You are counseling an adolescent patient about the long-term management of her asthma while she is away at college. She brought an article she found on the Internet that promotes an herbal supplement purported to be a “safe, natural” treatment for asthma. You recall a recent study in the medical literature showing inhaled steroids to be statistically superior to the advertised herbal supplement at preventing asthma exacerbations at the p < 0.05 level. You explain to her that this means which of the following?
- The inhaled steroids are 5% better than herbal treatment
- A critical threshold for medical significance has been reached
- Patients will not benefit from the herbal treatment 5% of the time
- The odds are less than 1 in 20 that the differences observed were only a chance variation
- It would be unethical to use herbal treatment’
the answer is below…
The United States Medical Licensing Examination, or USMLE for short, is a three-part licensing examination that is required in order to receive a license to practice medicine within the United States.
The USMLE assesses a physician’s ability to apply knowledge, concepts, and principles, and to determine fundamental patient-centered skills that are important in health and disease and that constitute the basis of safe and effective patient care.Examination committees composed of medical educators and clinicians from across the United States and its territories prepare the examination materials each year.
This exam is designed by the Federation of State Medical Boards and the National Board of Medical Examiners to determine whether or not an individual understands and can apply the knowledge necessary to practice medicine safely and intelligently.
The USMLE is actually comprised of three different exams that are referred to as steps, which examine the individual’s knowledge of specific topics related to the field of medicine such as basic science, medical knowledge, medical skills, clinical science, and the application of all of these skills and areas of knowledge in the medical field.
All three steps of the USMLE include a series of computerized multiple-choice questions, but the format of the exam and the information covered in each multiple-choice section is different for each step of the USMLE. The USMLE Step II also has a clinical skills portion that examines an individual’s ability to work with real patients and the USMLE Step III has a computerized patient simulation portion in addition to the multiple-choice section of the exam. In order for an individual to receive a license to practice medicine, the individual must pass all three steps of the USMLE.
The answer is d, The odds are less than 1 in 20 that the differences observed were only a chance variation.
The probability given is an estimation of the odds that the observed differences could have occurred by chance alone. More precisely, assuming one therapy was no different than the other (relative risk = 1.0, termed the null hypothesis), the p-value is the probability of obtaining an association as strong or stronger than the one observed. Typically, the p-value most often selected in the medical literature to test for “statistical significance” is .05; the smaller the p-value, the “more significant” the result. The interpretation of these results depends on an assessment of factors, such as the study design, the size of the sample, the type of controls used, the severity of the disease, the side effects, and the importance of the treatment. The tendency for negative results to remain unpublished should also be kept in mind.