Coding guidelines for inconclusive diagnoses (probable, suspected, rule out, etc.) were developed for inpatient reporting and do not apply to outpatients.
Selection In the outpatient setting, the term “first-listed diagnosis” is used in lieu of principal diagnosis. Diagnoses often are not established at the time of the initial encounter/visit. It may take two or more visits before the diagnosis is confirmed.
Code Range The appropriate code(s) from 001.0 – V83.89 must be used to identify diagnoses, symptoms, conditions, problems, complaints or other reasons for the encounter/visit.
Accurate Reporting For accurate reporting of ICD-9-CM diagnosis codes, the documentation should describe the patient’s condition, using the terminology, which includes specific diagnoses as well as symptoms, problems or reasons for the encounter. There are ICD-9-CM codes to describe all of these.
Code Selection The selection of codes 001.0 – 999.9 will frequently be used to describe the reason for the encounter. These codes are from the section of ICD-9-CM for the classification of diseases and injuries (e.g., infectious & parasitic diseases; neoplasms; symptoms, signs and ill-defined conditions, etc.)
Symptoms, and Signs Codes that describe symptoms and signs, as opposed to diagnoses, are acceptable for reporting purposes when a diagnosis has not been established (confirmed) by the physician.
Circumstances Other Than Disease or Injury The Supplementary Classification of Factors Influencing Health Status and Contact With Health Services (V01.0 –V83.89) is provided to deal with occasions when circumstances other than disease or injury are recorded as diagnoses or problems.
Code Specificity ICD-9-CM is composed of codes with either 3, 4, or 5 digits. Codes with 3 digits are included in the heading of a category of codes that may be further subdivided by the use of fourth or fifth digits, which provide greater specificity. A code is invalid if it has not been coded to the full number of digits required for that code.
Code Sequence List first the ICD-9-CM code for the diagnosis, condition, problem, or other reason for the encounter/visit shown in the medical record to be chiefly responsible for the services provided. List additional codes that describe any coexisting conditions.
Uncertain Diagnosis Do not code diagnoses documented as “probable,” “suspected,” “questionable,” “rule out”, or “working diagnosis.” Rather, code the condition(s) to the highest level of certainty for that encounter/visit, such as symptoms, signs, abnormal test results, or other reason for the visit.
Please Note: This differs from the coding practices used by hospital medical record departments for coding the diagnosis of acute care, short-term hospital inpatients.
Chronic Disease Chronic diseases treated on an ongoing basis may be coded and reported as many times as the patient receives treatment and care for the condition(s).
Coexisting Conditions Code all documented conditions that exist at the time of the encounter/visit and require or affect patient care treatment or management. Do not code conditions that were previously treated and no longer exist. History codes (V10-V19) may be used as secondary codes if the historical condition or family history has an impact on current care or influences treatment.
Diagnostic and Therapeutic Services For patients receiving diagnostic services only during an encounter/visit, sequence first the diagnosis, condition, problem, or other reason for the encounter/visit in the medical record to be chiefly responsible for the outpatient services provided during the encounter/visit. Codes for other diagnoses (e.g., chronic conditions) may be sequenced as additional diagnoses. For outpatient encounters for diagnosis tests that have been interpreted by a physician, and the final report is available at the time of coding, code any confirmed or definitive diagnosis(es) documented in the interpretation. Do not code related signs and symptoms as additional diagnoses.
Note: This differs from the coding practice in the hospital setting regarding abnormal findings on test results. For patients receiving therapeutic services only during an encounter/visit, sequence first the diagnosis, condition, problem or other reason for encounter/visit shown in the medical record to be chiefly responsible for the outpatient services provided during the encounter/visit. Codes for other diagnoses (e.g., chronic conditions) may be sequenced as additional diagnoses.
The only exception to this rule is that when the primary reason for the admission/encounter is chemotherapy, radiation therapy, or rehabilitation, the appropriate V code for the service is listed first, and the diagnosis or problem for which the service is being performed listed second.
Preoperative Evaluations For patients receiving preoperative evaluations only, sequence a code from category V72.8, Other Specified Examinations, to describe the preoperative consultations. Assign a code for the condition to describe the reason for the surgery as an additional diagnosis. Code also any findings related to the preoperative evaluation.
Ambulatory Surgery For ambulatory surgery, code the diagnosis for which the surgery was performed. If the postoperative diagnosis is known to be different from the preoperative diagnosis at the time the diagnosis is confirmed, select the postoperative diagnosis for coding, since it is the most definitive.
Prenatal Visits For routine outpatient prenatal visits when no complications are present, codes V22.0, supervision of normal first pregnancy, and V22.1, supervision of other normal pregnancy, should be used as principal diagnoses. These codes should not be used in conjunction with Chapter 11 codes (Complications of Pregnancy, Childbirth, and the Puerperium (630-677).