Chapter 14, Problem 1RQ

Summary Introduction

Introduction: The process of measuring or establishing the connections between the exposure and outcomes is called causal inference.

Answer to Problem 1RQ

Correct answer: “The conclusion in the given case study may be incorrect because of failure to establish the time sequence between onset of the diabetes and diagnosis of pancreatic cancer”.

Hence, the correct answer is option c.

Explanation of Solution

Reason for the correct answer:

Option c. is given as “May be incorrect because of failure to establish the time sequence between onset of the diabetes and diagnosis of pancreatic cancer”.

In a case study with pancreatic cancer patients, comparing to the 4% of well-matched control group who was examined for diabetes 17% of patients found to be diabetic during the time of diagnosis. The conclusion was that diabetes plays an important role in pancreatic cancer.

There are chances for the failure in measuring the beginning of pancreatic cancer and diabetes as different characteristics are studies in the case-control study. The beginning of diabetes can be due to birth or acquired at early forty’s. It is not possible to predict that patients who are suffering from diabetes are in the risk of getting pancreatic cancer.

Hence, the correct answer is option c.

Reasons for incorrect answers:

Option a. is given as, “Is correct”.

In the case control study, various ages, ethnic group, and sex was compared and it is not able to exactly determine the prevalence of diabetes.

Hence, option a. is incorrect.

Option b. is given as, “May be incorrect because there is no control or comparison group”.

In this case study, a control or comparison group is present.

Hence, option b. is incorrect.

Option d. is given as, “May be incorrect because of less complete ascertainment of diabetes in the pancreatic cancer cases”.

There is no less ascertainment in diabetes diagnosis.

Hence, option d. is incorrect.

Option e. is given as, “May be incorrect because of more complete ascertainment of pancreatic cancer in nondiabetic persons”.

There is more ascertainment in diabetes diagnosis.

Hence, option e. is incorrect.

Hence, the options a., b., d., and e. are incorrect.

Conclusion

It is not possible to predict that patients who are suffering from diabetes are in the risk of getting pancreatic cancer.