Validating the diagnostic code for acne in a tertiary care dermatology centre.

Area of Science:

• Dermatology
• Medical Informatics
• Epidemiology

Background:

• Administrative databases are crucial for population-based health studies.
• Validation of diagnostic codes for dermatological conditions using administrative data is lacking.
• This study addresses the need to validate specific diagnostic codes in dermatology.

Purpose of the Study:

• To assess the accuracy of the International Classification of Diseases, Ninth Revision (ICD-9) code 706 for identifying acne patients.
• To determine the validity of using ICD-9 code 706 in dermatological research.

Main Methods:

• Retrospective chart review of dermatology clinic patients.
• Comparison of billed ICD-9 code (706) with documented medical chart diagnoses.
• Data collected from March 1 to May 31, 2013, at Sunnybrook Health Sciences Centre.

Main Results:

• A total of 4,248 participants were reviewed.
• ICD-9 code 706 was assigned to 201 patients with acne.
• The code demonstrated high positive predictive value (84.58%) and sensitivity (86.29%), with excellent specificity (99.20%).

Conclusions:

• ICD-9 code 706 is a reliable code for identifying patients with acne in a clinical dermatology setting.
• The findings support the use of this code in future epidemiological research on acne.
• This validation enhances the utility of administrative data for dermatological studies.