Tag: screening tests

Too Much Information!

Some people would like to manage their own health care without having to depend on a doctor. They consult Google, diagnose themselves, and treat themselves. The Do-It-Yourself trend in lab tests continues apace. Without a doctor’s order, patients can get legitimate and/or questionable lab tests directly from various companies such as Any Lab Test Now and Doctor’s Data (which has sued Stephen...

/ April 23, 2013

True Informed Consent Is Elusive

Most of us would agree that doctors should not treat patients without their consent, except in special cases like emergency care for an unconscious patient.  It’s not enough for doctors to ask “Is it OK with you if I do this?” They should get informed consent from patients who understand the facts, the odds of success, and the risk/benefit ratio of treatments....

/ November 20, 2012

Re-thinking the Annual Physical

Please note: the following refers to routine physicals and screening tests in healthy, asymptomatic adults. It does not apply to people who have been diagnosed with diseases, who have any kind of symptoms or signs, or who are at particularly high risk of certain specific diseases. Throughout most of human history, people have consulted doctors (or shamans or other supposed providers of...

/ February 21, 2012

Virtual Colonoscopy Can Be Hazardous to Your Health

The US Preventive Services Task Force (USPSTF) recommends that everyone aged 50-75 be screened for colon cancer with any one of three options: colonoscopy every 10 years, flexible sigmoidoscopy every 5 years, or fecal occult blood testing (FOBT) every year. Conventional colonoscopy is considered the “gold standard” since it allows for direct detection and biopsy of early cancers and removal of precancerous...

/ June 28, 2011

Overdiagnosis

Dr. H. Gilbert Welch has written a new book Over-diagnosed: Making People Sick in the Pursuit of Health, with co-authors Lisa Schwartz and Steven Woloshin.  It identifies a serious problem, debunks medical misconceptions and contains words of wisdom. We are healthier, but we are increasingly being told we are sick. We are labeled with diagnoses that may not mean anything to our health....

/ February 1, 2011

Questioning Colonoscopy

Everybody knows that colonoscopy is the best test to screen for colorectal cancer and that colonoscopies save lives. Everybody may be wrong. Colonoscopy is increasingly viewed as the gold standard for colorectal cancer screening, but its reputation is not based on solid evidence. In reality,  it is not yet known for certain whether colonoscopy can help reduce the number of deaths from...

/ February 16, 2010

Screening Tests – Cumulative Incidence of False Positives

It’s easy to think of medical tests as black and white. If the test is positive, you have the disease; if it’s negative, you don’t. Even good clinicians sometimes fall into that trap. Based on the pre-test probability of the disease, a positive test result only increases the probability by a variable amount. An example: if the probability that a patient has...

/ June 30, 2009