HONcode Certified

This website is certified by Health On the Net Foundation. Click to verify.

This site complies with the HONcode standard for trustworthy health information: verify here.

Understanding clinical risk scores in 4 days. Day 1: Diagnosis

Ami Banerjee
Last edited 20th April 2011

Risk is arguably one of the most central concepts in clinical medicine. Patients want to know their risk of a particular disease or perhaps even death. Clinicians are interested in which patients are at highest risk of disease and complications. Researchers want to establish the way in which new treatments change the risk of disease. Clinical risk scores use available information to predict the risk of a particular clinical scenario. Risk scores cannot replace clinical judgment but they can guide it. There are hundreds of risk scores available to clinicians and many are available online as risk calculators and are widely used by patients. In this 4-day series, I will cover the 4 types of clinical risk score.


Some diseases are easy to diagnose because they are well-defined. For example, infection with HIV is diagnosed by a positive HIV test. However, not all diseases are so easy to diagnose or have such clearly defined criteria. Lack of diagnostic certainty can lead to inappropriate treatment and can even lead to abuse of the social benefits system by some unscrupulous parents in the case of attention deficit hyperactivity disorder(ADHD)

Diagnostic scores can be helpful in identifying disease, but also in describing severity of disease. In depression, the Beck’s depression inventory (BDI) is a score which describes the severity of depression on a continuous scale, with 0–9 indicating minimal depression, 10–18: mild depression, 19–29: moderate depression and 30–63 indicating severe depression. A score of at least 10 on the Beck Depression Inventory is the generally accepted threshold for the indication of possible depression.

The mini-mental test score (MMTS) is the most commonly used diagnostic test to assess cognitive function. Scores of 25-30 out of 30 are considered normal. NICE classify 21-24 as mild, 10-20 as moderate and <10 as severe impairment.

Diagnostic scores must be tested and validated in well-defined populations because the scores may perform differently in different patient groups. For example, the BDI above is good at diagnosing depression in post-stroke patients.

The term “clinical prediction rules” is often used to describe the use of clinical findings (history, physical examination, and test results) to make a diagnosis, OR to predict an outcome. This article from Annals in Internal Medicine sums up what you need to know about diagnostic scores before you use them on your patients.

Twitter TrustTheEvidence.net


Search the TRIP Database

TRIP Database


Recent Comments