Laboratory testing

Hospital-wide, Internal medicine

Laboratory testing

Hospital-wide, Internal medicine
Inappropriate use of laboratory diagnostics is a well-known phenomenon in clinical practice. About 20% of the laboratory tests that we use in routine daily practice are unnecessary.

Inappropriate use of laboratory diagnostics is driven by multiple factors, for example defensive behavior and fear of uncertainty, the strict use of protocols and guidelines and lack of feedback and knowledge about the costs and consequences of laboratory testing. A pilot study aiming to reduce unnecessary testing through a multistep intervention at the Internal Medicine department of the Amsterdam UMC location VU showed a 13% reduction in diagnostic expenses.

This project aims to reduce unnecessary use of routine clinical chemical laboratory tests in the hospital.


This project was a before-after study, conducted in the Internal Medicine departments of four large training hospitals in the Netherlands. The intervention consisted of creating awareness through education and feedback, intensifying the supervision of young doctors with regard to laboratory testing by experienced specialists and changes in protocols and (electronic) ordering systems. The primary outcome measure was change in the number of laboratory tests per patient contact, secondary outcome measures were a change in the costs of laboratory tests, and numbers and costs of orders for radiology, microbiology and nuclear medicine per patient contact. The effect of the intervention was analyzed using an “autoregressive integrated moving average” (ARIMA) model with correction for seasonal effects. In addition, clinical outcomes and barriers and facilitators for de-implementation have also been studied.


The average number of tests per contact moment in the four participating hospitals fell by an average of 11%. The reductions in the four hospitals separately over the last 6 months of the project compared to the same 6 months a year earlier were 11.5%, 5.9%, 8.3% and 14.7%. There was a 2% increase in the control group of 19 hospitals.

The costs of laboratory tests and the numbers and costs of orders for other diagnostics also decreased. No clear negative effect on clinical outcomes were measured.

Important facilitating factors were education and scientific evidence, feedback of ordering behavior, reminders, role models in an enthusiastic project team and involvement of physician assistants. Important barriers were lack of time, high turnover of physician assistants and availability of data.


At the moment, this project is being completed. In the following years, this de-implementation strategy will be scaled up to other hospitals in the Netherlands.

Learn more:

Contact us at


Prof. Prabath Nanayakkara, PhD, MD

| Amsterdam UMC

Renuka Bindraban, MD

| Amsterdam UMC

Marlou van Beneden

| Amsterdam UMC