How Much of Modern Medicine Is Truly Based on Science?

From time to time I run into people who tell me alternative treatments are not scientific, but is modern medicine scientific? Most people assume that modern medicine is firmly rooted in rigorous scientific evidence. However, the reality is more complex. While many medical treatments are backed by extensive research, a surprising percentage of commonly used interventions lack strong scientific support.

A frequently cited estimate from Dr. David Eddy, a pioneer in evidence-based medicine, suggests that only about 10-20% of medical treatments are backed by solid, high-quality evidence from randomized controlled trials (RCTs). Other analyses, such as those from the British Medical Journal’s Clinical Evidence database, indicate that only about 11% of medical treatments have strong evidence supporting their effectiveness, while another 50% fall into the category of having “unknown effectiveness.”

Why Is the Percentage So Low?

Several factors contribute to the lack of strong scientific backing for many medical treatments:

1. Lack of Large-Scale Studies – Many treatments have not undergone large, double-blind RCTs, which are considered the gold standard of medical research. This can be due to ethical concerns, financial constraints, or the difficulty of designing such studies.

2. Historical Practices Persist – Some treatments continue simply because they have always been used, even when scientific evidence is weak or outdated. For example, routine surgeries like spinal fusion for back pain or arthroscopic knee surgery for osteoarthritis have been called into question by recent studies, yet they remain common.

3. Pharmaceutical Industry Influence – The medical field is heavily influenced by pharmaceutical companies, which fund a significant portion of clinical research. This often results in biased studies that favor new drugs over non-pharmaceutical treatments or older, generic options.

4. Placebo Effect and Practitioner Belief – Some treatments persist because they seem to work anecdotally, even if rigorous scientific validation is lacking. The placebo effect and physician enthusiasm can make a treatment appear more effective than it actually is.

The Importance of Evidence-Based Medicine

While the medical field has made significant strides in applying scientific rigor, much work remains. Patients and healthcare providers should critically evaluate treatments, seeking those backed by strong, independent research rather than tradition, financial incentives, or weak evidence.

Ultimately, a significant percentage of medicine operates in a gray area of uncertainty. This makes it essential for patients to stay informed, ask questions, and consider alternative approaches—especially those that focus on root causes rather than just symptom management.