Which criterion is commonly cited as a limitation in ultrasound research?

• A. Research is flawed
• B. Not enough subjects used
• C. Only heat small area
• D. All of the above

Answer: (D)

Ultrasound research is often limited by multiple real-world factors, so the best answer recognizes that all of the commonly cited issues can appear together. Methodological flaws in study design—things like inadequate controls, potential biases, or inconsistent procedures—can skew results about what ultrasound actually does. Not having enough subjects reduces statistical power and makes it harder to generalize findings to larger populations. And because ultrasound energy tends to heat only a small, localized area, effects outside that zone may be missed or not representative of broader tissue responses, complicating dose interpretation and extrapolation. When you put these together, it’s clear why “all of the above” is cited as a common limitation in ultrasound research.