An important component of primary care is that it is continuous, allowing the physician and the patient to develop a relationship over time. This makes it possible for primary-care physicians to accumulate information about personal family history that would not be available to other specialists.
Primary-care physicians try to be community- and population-focused. A doctor can practice high-quality primary care only if he or she knows the community, knows what is prevalent in the community, knows the risks in the community, and knows what the community’s health concerns are.
An important characteristic of primary-care practice is that the physicians see common problems. They specialize in breadth of knowledge and expertise. At the same time, they need to recognize patterns that suggest the unusual. In order to practice in this way, primary-care physicians need information systems and decision support. Because they have a very high volume of practice, their support systems must work on time and all the time. Primary-care physicians cannot wait until the evening or the next day to come up with answers.
In primary care, medical tests and interventions must be appropriate for populations in which rare conditions are actually rare. Tests with even small errors can have magnified effects. A test that has a 99.9 percent specificity can still be a catastrophe in primary care if the condition is rare because positive tests will often be false positives, requiring a further cascade of medical testing and intervention. Rare conditions are rare in primary care, as they are in populations.
For primary-care physicians to incorporate a new test or innovation, several conditions must be met. First, a new test or innovation must be available, feasible, and acceptable to the patient. It has to do what it says it does. It has to be accurate and reproducible. It has to improve clinical outcomes that patients would notice and care about when compared to current practice. For example, changes in laboratory values are usually not enough in primary care because the patient expects to actually experience improvement with a new test or innovation. A new innovation should not increase adverse effects. Finally, it should be “worth it”—that is, the patient should think it is worth it either with insurance or with out-of-pocket payments. The calculation that goes into determining worth is more complex and nuanced than what typically goes into a cost-effectiveness analysis.
Primary-care clinicians need authoritative advice. No one can keep up with the staggering volume of medical information or make sense of all the volumes of literature. Authoritative advice can help clinicians deal with complex decisions by identifying the key factors important to decision making. Furthermore, authoritative advice has the potential to improve the quality of physician decision making. Such advice can provide justification to patients, payers, and the legal system by presenting the criteria used to make decisions.