In a randomized controlled clinical trial, the purpose of randomization is to:
Correct Answer D:
Randomization is a process that assigns research participants by chance, rather than by choice, to either the investigational group or the control group of a clinical trial. Each study participant has a fair and equal chance of receiving either the new intervention being studied (by being placed in the investigational group), or of receiving the existing or "control" intervention (by being placed in the control group).
Research participants are randomized in clinical trials so that bias does not weaken the study results. Bias consists of human choices, beliefs or any other factors besides those being studied that can affect a clinical trial's results. If physicians or participants themselves choose the group, assignments might be personally influenced and therefore unevenly slanted toward one side or the other.
For instance, if a study is not randomized, physicians might unconsciously assign participants with a more hopeful prognosis to the experimental group, thus making the new therapy seem more effective than it really is. Conversely, participants with a less hopeful prognosis might pick the experimental treatment, leading it to look less effective than it really is. Randomization prevents such bias. In a randomized trial, investigators use a computer program or a table of random numbers to assign each study participant to a group.
The frequencies most necessary for the understanding of speech extend from about:
Correct Answer B:
The best hearing range for sounds is from around 400 Hz to about 5000 Hz. The lower and higher frequencies require progressively louder sounds for us to hear. The frequency range for audible sound is between 20-20.000 Hz.
Lead exposure typically results in:
Correct Answer C:
Peripheral neuropathy may occur after chronic exposure and is characterized by extensor muscle weakness, particularly in the dominant limb with minimal sensory loss. Lead affects the peripheral and central nervous system. The most common sign of peripheral neuropathy due to chronic lead poisoning is painless wrist drop (weakness of the extensor muscles of hand) which usually develops after many weeks of exposure.
Which of the following ages is most vulnerable to lead poisoning?
Correct Answer A:
Children are at risk for lead toxicity if they live in homes with lead-based paint, if folk remedies are used, or if their parents, siblings, or caregivers are involved in lead-related occupations. Children younger than 3 years are at the greatest risk for lead poisoning. This is because these children are most likely to put things containing lead into their mouths and because their brains are rapidly developing and are most vulnerable to any disorganizing influence. Physicians and other health care professionals must be aware that lead poisoning can occur in children of any age.
A 15-year-old girl comes to the office because she has missed a menstrual period and a home pregnancy test was positive. Bimanual examination discloses an enlarged uterus, and a urine pregnancy test is positive. She is estimated to be approximately 6 to 8 weeks pregnant. You have been the family's physician since she was born. She asks that you please not tell her parents.
Which of the following is the most appropriate immediate response?
Explore with the patient her reasons for not feeling comfortable with sharing this information. In this manner, you can discuss specific reasons for her reluctance to involve her parents, and counsel her appropriately. An attempt to persuade her to share the information with a parent may only exacerbate an already tenuous relationship with her parents.
Explaining that by law you are unable to maintain confidentiality is incorrect. She requires counseling and telling her that you an unable to maintain confidentiality will only make it more difficult for her to trust you. A minor is typically considered to be an “emancipated minor” and capable of making independent medical decisions if they become pregnant or have a sexually transmitted disease, therefore breaching confidentiality is incorrect.
Indicating that she will not be able to hide her pregnancy for long is a nonproductive argument, and does not preempt a discussion. It is a clear breech of doctor-patient confidentiality to reassure, and then notify a parent.
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