Randomization, Placebos, Blinding or "Run-in-period"?

Randomization, Placebos, Blinding or "Run-in-period"?

1.) An ecological study is one that examines a group as a unit of analysis--- True or false? 2.) An ecologic comparison study is sometimes called a cross-sectional ecological...

Two students took the same courses last year. Each received the following final grades. In evaluating the grades, student 2 claims that it is a tie, while student 1 says he has a better grade. Who...

consider the following dataset (3,3,3,3,4,4,4,4,5,6,6,6,8,8,9,10,11,12,13)(I already put it in order). Find: a. Mode, median, mean b. The minimum, maximum, three quartiles, IQR, variance,...

Suppose you want a confidence level of 99% and your margin of error is 1%. Please calculate how big you sample size should be? Assume the population you are going to sample from has the highest variation...

The office of Student health at a local college decides to take a survey to better understand the students' mental health needs and whether the college has met such needs. Given limited time and resources,...

A study of 200 out-patients visiting a hospital during the past year showed that on average the waiting time to see a physician was 30 minutes. Please answer the following questions: a. What is...

From our class, (20 females, 15 males), four students are to be chosen to form a committee. In how many different ways can the student be chosen such that there would be at least one female?

A hospital conducts a survey of patients' satisfaction with its service. Each survey respondent ranks the 3 items with which he/she is most satisfied with the hospital service. The items to be ranked...

The professor did not explain ratios to anyone and refuses to help with this homework.

A medicine is developed to lower blood pressure for hypertensive patients. The clinical test shows that the drug has better effects on males and females. It lowers the blood pressure to male patients...

A doctor is in the habit of measuring blood pressure twice. She notices that patients who are unusually high on the first reading tend to have somewhat lower second readings. She concludes that patients...

A publisher prints 300 words per page in its books. Historically the publisher has found that authors make, on average, one typo every 250 words: 1.How many typos would you expect to find...

Assume the average weight of a full-term newborn infant (i.e. 39-40 weeks gestation) in the US is 3400g. Suppose we measure the birth weight of 1000 (full-term) infants born to alcoholic mothers....

Prior to the initiation of a rubella immunization program in a metropolitan county, a survey revealed that 55 out of a sample of 100 elementary school children in the county had been immunized against...

Find the mean and stand deviation?

a recent study reported that the prevalence of obesity is 45% in children ages 6-12. If 15 children were analyzed what is the probability that 7 are obese?

A study was conducted to evaluate the effect of calcium supplement on preventing postmenopausal osteoporosis. Among 300 women aged 60 and above who took calcium supplements regularly, 15% had postmenopausal...

I am trying to examine the powering for a study using response rate as a endpoint. Normally I convert to Cohen's d and determine power from there, how come when I convert the odds ratio...

A randomized research study is designed to determine whether albuterol by nebulization improves pulmonary function in children with bronchiolitis. Twenty chidren, ten of whom receive albuterol and...

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