Measuring the involvement of people with HIV in treatment decision making using the control preferences scale

Since 1983, HIV patients have been advocating for participatory decision making. This study measures the involvement that HIV-positive people perceive in treatment decision making. A secondary objective is to assess the validity of the instrument used to examine decisional roles, the Control Preferences Scale (CPS).

The authors interviewed 79 HIV-positive people, a sub-sample of a study on long survival with HIV, diverse with respect to ethnicity, age, gender, and sexual orientation. They compared the self- and researcher-rated decisional roles of participants on the CPS. They also assessed how well the CPS corresponds with Charles's paternalistic, shared- and informed-choice models of decision making about treatment based on decisional roles and information exchange.

Most participants (75%) perceived collaborative/active involvement in decision making. Agreement (Kendall's tau-b) between self- and researcher-rated decisional roles on the CPS was 0.82, whereas agreement between self-ratings on the CPS and researcher ratings on Charles's classification was 0.60. Charles's classification was difficult if participants had chosen not to take their prescribed medication without being adequately informed about the risky consequences of this decision.

In this study, HIV-positive people perceived a high level of involvement in decision making. Reliability and convergent validity of the CPS was high. Charles's classification was problematic because decisional roles and information exchange are distinct dimensions. Some people make risky treatment decisions on their own without being adequately informed. The CPS is a useful instrument to measure decisional role perceptions of HIV-positive people but needs to be complemented by an instrument measuring treatment knowledge.