Answer: The Center for disease control and prevention (CDC) uses the Body Mass Index(BMI) to determine categories of overweight and at risk for being overweight
Explanation: BMI is defined as the body mass of an individual divided by the square of their height.
The BMI is used to categorize a person as underweight, normal weight, overweight, or obese based on the ratio of their body mass to the square of their height.
Underweight are categorised to have a BMI of under 18.5, normal weight has a range of 18.5 to 25, overweight has a range of 25 to 30, and obese over 30. The unit for the BMI is the kg/m²
Answer:
Content validity
Explanation:
Your friend, Tania, is asking your advice on her new study design. She is conducting a study on whether milk chocolate consumption prior to a memory task will improve recall performance as compared to consuming white chocolate. She decides to include three participants in each group. You tell her that she should likely have more participants or she will lack <u>content</u> validity. Content validity has to do with whether your research subjects or respondents are representative of all aspect of your research construct. Increasing the sample size or the number of replicates per treatment increases the construct validity by increasing the degree of freedom and reducing experimental error. Increasing the sample size will make the study a more representation of the entire study population.
The concrete operational stage
I believe the answer is: b. allow efficient gathering of unobservant phenomena
Survey is conducted by letting the subject to fill up a set of questionaires by their own without the supervision of the researchers. Because of this, gathering needed information became extremely efficient since it can be conducted with very little labor resource and could take up large number of population.
