How do you test for a medical condition?

From the Guidelines

Testing for a medical condition typically involves a combination of methods tailored to the specific condition being investigated, starting with a thorough medical history and physical examination, as recommended by the British Journal of Sports Medicine in 2020 1. To test for a medical condition, a healthcare provider will usually conduct a thorough medical history and physical examination to identify symptoms and risk factors.

• The physical examination could include neurological screening tests, assessment of mobility and/or muscle strength, as outlined in the British Journal of Sports Medicine in 2020 1.
• Diagnostic tests may then be ordered, which can include blood tests to check for biomarkers, infections, or abnormal cell counts; imaging studies such as X-rays, CT scans, MRIs, or ultrasounds to visualize internal structures; or specialized tests like electrocardiograms for heart conditions or pulmonary function tests for lung disorders.
• For some conditions, tissue samples may be collected through biopsies for microscopic examination, and genetic testing can identify inherited conditions or predispositions.
• The selection of appropriate tests depends on the suspected condition, with healthcare providers following a systematic approach to rule in or rule out possible diagnoses, as suggested by the American Family Physician in 2014 1.
• Test results are interpreted in the context of the patient's overall clinical picture, as no single test is usually definitive on its own, and additional diagnostic tests, such as bone scans, should be carried out if clinically indicated, as recommended by the Annals of Oncology in 2007 1.
• The utility of applying a test may vary between populations and within populations between individuals with different pre-test probabilities of disease, as noted by the European Heart Journal in 2006 1.
• A comprehensive approach, including screening patients to identify those with a higher likelihood of serious pathology/red flag conditions, as recommended by the British Journal of Sports Medicine in 2020 1, helps ensure accurate diagnosis and appropriate treatment planning.

From the Research

Testing for a Medical Condition

To test for a medical condition, several steps can be taken:

• The medical history is the most important factor in making a diagnosis, as it leads to the final diagnosis in most cases 2, 3
• The physical examination can also be useful in making a diagnosis, although it is less important than the medical history 2, 3
• Laboratory investigations can be used to confirm or rule out a diagnosis, and can also be used to monitor the progression of a disease 2, 3
• Diagnostic tests can be used to confirm or rule out a diagnosis, but their results must be interpreted in the context of the patient's medical history and physical examination 4
• The clinical utility of a diagnostic test is also important, as it expresses the extent to which diagnostic testing improves health outcomes relative to the current best alternative 5

Types of Diagnostic Tests

There are different types of diagnostic tests, including:

• Diagnostic tests, which are used to confirm or rule out the presence of a condition in people suspected of having it 4
• Screening tests, which are used to determine who in a large group of people has the condition, often when those people are unaware of it or unwilling to admit to it 4
• Laboratory investigations, which can include blood tests, imaging tests, and other types of tests 2, 3

Interpreting Diagnostic Test Results

When interpreting diagnostic test results, it is important to consider:

• The accuracy of the test, including its sensitivity and specificity 4
• The prevalence of the condition being tested for, as this can affect the accuracy of the test results 4
• The clinical utility of the test, including its ability to improve health outcomes 5