91Ó°ÊÓ

Researchers Sally Tracy and associates undertook a cross-sectional study looking at the method of delivery and cost of delivery for first-time "low risk" mothers under three delivery scenarios: (1) Caseload midwifery (2) Standard hospital care (3) Private obstetric care The results of the study revealed that \(58.5 \%\) of all births with midwifery were vaginal deliveries compared with \(48.2 \%\) of standard hospital births and \(30.8 \%\) of private obstetric care. In addition, the costs of delivery from midwifery was \(\$ 3903.78\) compared with \(\$ 5279.23\) for standard hospital care and \(\$ 5413.69\) for private obstetric care. Source: Sally K Tracy, Alec Welsh, Donna Hartz, Anne Lainchbury, Andrew Bisits, Jan White, and Mark Tracy "Caseload midwifery compared to standard or private obstetric care for first time mothers in a public teaching hospital in Australia: a cross sectional study of cost and birth outcomes" BMC Pregnancy and Childbirth 2014,14:46 (a) Why is this a cross-sectional observational study? (b) Name the explanatory variable in the study. (c) Name the two response variables in the study and determine whether each is qualitative or quantitative.

Step by step solution

01

- Understanding Cross-Sectional Observational Study

Cross-sectional studies observe a specific population at a single point in time or over a short period. This study assesses different delivery methods (midwifery, standard hospital care, private obstetric care) and their associated outcomes (vaginal deliveries and costs) at one point in time, without manipulating variables, hence it is observational.

02

- Identifying the Explanatory Variable

The explanatory variable is the variable that explains or causes changes in the response variable. In this study, it is the method of delivery (midwifery, standard hospital care, private obstetric care).

03

- Identifying the Response Variables

Response variables are outcomes or effects observed in the study. Here, the response variables are the type of delivery (vaginal or not) and the cost of delivery. The type of delivery is a qualitative variable (categorical: vaginal or not), and the cost of delivery is a quantitative variable (numerical: amount of money).

Unlock Step-by-Step Solutions & Ace Your Exams!

• Full Textbook Solutions

  Get detailed explanations and key concepts

• Unlimited Al creation

  Al flashcards, explanations, exams and more...

• Ads-free access

  To over 500 millions flashcards

• Money-back guarantee

  We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

explanatory variable

In research, understanding the role of the explanatory variable is crucial. An explanatory variable, also known as an independent variable, is the one that researchers believe causes a change or effect in another variable. In Sally Tracy's study, the explanatory variable is the method of delivery.
There are three methods assessed: Caseload midwifery, Standard hospital care, and Private obstetric care. This variable is presumed to influence the outcomes observed. By defining the method of delivery as the explanatory variable, researchers can then focus on understanding how it impacts the outcomes, like the type of delivery and cost.
Remember, the explanatory variable is what we manipulate or categorize to see its effect on other aspects of the study. In observational studies, we don't actively manipulate it but instead observe its natural occurrences and consequences.

response variable

The response variable, also known as the dependent variable, is what researchers measure to see if it is affected by changes in the explanatory variable. It represents the outcome of interest.
In this study, there are two response variables:

• Type of delivery
• Cost of delivery

The type of delivery indicates whether the birth was a vaginal delivery or not, making it a categorical or qualitative variable. This means it falls into distinct categories without any numerical value.
The cost of delivery, on the other hand, is a quantitative variable. It is measured in terms of money, providing a numerical assessment of the expense associated with each method of delivery.
By focusing on these response variables, researchers aim to understand the differences and potential impacts of each method of delivery on these important outcomes.

qualitative vs quantitative variables

In studies, it's important to distinguish between qualitative and quantitative variables as they require different analytical methods. Here’s how they differ:

• Qualitative variables: These are also known as categorical variables. They describe a quality or characteristic that can be grouped into categories. For example, in Tracy’s study, the type of delivery (vaginal or not) is a qualitative variable. It categorizes deliveries into distinct groups without numerical significance.
• Quantitative variables: These variables measure quantities and are numerical. They can be counted or measured and often can be plotted on a graph. In the given study, the cost of delivery is a quantitative variable. It represents a measurable amount of money spent on each delivery method.

Understanding whether a variable is qualitative or quantitative is crucial because it determines how data will be collected, analyzed, and interpreted.