Question
Determine whether the following study described is observational or an experiment. If the study is an experiment, identify the control and treatment groups, and discuss whether single- or double-blinding is necessary. If the study is observational, state whether it is a retrospective study, and if so, identify the cases and controls.
A national institute's study of 723 melanoma patients and 1017 cancer-free patients matched by age, sex, and race found that those having a single large mole had twice the risk of melanoma. Having 10 or more moles was associated with a 12 times greater risk of melanoma.
The study is
A. Observational
B. An experiment
A national institute's study of 723 melanoma patients and 1017 cancer-free patients matched by age, sex, and race found that those having a single large mole had twice the risk of melanoma. Having 10 or more moles was associated with a 12 times greater risk of melanoma.
The study is
A. Observational
B. An experiment
Answers
Answered by
GPT-4o mini
The study described is:
**A. Observational**
This is because the researchers are observing and comparing the characteristics of melanoma patients with those of cancer-free patients without manipulating any variables or assigning treatments.
Since it's an observational study, we should identify whether it is a retrospective study. In this case, the study is indeed retrospective, as it looks back at past data regarding patients' moles and their subsequent cancer diagnoses.
**Cases and Controls:**
- **Cases**: The 723 melanoma patients.
- **Controls**: The 1017 cancer-free patients matched by age, sex, and race.
In summary, this study is observational and retrospective, with cases being the melanoma patients and controls being the cancer-free patients.
**A. Observational**
This is because the researchers are observing and comparing the characteristics of melanoma patients with those of cancer-free patients without manipulating any variables or assigning treatments.
Since it's an observational study, we should identify whether it is a retrospective study. In this case, the study is indeed retrospective, as it looks back at past data regarding patients' moles and their subsequent cancer diagnoses.
**Cases and Controls:**
- **Cases**: The 723 melanoma patients.
- **Controls**: The 1017 cancer-free patients matched by age, sex, and race.
In summary, this study is observational and retrospective, with cases being the melanoma patients and controls being the cancer-free patients.