Medical decision making (MDM) refers to the process clinicians use to make decisions and draw conclusions from any available medical data. There are many steps involved in a complete MDM process.

  1. The clinician interprets available patient data, including symptoms, test results, patient self-reporting, his or her own observations and anything else professionally relevant.
  2. The clinician may obtain or refer to previous medical records for relevant patient history or diagnoses, previous testing, or may compare current test results to previous results.
  3. The clinician considers a differential diagnosis, acknowledging all possible diagnoses which could explain the given medical data.
  4. The clinician eliminates certain differential diagnosis possibilities, settling on a diagnosis or concluding further investigation is needed to rule out multiple possibilities.
  5. Instructions for each diagnosis or possible diagnosis in order to provide the best possible care given the patient’s condition and relevant medical history.
  6. The clinician may discuss a case with a patient’s primary care physician or consultants.

The MDM process uses a number of skills clinicians acquire through every day practice and training in order to make an informed decision to produce the optimal outcome for a patient.

Medical billing often uses MDM to justify the use of certain coding levels. More complex situations, such as unknown conditions vs. known conditions or high-risk conditions vs. low-risk conditions, correlate with higher coding levels. To aid in this coding practice, an MDM complexity score may be applied using a rubric.