GH and family are traveling the stunning California coast between SF and LA.

Traveling South from Big Sur along Hwy 1

Among the sights seen: otters in Monterey Bay, the steep shores of Big Sur (in rock slide inducing rain), and elephant seals near San Simeon. Yet to come are the Hearst castle, Morro Bay, and Santa Barbara.

It’s somehow reassuring to know how sparse the population gets between the Bay Area and Southern California, as if humans won’t eventually overpopulate the planet.

A couple of medical items to share:

Another study on prostate cancer. This one, reported on NPR, questions the validity of the “PSA velocity” concept. PSA is a blood test men can have that helps them and their doctors decide if they’re at high enough risk for prostate cancer to consider getting a biopsy. The problem with it as a screening test is that there are way too many false positives (a high PSA value without cancer) and false negatives (a “normal” PSA value but with cancer) that make it a fairly useless (and controversial) screening test.

The “velocity” concept comes into play when the PSA test value is “normal” (i.e. under 4.0), but the absolute value jumps up by more than 75% in one year (say going from 1.0 to 2.0). The study in question determined that the PSA velocity concept lacked validity (in more than 5,000 patients), compared with just checking the absolute value of the PSA itself.

Got that?

I don’t mean to discourage screening (entirely). It’s just that screening tests (like the PSA) are always presented in a way that makes them seem straightforward, when in fact they’re a lot more complicated than that.

Elephant seals near San Simeon

If you like this type of medical skepticism, I strongly recommend Overdiagnosed, the new book by H. Gilbert Welch and his Dartmouth Medical School colleagues, Drs. Lisa Schwartz and Steven Woloshin. They really make you think about the whole process of undergoing medical testing–and hope to make us all much better and more knowledgeable ‘consumers’ of health care. (Perhaps less avid consumers.)

One more noteworthy story from last week:

On the NY Times’ “Well Blog,” Pauline Chen wrote an excellent post titled “What Makes a Hospital Great.”

If you’re an avid reader of GlassHospital, you may find some similarities with what Dr. Chen found and posts that you’ve read here, here, and here.