Secondary Interpretation of CT Examinations: Frequency and Payment in the Medicare Fee-for-Service Population

Purpose: Secondary interpretation of diagnostic imaging examinations (providing a second formal interpretation for imaging performed at another institution) may reduce repeat imaging after transfer of care. Recently, CMS requested information to guide payment policy. We aimed to study historic trends in submitted claims and payments for secondary interpretation services in the Medicare fee-for-service population.

Methods: Applying current procedural terminology codes by body part to Medicare Part B aggregate claims files, we identified all CT interpretation services rendered between 1999 and 2012. Secondary interpretation services were identified using combined code modifiers 26 and 77, in accordance with CMS billing guidelines. The frequencies of billed and denied services were extracted for primary and secondary CT interpretation services. Primary versus secondary interpretation denial rates were calculated and compared.

Results: Of all 227 million Medicare Part B claims for CT services, 299,468 (0.13%) were for secondary interpretation services. From 1999 to 2012, growth in secondary interpretation claims outpaced that in primary interpretation claims (+811% versus +56%; compound annual growth rate 17% versus 3.2%). As a percentage of all services, secondary interpretations increased from 0.05% in 1999 to 0.30% in 2012. Denial rates for second interpretations decreased from 1999 to 2012 (12.7% to 7.0%), and now approach those for primary interpretations (5.4% in 2012).

Conclusions: Medicare claims for secondary interpretation of CT examinations are growing but account for less than 1% of all billed CT interpretation services. Denial rates are similar to those of primary interpretation services.