Which of the following is not part of the secondary assessment for illness?

In the context of a secondary assessment for illness, the primary focus is on gathering detailed information about the patient's condition. This typically includes evaluating symptoms, establishing any allergies that could affect treatment, and determining the last intake, which can inform medical decisions and interventions.

Blood pressure, while a key vital sign in assessing overall health and certain medical conditions, is not a standard component of the secondary assessment specifically for illness. The secondary assessment is more about understanding the illness’s specific characteristics rather than the broader vital signs that are tracked in various assessments. Hence, blood pressure does not directly correlate with assessing an illness, making it the correct choice in this scenario.