Healthcare decision making ability is measured using a 6-item version of the Decision Making Competence Assessment Tool, created by Finucane. Participants view a module involving tables that provide information about health maintenance organization (HMO) plans (the most common type of managed-care plan for health insurance in the USA). The information provided in the module is designed to simulate materials used in healthcare settings in the real world.

Participants are then asked 6 questions of varying difficulty levels (3 simple and 3 complex) that assess comprehension and integration of the information in the tables. The complex problems parallel the simple problems but present information about many more options. The score for healthcare decision making ranges from 0 to 6 and represents the number of questions answered correctly. If 3 or more questions are missing, then the score cannot be calculated.

Participants are asked the following questions based on the tables they are provided:

1. Look at the information provided and tell me, what percentage of members are very satisfied with physician access?
2. Now, in one year, what will this HMO's monthly premium be?
3. Suppose you don't want any HMO that is below average on member satisfaction OR below average on access to specialists. Based on the information in this table, which HMO should you choose?
4. What is the lowest copayment for a visit with a primary care doctor?
5. And which HMO provides the best overall treatment quality according to members' ratings?
6. Based on the information in this table, which HMO should you choose?

Note: In previous research, the decision making measure has been shown to have adequate psychometric properties including high inter-rater reliability and short-term temporal stability.