Which of the following are examples of study designs that apply Hills causal concept of Experiment and Reversibility? You can choose more than one. Counting the number of smokers and non-smokers who get lung cancer.Giving an antioxidant or placebo to people who have smoked many cigarettes for years and measuring DNA mutations in their urine.Measuring DNA mutations in urine from non-smokers and smokers.Measuring DNA mutations in urine from smokers from many countries.Measuring DNA mutations in cord blood from pregnant non-smokers and smokers.
Added by Luc-A L.
Step 1
** Show more…
Show all steps
Your feedback will help us improve your experience
Sri K and 71 other Biology educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
EPIDEMIOLOGY A causal relationship between cigarette smoking and lung cancer was first suspected in the 1920s on the basis of clinical observations. Two studies were conducted by Richard Doll and Austin Bradford Hill in Great Britain. The first was a case-control study begun in 1947 comparing the smoking habits of lung cancer patients with the smoking habits of other patients. The second was a cohort study begun in 1951 recording causes of death among British physicians in relation to smoking habits. This case study deals first with the case-control study, then with the cohort study. Over 1,700 patients with lung cancer, all under age 75, were eligible for the case-control study. About 15% of these persons were not interviewed because of death, discharge, severity of illness, or inability to speak English. An additional group of patients were interviewed but later excluded when initial lung cancer diagnosis proved mistaken. The final study group included 1,465 cases (1,357 males and 108 females). The following table shows the relationship between cigarette smoking and lung cancer among male cases and controls. Table 1. Smoking status before onset of the present illness, lung cancer cases and matched controls with other diseases, Great Britain, 1948-1952. Exposure cases controls Smoker 1350 1296 Non-smoker 7 61 total 1357 1357 Question 1: Calculate the ratio of these odds. Question 2: What do you infer from the odds ratio about the relationship between smoking and lung cancer? Table 2 shows the frequency distribution of male cases and controls by average number of cigarettes smoked per day. Cigarettes/day Cases controls Odds ratio 0 7 61 Referent 1-14 565 706 15-24 445 408 25+ 340 182 All smokers 1350 1296 total 1357 1357 Question 3: Compute the odds ratio by category of daily cigarette consumption, comparing each smoking category to nonsmokers. Question 4: Interpret these results.
Sri K.
Many different study designs are used in epidemiological research. State which study design is being used in each of the scenarios described below and explain your reasoning. Your choices are as follows: *EXPERIMENTAL STUDY *RETROSPECTIVE COHORT STUDY *PROSPECTIVE COHORT STUDY *CASE-CONTROL STUDY *CROSS-SECTIONAL STUDY *ECOLOGICAL STUDY 1) A hospital-based study of antidepressant medication use during pregnancy and the risk of cleft lip in the offspring. Investigators are currently enrolling two groups of women: those who just delivered an infant with a cleft lip and a sample of women who just delivered an infant without any birth defects. The presence or absence of birth defects is based on the newborn physical exam. All mothers are being interviewed to determine their use of antidepressant medications during the pregnancy that just ended. 2) A study of infertility in young adult men after treatment for testicular cancer. Investigators are currently enrolling two groups of men who were treated for cancer between 1990 and 2000: (1) those who were treated with surgery combined with chemotherapy and (2) those who were treated with surgery combined with radiation. The frequency of infertility occurring from the time of treatment through December 2016 is being evaluated in the two groups. 3) A study of the impact of different educational strategies to reduce the consumption of soft drinks among teenagers. The investigators are currently enrolling healthy teens and assigning them to one of two groups: those who view a film on the health risks of soft-drink consumption and those who read printed material on these risks. The frequency of soft drink consumption is being measured at enrollment and six months later. Any changes over time are being compared between the two groups. 4) A study of the impact of needle exchange programs on the transmission of HIV. The needle exchange programs allow drug users to obtain clean needles and syringes free of charge. The investigators are comparing the incidence of new HIV infections in U.S. cities with and without needle-exchange programs. Information on HIV incidence in each city is being obtained from the Centers for Disease Control and Prevention. Information on the presence or absence of needle exchange programs in each city is being obtained from health officials in each city.
Ana Carolina D.
An examination of the medical records of more than 360,000 men showed that those who were overweight or who had high blood pressure had a higher risk of kidney cancer. Which of the following statements is TRUE? Causal inferences can be obtained from this study since it is an observational study. Causal inferences can be obtained from this study since it is an experiment. Causal inferences cannot be obtained from this study since it is an experiment. This is a retrospective study and causal inferences cannot be obtained from this study. This is a prospective study and causal inferences cannot be obtained from this study.
Joanna Q.
Recommended Textbooks
Biology for AP Courses
Objective Biology for NEET
Introduction to General, Organic and Biochemistry
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD