# When doctors say there’s "no evidence of effect" for medical cannabis, what do they mean?

When physicians claim there is "no evidence of effect" for medical cannabis, they aren’t suggesting the treatment doesn’t work. Instead, they’re referring to a lack of the specific type of research that medical professionals traditionally rely on most heavily. Medical science evaluates treatments through different research approaches, with two primary categories standing out:

1. **Randomized Controlled Trials (RCTs)**
   These are considered the gold standard in medical research. In an RCT, participants are randomly assigned to one of two groups: one receives the treatment being tested, while the other gets a placebo (an inactive substance). Neither the patients nor the researchers know who is receiving which—this "blinding" helps eliminate bias and ensures the results are as objective as possible.
2. **Real-World Evidence (RWE) – Practical, Everyday Studies**
   Unlike RCTs, these studies examine how a treatment performs in actual clinical practice over time. They track outcomes in large groups of patients using the medication in their daily lives. Examples include long-term observational studies following thousands of patients over years or comparative analyses between those who use the treatment and those who don’t.

### Why Are There So Few RCTs on Medical Cannabis?

Several challenges make it difficult to conduct RCTs for medical cannabis:

- **High Costs and Logistical Hurdles**
  RCTs require large participant groups, extended follow-up periods, and tightly controlled conditions—all of which are expensive. Since medical cannabis is difficult to patent, pharmaceutical companies have little financial incentive to fund these studies, leaving a significant research gap.
- **Small Studies Yield Unreliable Results**
  Even when RCTs are conducted, limited funding often restricts them to small sample sizes. A study with too few participants may fail to detect a true effect, even if most patients benefit. For instance, if 80% of a small group experience improvement, the study might still conclude "no effect" due to statistical limitations. This is a major issue for cannabis research, where large-scale trials are rare.
- **Single-Strain Testing Doesn’t Reflect Real-World Use**
  Medical cannabis isn’t a one-size-fits-all medication—it encompasses a wide range of strains and formulations. RCTs typically test just one variant, but in practice, treatment must be tailored to the individual. For example, the UK has approved over 200 different medical cannabis products, each with unique properties.
- **Study Participants Aren’t Always Representative**
  RCTs often enroll patients with single, well-defined conditions and few comorbidities. However, many real-world patients have complex, overlapping health issues. This discrepancy means RCT results may not accurately predict how cannabis will work for the average person.

### What About Other Types of Evidence?

Given the challenges of conducting RCTs, researchers often rely on alternative study designs, such as Real-World Evidence. These studies can demonstrate clear benefits and, according to regulatory standards, should be considered valid documentation. Yet, they are frequently overlooked or dismissed by medical authorities.

Examples of Real-World Evidence include:
- **Longitudinal studies** tracking thousands of patients over years.
- **Case-control studies** comparing outcomes between those who use cannabis and those who don’t.

While these studies can show meaningful results, they are often deprioritized simply because they aren’t RCTs.

So when doctors say there’s "no evidence of effect" for medical cannabis, they’re not claiming the treatment is ineffective. They’re pointing to a shortage of the *preferred* type of research. Many patients—such as those with arthritis—report significant relief from medical cannabis, and studies support these experiences. However, because not all medical communities acknowledge this evidence, cannabis is often rejected as a treatment option, even when it works for patients. The phrase "no evidence of effect" becomes a default response, despite real-world success.

To ensure more patients can access medical cannabis when other treatments fail, we’re actively working to improve education, expand research, and foster transparency around what "evidence of effect" truly means. Through pilot programs and registry-based studies, we aim to gather practical insights into how medical cannabis performs across a broad spectrum of conditions. This knowledge is critical for giving patients and doctors confidence in their treatment decisions.

But change doesn’t happen in isolation. Your voice and involvement matter. As more people understand the challenges and opportunities surrounding medical cannabis, progress becomes possible. You can help by sharing information—with friends, family, colleagues, or anyone who might benefit. Feel free to use our brochures as conversation starters to spread awareness.
