To provide good care for people with HIV/AIDS, clinicians need access to timely, clinically relevant information about each patient in the practice, as well as the population of patients as a whole. Useful information includes the following:

• Recommended services (e.g., Pap smear, PPD, rectal examination, immunizations)
• Key outcome measures (e.g., CD4 count, viral load testing, quality-of-life updates)
• Patient contact information
• Patient encounter history (e.g., how often patient accesses care, last time seen)
• Case management updates

A system that records all relevant patient care information is often referred to as a "registry." Providers can use the registry to record critical elements of the care plan, produce quick care summaries at the time of a visit, and enter data to alter the care plan as needed. A patient registry is most useful when patient data are available to the provider at the point of the patient visit, when decision support is most needed.

The registry can remind providers of needed services, represent feedback on clinic and provider performance, and serve as a source of up-to-date information for encounters. Health care teams can also use the registry to contact groups of patients with similar care needs and deliver planned care and educational sessions. Although the registry is an important component of the clinical information system, other elements, such as scheduling and email systems, also support the delivery of good care to patients with chronic conditions such as HIV/AIDS disease.