how does a double blind experiment work

HESI LPN

LPN Nutrition Practice Test

1. How does a double-blind experiment work?

A. Both subject groups take turns receiving each treatment.
B. Neither subjects nor researchers know which subjects are in the control or experimental group.
C. Neither group of subjects knows whether they are in the control or experimental group, but the researchers do not know.
D. Both subject groups know whether they are in the control or experimental group, but the researchers do not know.

Correct answer: B

Rationale: The correct answer is B. In a double-blind experiment, neither the subjects nor the researchers know which subjects are in the control or experimental group. This helps to eliminate bias and ensure that the results are more objective. Choice A is incorrect as in a double-blind experiment, subjects do not take turns receiving each treatment; it is about masking the treatment allocation. Choice C is incorrect because it implies that the researchers are aware of the group allocation, which goes against the principle of blinding in a double-blind study. Choice D is incorrect as both subject groups should not know whether they are in the control or experimental group to maintain the blindness of the study.

2. What is a common symptom of a respiratory infection in infants?

A. Wheezing
B. High appetite
C. Increased thirst
D. Lethargy

Correct answer: A

Rationale: Wheezing is a common symptom of respiratory infections in infants, often associated with coughing and difficulty breathing. It occurs due to the narrowing of the airways. Choice B, 'High appetite,' is incorrect as respiratory infections usually lead to a decrease in appetite rather than an increase. Choice C, 'Increased thirst,' is incorrect as it is not a typical symptom of a respiratory infection in infants. Choice D, 'Lethargy,' can be a symptom of respiratory infections but is not as specific and common as wheezing.

3. What is the primary intervention for a child experiencing a tonic-clonic seizure?

A. Administer intravenous fluids
B. Place the child in a prone position
C. Protect the child from injury
D. Perform mouth-to-mouth resuscitation

Correct answer: C

Rationale: The primary intervention for a child experiencing a tonic-clonic seizure is to protect them from injury. Placing the child in a prone position can be dangerous as it may lead to further harm due to the risk of aspiration or airway obstruction. Administering intravenous fluids is not recommended during a seizure. Performing mouth-to-mouth resuscitation is also not indicated as the child will resume breathing spontaneously after the seizure stops. Ensuring the child's safety and preventing injury by removing harmful objects and cushioning their head is essential until the seizure subsides.

4. How should a healthcare professional handle a child with a new diagnosis of ADHD?

A. Provide behavioral therapy and support
B. Increase sugar intake
C. Restrict all forms of exercise
D. Avoid medication use

Correct answer: A

Rationale: When dealing with a child newly diagnosed with ADHD, providing behavioral therapy and support is crucial. This approach helps the child learn coping strategies, improve social skills, and manage their symptoms effectively. Choice B, increasing sugar intake, is incorrect as there is no evidence linking sugar consumption to ADHD. Choice C, restricting all forms of exercise, is inappropriate as regular physical activity can actually benefit children with ADHD by helping them release excess energy and improve focus. Choice D, avoiding medication use, may not be the best course of action as medication prescribed by a healthcare professional can sometimes be beneficial in managing ADHD symptoms when combined with other therapies.

5. How should a healthcare professional address the concerns of parents about their child’s developmental delay?

A. Recommend immediate diagnostic testing
B. Suggest waiting for natural development
C. Provide information about early intervention services
D. Advise on increasing physical activity

Correct answer: C

Rationale: When addressing concerns about a child's developmental delay, providing information about early intervention services is crucial as it can facilitate timely support and resources. This option helps parents understand the available support systems and interventions for their child. Recommending immediate diagnostic testing may cause unnecessary anxiety without first exploring other supportive options. Suggesting waiting for natural development could result in missed opportunities for early intervention that are crucial for improving developmental outcomes. Advising on increasing physical activity is not directly related to addressing developmental delays and does not address the core issue of developmental delay.