Medical testing

DECIDE work with medical testing

The development of evidence-based recommendations of diagnostic tests is less well understood compared to recommendations for therapeutic interventions so we spent some time fine-tuning and elaborating the methods for arriving at diagnostic recommendations, to achieve effective presentation strategies. The central and recurrent theme of the DECIDE approach with regard to medical tests is the need to widen the focus of test evaluations, from relying on diagnostic test accuracy only to using the effect on patient important outcomes as the decisive factor. We have produced two systematic reviews, one on the grading systems used for medical tests and how they use evidence in guideline development, the second looked at the methods used by organisations developing recommendations about diagnostic tests. These led to qualitative work with guideline developers, methodological experts and others that found that diagnostic test accuracy  based on comparisons between test results and the gold or reference standard  was the factor most commonly considered by organisations when formulating recommendations. The majority of experts pointed out that accuracy alone is not sufficient and that recommendations based on accuracy (and not on patient important outcomes) only may be misleading.

Finally, both for guideline users and developers, we have developed frameworks to develop recommendations.

Want more information?  A longer summary of our work on medical testing can be read as a pdf.

Publications

1. Guidelines for guideline developers: a systematic review of grading systems for medical tests (http://implementationscience.biomedcentral.com/articles/10.1186/1748-5908-8-78).

2. Are we missing the point in medical test guideline development: a qualitative study (Submitted).

3. Applying Grading of Recommendations Assessment, Development and Evaluation (GRADE) to diagnostic tests was challenging but doable (http://www.ncbi.nlm.nih.gov/pubmed/?term=Gopalakrishna+G%2C+Mustafa+RA%2C +Davenport+C%2C).

4.  GRADE Evidence to Decision (EtD) frameworks: A systematic and transparent approach to making well-informed healthcare choices: 1. Introduction. BMJ 2016 Jun 28;353:i2016

5. GRADE Evidence to Decision (EtD) frameworks: 2. Clinical practice guidelines. BMJ 2016 Jun 30;353:i2089

6. GRADE Guidelines: 16. GRADE evidence to decision frameworks for tests in clinical practice and public health. J Clin Epidemiol. 2016 Aug;76:89-98

Outputs
1. An Evidence to Decision framework to develop medical testing recommendations - click here for an example.

What is happening now?
We, in the context of the GRADE Working Group activities, are going to continue refining the work produced in the DECIDE project. For example, by implementing the diagnostic Evidence to Decision framework in guideline panels internationally we will further refine the framework and we are exploring how the clinical pathway approach can be integrated in the framework.