Question

1.3 air pollution and birth outcomes, study components. researchers collected data to examine the relationship between air pollutants and preterm births in southern california. during the study air pollution levels were measured by air - quality monitoring stations. specifically, levels of carbon monoxide were recorded in parts per million, nitrogen dioxide and ozone in parts per hundred million, and coarse particulate matter (pm10) in μg/m³. length of gestation data were collected on 143,196 births between the years 1989 and 1993, and air pollution exposure during gestation was calculated for each birth. the analysis suggested that increased ambient pm10 and, to a lesser degree, co concentrations may be associated with the occurrence of preterm births.
(a) identify the main research question of the study.
(b) who are the subjects in this study, and how many are included?
(c) what are the variables in the study? identify each variable as numerical or categorical. if numerical, state whether the variable is discrete or continuous. if categorical, state whether the variable is ordinal.
1.3 (a) is there an association between air - pollution exposure and preterm births? (b) 143,196 births in southern california between 1989 and 1993.
(c) measurements of carbon monoxide, nitrogen dioxide, ozone, and particulate matter less than 10μg/m³ (pm10) collected at air - quality - monitoring stations as well as length of gestation. continuous numerical variables.

Explanation:

Step1: Identify research question

Determine the main inquiry of the study.
The main research question is to examine the relationship between air - pollutants and preterm births.

Step2: Identify subjects and number

The subjects are the 143,196 births between 1989 and 1993 in Southern California.
There are 143,196 subjects.

Step3: Identify variables

The variables include exposure to air - pollutants (PM10, nitrogen dioxide, ozone, carbon monoxide, particulate matter) and whether a birth is preterm or not.
Pollutant variables (PM10, NO2, O3, CO, PM) are numerical and continuous as they are measured in parts per million or similar continuous scales. Preterm birth variable (preterm or not) is categorical.

Step4: Answer part (a)

The main research question is about the association between air - pollutants and preterm births.

Step5: Answer part (b)

The subjects are the 143,196 births in Southern California between 1989 and 1993.

Step6: Answer part (c)

Pollutant variables (PM10, nitrogen dioxide, ozone, carbon monoxide, particulate matter) are numerical and continuous. The preterm birth variable is categorical (preterm or not).

Answer:

(a) The main research question is to determine if there is an association between exposure to air - pollutants (PM10, nitrogen dioxide, ozone, carbon monoxide, particulate matter) and preterm births in Southern California between 1989 and 1993.
(b) The subjects are 143,196 births in Southern California between 1989 and 1993.
(c) Exposure variables (PM10, nitrogen dioxide, ozone, carbon monoxide, particulate matter) are numerical and continuous. The outcome variable (preterm birth: preterm or not) is categorical.