Question

In March 2012, two patients - a 39-year-old man (Patient 1) and a 36-year-old woman (Patient 2) - presented at a hospital in Queens, NY with symptoms of vomiting followed by dysphagia, diplopia, dysarthria, dyspnea, and difficulty walking. Neurologic examination of Patient 1 (who arrived on March 12^th) revealed bilateral cranial nerve deficits: dilated pupils minimally reactive to light, ptosis, oculomotor palsy, and facial paralysis. He was admitted to the intensive-care unit. Electromyography studies eventually were determined to be suspicious for, but not diagnostic of, botulism. Botulinum toxin type B was identified by bioassay in fecal specimens. Examination of Patient 2, (who arrived at the hospital on March 28, 2012), was conducted by the same clinicians who had cared for Patient 1, and who by this time had laboratory confirmation of botulism in patient 1. They immediately suspected botulism because of the similar clinical presentation, and admitted Patient 2 to the hospital. Electromyography studies were determined to be suspicious for, but not diagnostic of, botulism, and no botulinum toxin was detected in serum or fecal specimens for Patient 2. Both patients improved and were discharged. Further investigation by the New York City Department of Health revealed that both patients had purchased fresh tofu from the same grocery store in Queens in January 2012, and each had prepared home-fermented tofu using similar recipes. Similar fermentation practices at the two homes might have facilitated toxin production. Testing confirmed botulinum toxin type B in home-fermented tofu consumed by patient 1. Bulk tofu at the grocery in Queens was found to be sold in unrefrigerated, uncovered, water-filled bins. Traceback revealed that the grocery's fresh bulk tofu supplier at the time of the patients' purchases had gone out of business. DOHMH advised the grocery's manager of the need to properly store bulk tofu. Public health responders and clinicians should be aware of the association between botulism and fermented tofu.

Question 8:

What type of study design was this? (4 points)

Question 9:

In general, what is the primary importance of this type of study to population health science? (4 points)

Question 10:

What is the biggest limitation of this type of study design? (4 points)

Answer 1

Solution 8:

Design of quantitative research mostly deals with the reflection of a deterministic thought that is rooted in the postpositivism. This phenomenon typically adopts the philosophy that originality could be identified although in a probabilistic sense. Further the research design approach is typically deductive in which relationship between or among the variables is tested. Hence, the results obtained are based on careful observation and interpretation of objects. Quantitative research design is classified into non-experimental and experimental designs. Non experimental designs typically used to describe or examine association of variables. There is no random assignment, no control groups, or changes in variables, as this research design is used for observation only. The most common non-experimental designs are descriptive or correlational studies.

In the present case, there was no control group identified and the systematic investigation of the characteristics between the two patients has been evaluated. A further explanatory question includes ‘How’ and ‘Why’ has been generated during the process. Moreover a typical relationship has been established between the two patients that successfully justify the present design as a correlational design under non experimental research design.

Solution 9:

The primary importance of this type of study design is of making considerable positive predictions and understanding the prevalence. Further correlational research design is generally used to inform casual/informal inferences and the practice based on evidence based.

Solution 10:

The most important limitation of correlational research design includes unable to draw the conclusion based on the evidence or relationship between the variables as there might be the presence of third variable that are not been taken care of.