The Difference Between Clinical Diagnosis and Legal Causation

By Dr. Steven B. Ross, DC, FASBE, DAAPM

Chiropractic Physician | Fellow, American Academy of Applied Spinal Biomechanical Engineering | Diplomate, American Academy of Pain Management.

A medical diagnosis can explain what is wrong with a patient. It does not, by itself, establish what caused the condition.

This distinction is especially important in personal injury and medical-legal cases, where attorneys may need to determine whether the available evidence supports a connection between an incident and a claimed injury.

Clinical Diagnosis and Legal Causation Are Not the Same

A clinical diagnosis is primarily concerned with identifying a patient's condition based on symptoms, examination findings, medical history, imaging, and other diagnostic information.

Legal causation asks a different question:

Does the available evidence support the conclusion that the event in question caused or contributed to the claimed injury?

The two questions can overlap, but they are not interchangeable.

A patient may have a confirmed diagnosis, yet additional analysis may be necessary to determine whether that condition resulted from the incident being evaluated.

Why Clinical Findings Matter

Clinical findings provide an important foundation for medical-legal analysis.

Depending on the case, an expert may consider:

• The patient's reported symptoms

• Physical examination findings

• Diagnostic imaging

• Prior medical history

• Treatment records

• The timing and progression of symptoms

• The reported mechanism of injury

These factors help establish the medical picture surrounding the claimed injury.

However, the presence of an injury does not automatically establish its cause.

Why the Mechanism of Injury Matters

Understanding how an incident occurred can be an important part of evaluating causation.

For example, in a case involving a spinal injury, an expert may need to consider the forces involved, the direction of impact, occupant position, the mechanics of the incident, and the specific structures affected.

This is where biomechanical analysis can provide additional perspective.

The question is not simply whether an injury exists. The question is whether the proposed mechanism is consistent with the injury and the available evidence.

Pre-Existing Conditions and Alternative Explanations

Another important consideration is the patient's medical history.

A claimed injury may need to be evaluated in the context of conditions that existed before the incident.

This does not mean that a pre-existing condition automatically rules out an injury claim.

Instead, it means the expert should consider whether the available evidence supports the proposed relationship between the incident and the condition.

Alternative explanations may also need to be considered before reaching a causation opinion.

What Attorneys Should Take From This

A diagnosis and a causation opinion serve different purposes.

A diagnosis can establish that a medical condition exists.

A causation analysis examines whether the evidence supports a relationship between that condition and the event being evaluated.

Understanding this distinction can help attorneys ask better questions when reviewing medical evidence and evaluating expert opinions.

The goal of a sound medical-legal analysis is not to assume causation.

It is to examine the available evidence carefully and determine what the evidence actually supports.

Conclusion

The difference between clinical diagnosis and legal causation is an important distinction in medical-legal cases.

A confirmed diagnosis is an important part of the evidence, but determining causation may require consideration of the medical history, clinical findings, injury timeline, incident mechanics, alternative explanations, and other relevant evidence.

For attorneys evaluating a complex injury case, understanding this distinction can help create a clearer framework for evaluating medical opinions and the evidence supporting them.

When medical evidence and legal questions intersect, careful analysis can help ensure that conclusions are based on evidence rather than assumptions.

About the Author

Dr. Steven B. Ross, DC, FASBE, DAAPM is a chiropractic physician, spinal biomechanical injury analyst, Independent Medical Examiner, and expert witness with more than 40 years of clinical experience. His practice focuses on injury causation analysis, spinal biomechanics, chiropractic and medical malpractice, independent medical examinations, and evidence-based medical-legal consulting.