Improving ICD Coding in the Emergency Department: Factors Related to Use of "Unspecified" Codes for Head and Brain Injury

Context: International Classification of Diseases (ICD) codes are used for billing but also for surveillance for injuries such as traumatic brain injuries (TBI). While specificity is possible in the ICD-10-CM scheme, use of the code for unspecified injury of head (SO9.9) remains high.

Objectives: This process evaluation sought to understand medical ICD-10-CM coding behaviors for TBI in emergency department (ED) settings.

Design: Semi-structured interviews explored the processes that facilitate or hinder ED physicians from selecting specific ICD codes for TBI and potential points of intervention for increased coding specificity and reducing the use of unspecified codes.

Setting: Video interviews were conducted with a nationwide sample in the United States.

Participants: A purposive snowball sampling strategy was used to recruit 26 ED physicians with experience diagnosing TBI.

Intervention: Semi-structured interviews identified factors related to the selection of specific ICD codes for head injury.

Main outcome measure: Thematic analysis of transcribed data.

Results: Four main themes emerged from the data: the impact of training and expertise, factors related to diagnosis, unclear connections with medical coders, and actionable recommendations. Interviews underscored the context surrounding "unspecified" codes for TBI, including demands from patient care, time pressures, issues around how a diagnosis may impact patient management decisions, and considerations related to mapping within the electronic medical record (EMR) where options may default to an unspecified code.

Conclusions: Findings from this analysis indicate that ED providers may benefit from more robust training on how documentation can better support ICD-10-CM coding for this type of trauma. Revised EMR structures could support efficient coding specificity and clarity.