| Strengths |
• Adequately powered |
| • Internal validity due to unbiased methodology, for example, narrowly defined study population, randomization, blinding, and inclusion of control groups |
| • Scientifically robust |
| • Provide substantial information regarding the efficacy and safety of interventional products |
| • Prospective design |
| • Prespecified, well-defined end points |
| Weaknesses |
• Lack external validity and generalizability to different settings |
| • Lack statistical power if sample size is not large enough to answer research question |
| • Can be hampered by ethical and practical considerations |
| • Do not provide all evidence required for medical decision making or guide patient-centered care |
| • Require a lot of investment in terms of finances, resources, and time |
| • Restrictive enrollment criteria; involve homogeneous patient populations, which are not reflective of those seen in real-life clinical settings |
| • Often conducted over a shorter period of time than is required to fully assess the clinical and economic impact of a medical intervention |
| • Volunteer bias |
| • “Placebo” response |
