Patients diagnosed with atrial fibrillation (AF) develop depression with episode
ID: 3173971 • Letter: P
Question
Patients diagnosed with atrial fibrillation (AF) develop depression with episodes of anxiety, which makes a negative impact on their quality of life. Even though there is a relationship between AF diagnosis and patients’ episodes of anxiety and quality of life found from previous studies, there is not enough research study done on the reason why this happens. Nonetheless, depression is reported as the strongest independent predictor to impair quality of life in these patients.
To use a retrospective cohort design in which we first locate a group of subjects with AF and identify which are suffering from depression and which are not. Here a diseased group is determined first and is retrospectively assessed for exposure status. Then, we consider another group of subjects which are in some sense comparable but who do not have AF and identify who are suffering from depression and who are not.
What type of sampling would you use for your study (considering the design you have chosen of course) and why?
Explanation / Answer
Answer:
For the given scenario we have to select the two groups of the patients with atrial fibrillation (AF) and patients without atrial fibrillation (AF). Here, we have to select the two separate samples of patients and then we have to select the patients from these samples who develop depression and who not develop depression. This means we need to use the two stage sampling. At the first stage we will use the random sampling method for the selection of patients if the population size is big. Also, note that, we need to use convenience sample of patients if population size is not adequate. For the second stage of each selected two samples, we need to use convenience sample because we would not get the information of the depression or quality of life without convening the patients. Here, we would use 2X2 completely randomized design for this study.
I
II
A
Patients with AF & depression
Patients with AF & without depression
B
Patients without AF & depression
Patients without AF & without depression
I
II
A
Patients with AF & depression
Patients with AF & without depression
B
Patients without AF & depression
Patients without AF & without depression