27 Oct Ecologic, cross-sectional, case-control, retrospective cohort or prospective cohort.

For each of the descriptions below, identify the one study design that fits. Choose only one study design per description: ecologic, cross-sectional, case-control, retrospective cohort or prospective cohort.

A study was done to determine risk factors for female-to-female non-intimate violence.  Women who had reported to the emergency department of three participating hospitals because of pain or damage inflicted intentionally by an unrelated woman were compared to women who reported to the same emergency departments for other health problems on a variety of potential risk factors. 

Two hundred babies were followed from birth to age five to determine if those whose mothers smoked during pregnancy were more likely to have respiratory infections in the first five years of life than those whose mothers did not smoke during pregnancy. The findings supported the investigators’ assumption that smoking during pregnancy increases the frequency of respiratory infections in young children. 

A survey was conducted in which the height, weight, level of alcohol consumption, and blood pressure in a sample of men and women aged 30-59 were measured. 

A study was designed to find out if high rates of tuberculosis were associated with high rates of AIDS in a population.  The prevalence of tuberculosis in 50 countries was correlated with the prevalence of AIDS in those same countries. 

In 1981 the physical examination records of the incoming first-year class of 1935 at the University of Minnesota were examined to see whether the freshmen’s recorded height and weight at the time of admission to the university were related to their risk of developing coronary heart disease by 1981. 

A cohort was assembled and questioned about fruit and vegetable intake at baseline.  They were then followed for 5 years after which time the incidence of colorectal cancer was determined by the amount of fruit and vegetable intake they had earlier reported. 

A group of 300 adults who had been diagnosed with cancer were compared with 600 other adults without any cancer on their respective histories of alcohol consumption. 

A study was conducted to investigate the association between maternal education and birth defects based on data abstracted from birth certificates. 

A study was conducted to examine the pattern of mortality rates from influenza over time throughout the 20th century in the United States. Cause-specific mortality rates for every flu season beginning in 1900-1901 and ending in 2003-2004 (with the exception of 1905-1909, for which data could not be located) were assembled and compared.  With the exception of the 1918-1919 flu season, the pattern was a definitely decreasing secular trend throughout the 20th and early 21st centuries. 

Fifty patients recently diagnosed with hepatitis A were selected along with another 50 patients without hepatitis A from among those attending a local clinic.  The participants in the two groups were then examined to determine if they had had any body piercing within the last two months. 

One hundred forty thousand and fifty-seven women aged 50-79 years old were followed for an average of 7.7 years, during which time 269 incident cases of renal cell carcinoma (cancer of the kidney) were identified.  High central adiposity (waist to hip ratio) at the start of the study was found to be an important risk factor for this type of cancer. 

The incidence and mortality rates from breast and prostate cancer were compared among 100 major cities around the world.  Cities in relatively low latitudes had low incidence and mortality rates of these cancers, while cities in higher latitudes had higher rates. 

Women with and without type 2 diabetes were compared on the location of body fat (hips versus waist). 

In the year 2,000, the records of 8,047 white male smelter workers, believed to have been exposed to high quantities of arsenic, were gathered for those who began work between 1938 and 1963.  Death certificates were examined to ascertain the cause of death for this group up until 2,000.  They were compared to death certificates from the workers in other occupations of the same race, gender and time period.  Higher rates of mortality from respiratory cancer and heart disease were found among those who had worked at least 15 years as smelter workers. 

A sample of 6,465 people over the age of 55 were followed for an average of 9.4 years to determine if the incidence of Parkinson’s Disease was related to cholesterol levels at the start of the study. 

In 2010 a survey was conducted of 1,656 adults in New York City.  The investigators used questionnaires to collect self-reported health information, measured blood pressure, and obtained sodium, potassium and creatinine values from urine samples.  They found evidence of higher sodium intake among non-Hispanic blacks and Hispanics than among non-Hispanic whites.

In 1945 there were 1,000 women who worked in a factory, painting radium dials on watches.  In 1976 an investigator compared the incidence of bone cancer in these women up to 1975 with that of 1,000 women who worked as telephone operators in 1945.  Twenty of the radium dial painters and four of the telephone operators developed bone cancer between 1945 and 1975. 

Incidence rates of gonorrhea and rates of premature death before age 65 were correlated with a high percentage of boarded up houses in 107 U.S. cities.

The prevalence of genital infection with chlamydia trachomatis among women of childbearing age was ascertained in a survey of Houston.

In 2002 the computerized records of 1,099 children from an urban pediatric practice in New Orleans born between April 1, 1998 and June 1, 1999 were examined.  It was found that 568 had been vaccinated against rotavirus infection, while 513 had not.  Hospital records were also reviewed to determine rates of hospitalization for rotavirus infections in this group of children between October 1998 and June 2001. The attack rate (incidence) of rotavirus hospitalization was 0.34 per 100 child-years for the entire sample. It was 0.52 for unvaccinated (no doses) children, 0.20 for partially vaccinated (one or two doses) children and 0 for fully vaccinated (three doses) children.