After a new pharmacy dispensing system is implemented, issues are reported regarding pharmacies not being...

Acceptance testing (User Acceptance Testing/UAT) is the testing phase most likely to identify an inability to process prescriptions that existed before cutover , because UAT validates that the solution supports real operational workflows and business requirements under conditions that mirror production use. A key go-live risk in pharmacy system replacement is data conversion and continuity of care : prescriptions entered in the legacy system prior to cutover must be accessible and actionable in the new environment (e.g., visible in work queues, eligible for verification, dispensing, labeling, adjudication, and documentation). In well-designed acceptance testing, users execute scripted scenarios that include “pre-cutover” items—converted orders, historical prescriptions, and in-flight work—specifically to confirm that the new system can safely continue processing without interruption.

By comparison, unit testing focuses on individual components and would not validate end-to-end prescription processing across converted legacy data. System integration testing emphasizes interfaces between systems (e.g., EHR-to-pharmacy, claims, automation) but may not adequately validate business readiness with converted pre-cutover prescriptions unless explicitly included. Regression testing checks that changes did not break previously working functions, but it is not the primary phase for validating cutover continuity. Therefore, acceptance testing is the best answer.