how the respondent feels about a topic, statements should be formulated and ordered to represent an increasingly extreme stance on an issue (least to most supportive of the topic). It’s best to engage a group to help create and place statements in order to reduce the risk of bias in both the statements and the order.
Let’s say a respondent is answering 10 Guttman scale questions and answers yes (indicating agreement) on five of them. On the sixth, they stop answering yes. It implies that they agree with the first five and disagree with the remaining five questions.
The value of using a Guttman scale is in the analysis. Use a matrix for scales with fewer statements and scalogram analysis for those with many items.
There are several reasons to use a Guttman scale for your survey:
A Guttman scale survey is a series of related, dichotomous questions or statements. There are many examples of dichotomous questions in SurveyMonkey’s Question Bank. Generally, we advise against using dichotomous questions in surveys unless you’re doing it in a controlled way, like in a Guttman scale. Take this simple question on political views, for example:
Are you a registered voter?
The Guttman scale would combine the question above with related questions that represent an increasingly supportive (or, alternatively, critical) position of voting, such as:
Do you vote in every presidential election?
Should voting in all elections be mandatory?
Another example is using Guttman scale in an educational setting to assess the mathematical abilities of primary students.
The student is able to count to 100.
The student is able to perform addition.
The student is able to perform subtraction.
The student is able to solve multiplication problems.
The student is able to solve division problems.
Each statement indicates a higher level of skill in primary mathematics. A teacher can use this scale quarterly or annually to assess their student's math abilities. If they respond yes to a question, it indicates that they have responded yes to the previous questions.
Consider this Guttman scale example to assess views on mental health:
Depression affects many people in our society.
Depressed people should seek help from their doctors.
Medication can help with depression
Therapy and medication can help with depression
All depressed people can be helped with medication and therapy.
The answers to these questions reveal the respondents’ views and attitudes toward depression.
You can apply the Guttman scale to a wide range of surveys. Here are some examples for when you’d use it:
If customer satisfaction is an area of focus, check out our survey methodologist-approved questionnaire templates. And what about employee engagement? We’ve got plenty of templates covering that topic as well.
Follow these 4 steps to create a survey that utilizes the Guttman scale:
1. Identify a research question that’s related to opinion or sentiment.
As you put your questions into your SurveyMonkey survey, use the “Score this question (enable quiz mode)” feature or add weight to your matrix/rating scale question.
Simply assign each “yes” or “agree” answer a score of 1 and each “no” or “disagree” answer a score of 0. The score of each quiz represents the respondent’s strength of opinion, where a higher score indicates a more supportive opinion.
3. Order the questions from least to most supportive. While you can order the questions yourself, the risk of bias is lower if a study group takes on the task.
You can compare the Guttman scale results across respondents and groups to measure their relative level of support.
Respondents who have higher final scores hold relatively more supportive opinions than others; while groups that have a higher average score hold more supportive opinions than other groups. Once your responses come back, you’ll be able to make these comparisons using SurveyMonkey Analyze.
Guttman scale questions are used to assess attitudes in political science, public opinion, market research, psychology, and anthropology. It’s a fast, concise way to hone in on the strength of your respondents’ attitudes and opinions on a limitless number of subjects. How will you incorporate a Guttman scale into your research?
Ready to start measuring the strength of your respondents’ opinions? Begin by creating a new survey.