Which of these statements is correct based on published reports?

Which of these is correct regarding cross-sectional studies?

The lowest reported use of opioids is in the

All samples selected from a population by SRS must have had an equal chance of being selected.

The average midyear population of Smalltown is 15,000. During the period from Jan 1 to Oct 1, there were 126 automobile accidents from January to June, 215 from June to August, and 76 from September to October 1st. What is the period prevalence rate for automobile accidents per 1,000 population?

The world’s largest ongoing health survey is the

Which of these is a major motivation for women to use methamphetamines?

Prevalence rate is equal to:

The rapid identification of a bioterrorist event depends on syndromic surveillance

Which of these is an independent variable in the model of deterministic causality.