Background: Administrative claims are readily available, but their usefulness for identifying persons with non-small cell lung cancer (NSCLC) is relatively unknown, particularly for younger persons and those enrolled in Medicaid.
Objectives: To determine the sensitivity of ICD-9-CM codes for identifying persons with NSCLC.
Methods: This was a retrospective analysis of insurance claims records linked to the Surveillance, Epidemiology, and End Results (SEER) cancer registry for the time period January 1, 2002, through December 31, 2005. Persons included in the sample were identified with NSCLC using SEER morphology and histology codes and were enrolled in a commercial health plan, Medicaid, or Medicare fee-for-service health plans in Washington State. The outcome measure was sensitivity, defined as the percentage of SEER-identified patients who were accurately identified as NSCLC cases using ICD-9-CM diagnoses (162.2, 162.3, 162.4, 162.5, 162.8, 162.9, or 231.2) recorded in any claim field in administrative claims data. We examined the influence of varying the number and timing of administrative codes in relation to the SEER cancer diagnosis date. In multivariate models, we examined the influence of age, sex, and comorbidity on sensitivity.
Results: The sensitivity of 1 medical claim including at least 1 ICD-9-CM code for identifying NSCLC within 60 days of diagnosis as documented in the SEER registry was 51.1% for Medicaid, 87.7% for Medicare, and 99.4% for commercial plan members. Sensitivity can improve at the expense of identifying a portion of patients who are 3 or more months from their true diagnosis date. In multivariate models, age, race, and noncancer comorbidity but not gender significantly influenced sensitivity.
Conclusions: Administrative claims are sensitive for identifying patients with new NSCLC in the commercial and Medicare plans. For Medicaid patients, linkage with cancer registry records is needed to conduct studies using administrative claims.