Correctly that the treatment and control groups do not differ with respect to outcome.   That the treatment and control groups do not differ with respect to outcome when in fact they do.   That you don’t have sufficient information to present results.

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If 20% of inactive controls had been misclassified as active?  f 10 % of inactive cases had been misclassified as active?

In a study of schizophrenia (a mental disorder including disorganization of thought and withdrawal from reality), researchers looked at the prevalence of the disorder in the biological and adoptive parents of people who were adopted as children; they found the following results: Prevalence of schizophrenia Adoptees With schizophrenia Biological parents Adoptive parents 12 2 Without schizophrenia 6 4 [Source: S. S. Kety et al., 1978, in The Nature of Schizophrenia: New Approaches to Research and Treatment, L. C. Wynne, R. L. Cromwell, and S. Matthysse, Eds. New York: Wiley, 1978, pp. 25-37.] What can you conclude from these results concerning the role of genetics in schizophrenia? Explain your reasoning.

Consider a study designed to estimate the role that certain characteristics play on predicting persons who are at greatest risk of developing arthritis in one or more joints. The authors have noted a lost-to-followup rate of 26%. Why is this cause for concern?   It is cause for concern because those who remain in the study may be at a systematically higher risk than those not followed   It is not cause for concern in this type of study; the concern exists only for randomized trials   It is cause for concern because those who remain in the study may be at a systematically higher or lower risk than those not followed   It is cause for concern because those who remain in the study may be at a systematically lower risk than those not followed

An early study found that postal workers who worked in the office had higher rates of coronary heart disease than those who delivered mail on foot. The investigators concluded that physical activity is inversely related to risk of developing coronary heart disease. Sceptics disagreed, pointing out that the postal clerks were older than the postal carriers, and that age is a risk factor for coronary heart disease. This argument highlights the possible role of: -Chance? -Selection bias? -Recall bias? -Confounding?

An inter-strand grouping of students is working on a study about the Copper-infused materials utilization for real environment viruses and bacteria to address good health and well-being of the target beneficiaries. They want to compare the utilization and non-utilization of copper infused materials if it will yield the same results when introduced to reduce bacterial contamination. QUESTION: Will the choice of sampling technique affect the statistical test to be used? Also, what is the appropriate statistical test to use and why?

I'm having trouble finding the dependent and independent variables of this scenaro:  Average IQ scores for young school children are known to be 100 (SD = 15).  However, the literature indicates that children’s intelligence may be decreased if their mothers have German measles during pregnancy.  Using hospital records, a researcher obtained a sample of n = 25 school children whose mothers all had German measles during their pregnancies.  Do the data indicate that children born to mothers who had German measles during the pregnancy have significantly lower IQ scores than typical young school children?

In regard to the difference margin (M), which of the following statements is NOT right? a. the difference margin should be chosen before the start of a trial  b. the difference margin is a value randomly chosen by the researchers c. the difference margin is carefully chosen with both statistical and clinical considerations  d. Non-inferiority and equivalence in efficacy between a new treatment and the standard treatment should be claimed in the presence of a well justified difference margin

In a research topic related to COVID-19 and Handwashing, who would be the target population and why?