Diagnostic tests for children — are we getting it right?

Diagnosing medical conditions in children can sometimes be difficult for general practitioners (GPs). Unlike adults who might be able to describe their symptoms, for young children especially, doctors must rely on a child’s appearance, physical examination as well as measurable tests, such as blood tests or X-rays, to help make a diagnosis.

It can be hard to know what the “right” level of testing is. If a four-year-old has a fever and complains of tummy pain and pain while urinating and the GP doesn’t request any tests, they could miss an infection with potentially serious consequences. On the other hand, if a child receives a test they do not need, they may experience unnecessary pain and/or anxiety. A test might show an abnormal result by chance but lead to a cascade of further unnecessary testing and treatments that cause more harm than benefit.

Doctors refer to clinical guidelines which provide a rough guide of which tests to use and when. Testing that falls outside these recommendations may be considered inappropriate

Looking at differences in healthcare (or in our case testing) over time or geographically can also potentially tell us about what might be the right level of care. In 1938, JA Glover became a pioneer of this concept when he described an epidemic of “enlarged tonsils” in England. He found that in certain areas school children were having 4 times more tonsillectomies than other areas, irrespective of illness rates, economic factors and access to care. This research showed that many tonsillectomies were likely to be unnecessary and mostly performed based on doctors’ and patients’ preferences. With large datasets of electronic medical records, it is possible to carry out similar research looking at test use across England to identify areas of testing variation and highlight possible cases of inappropriate testing.

Once we identify areas of variation it is just as important that we seek to understand why these differences exist. Is there truly more disease in some areas? Could variation be related to a person’s wealth, education or ethnicity? What factors influence a GP’s decision to request (or not request) a test for a child?

Our study

Our research team is conducting a project to address these key questions. It consists of two parts:

Part One

We will use data from a large primary care database called the Clinical Practice Research Datalink. The database contains anonymous data for 60 million patients in the UK. We will use this to see how testing in children has changed over time and how different it is between practices. Possible reasons for these differences will be explored, like the family’s level of social and financial status, whether they have other medical conditions, and how many children have the disease related to the test.

Part Two

We will interview with GPs in the Thames Valley and South Midlands to understand their test-ordering practices for children, ask them why they think there are differences in testing and what factors they consider when deciding to request (or not request) a test for a child.

This project is funded by a grant from the National Institute for Health and Care Research School for Primary Care Research (Grant Ref No: 624).

We welcome any comments or feedback on our work, so please get in touch or post a comment below. We are recruiting parents and public contributors to advise us on several aspects of this project, including the types of tests to prioritize for study, the types of questions we ask GPs to explore the factors associated with testing in children, and how to share our findings with the public. We aim to include a diverse range of contributors, so if you are interested in getting involved please fill out this survey.

 ___________________________________________________________________________________________

Elizabeth Thomas is a medical doctor and DPhil candidate at the Centre for Evidence-Based Medicine at the University of Oxford, funded by a Clarendon Scholarship. You can get in touch with her on Twitter @_ETThomas or via email: elizabeth.thomas@phc.ox.ac.uk.