The goal of this stepped-wedge cluster randomized trial is to assess the impact of a laboratory test overuse intervention bundle on laboratory test utilization in 6 health authorities (16 hospitals) in British Columbia. The main question it aims to answer is if the intervention bundle, inclusive of healthcare provider and patient engagement tools, can be effectively implemented for hospitalized medical inpatients in 16 hospitals across BC and reduce laboratory test over-use. Researchers will compare hospital clusters that receive the intervention at different (sequential) time points to see if there are significant changes in the measured outcomes after the intervention.

This study aims to reduce unnecessary laboratory test use in hospitals using a stepped-wedge cluster randomized trial design. Over-use of laboratory testing in hospitals leads to patient discomfort, disruption of sleep patterns, and is associated with hospital-acquired anemia. The specific tests that the investigators focus on are complete blood count, electrolytes, creatinine, urea, international normalized ratio and partial thromboplastin time. After the initial control period, the investigators will begin with a pilot-phase for a feasibility assessment of the intervention tools. The intervention bundle will then be rolled out sequentially, one cluster (each cluster containing 2-3 hospitals) at a time in 12-week implementation steps.

The intervention bundle will contain tools to promote education around appropriate use of laboratory testing in hospitals (using an online module, clinical decision support tool), will share data on laboratory test utilization patterns locally, and include patient engagement materials (infographic and video).

Local champions in hospitals will form multidisciplinary implementation teams to facilitate adaptation and delivery of implementation tools within local context. A pragmatic stepped-wedge design will be used to implement the intervention bundle in 16 hospitals grouped into 8 clusters.

The first 4 weeks of implementation will be a pre-intervention period, trialing and adapting tools to the local context. Readiness assessments and workflow observations will be conducted to understand organizational readiness for implementation. Clusters will enter the intervention period during the latter 8 weeks of the implementation period where intervention tools will be deployed.

Data will be collected for at least 24 weeks post-implementation, evaluating the impact of tools without dedicated personnel support. Access to educational resources will continue, and laboratory utilization reports will be sent.

Participants involved in this study include the following groups: patients and healthcare providers (including learners, physicians and allied health staff)

Inclusion Criteria:

• Patients: The study will include all adult general medical patients that are admitted to the selected hospital during the study period under general internal medicine or family medicine (hospitalist) provider groups.
• Attending Physicians: All physicians who provide patient care in the general internal medicine or family medicine (hospitalist) provider groups in selected hospitals
• Learners and allied health staff (Medical Students/Resident physicians/Clinical Assistants/ Nurse Practitioners, etc.): All those who help take care of patients and can order labs during the study period in the under general internal medicine or family medicine (hospitalist) provider groups in selected hospitals The date range for both groups will extend from May 2024 until study completion in October 2026.

Exclusion Criteria:

• Patients: all patients in specialized medical units (e.g., coronary care, dialysis units, bone marrow transplants units etc.), in critical care, pediatric, obstetrical, surgical, and psychiatric units.
• Patients and Health Care Providers (HCPs) who are not in the internal medicine or family medicine groups