Imagine a primary care visit where no one takes your blood pressure. Instead, your provider looks you up and down and makes a mental note of her impression of what your blood pressure might be. Or she privately concludes in your chart that your blood pressure is likely fine because you don’t mention it as an issue during your interaction. Silly, right? And unlikely, since basing care on reliable assessments — a.k.a. “measurement-based care” — is widespread in most health care.