Does going to university in a different country affect your mental health? A Japanese international university surveyed its students in 2018 and published a study the following year that was approved by several ethical and regulatory boards.
The study found that international students have a higher risk of mental health difficulties than the general population, and that social connectedness (belonging to a social group) and acculturative stress (stress associated with joining a new culture) are predictive of depression.
Exploring the students dataset using PostgreSQL to determine whether I would come to a similar conclusion for international students and see if the length of stay is a contributing factor.
Here is a data description of the columns that may be helpful for the analysis.
| Field Name | Description |
|---|---|
inter_dom | Types of students (international or domestic) |
japanese_cate | Japanese language proficiency |
english_cate | English language proficiency |
academic | Current academic level (undergraduate or graduate) |
age | Current age of student |
stay | Current length of stay in years |
todep | Total score of depression (PHQ-9 test) |
tosc | Total score of social connectedness (SCS test) |
toas | Total score of acculturative stress (ASISS test) |
-- Run this code to save the CSV file as students
SELECT *
FROM 'students.csv';The following are the exploratory steps.
I start by counting all of the records in the dataset.
SELECT COUNT(*)
FROM 'students.csv';Then, I count all records perstudent type to see how the records are categorized and scored.
SELECT inter_dom, COUNT(inter_dom) AS count_inter_dom, COUNT(*) AS total_records
FROM 'students.csv'
GROUP BY inter_dom;There are 201 records are international and 67 are domestic. However, the table also has 18 with NULL value.
Next, I will filter the data to see how it differs between the students types.
SELECT *
FROM 'students.csv'
WHERE inter_dom = 'Inter';SELECT *
FROM 'students.csv'
WHERE inter_dom = 'Dom';SELECT *
FROM 'students.csv'
WHERE inter_dom IS NULL;As we can see with international student type, we have students are in both undergraduate and graduate academic levels with age range is from 17 to over 30. On the other hand, students who do not study aboard are all undergraduate students, and all of them are under 30.
With NULL records, there are clearly no valuable information.
I am going to find the summary statistics of the diagnostic tests for all students.
SELECT 'Average', ROUND(AVG(todep),2) AS 'Score of depression (PHQ-9 test)', ROUND(AVG(tosc), 2) AS 'Score of social connectedness (SCS test)', ROUND(AVG(toas), 2) AS 'Score of acculturative stress (ASISS test)'
FROM 'students.csv'
UNION
SELECT 'Standard deviation', ROUND(STDDEV(todep), 2) AS 'Score of depression (PHQ-9 test)', ROUND(STDDEV(tosc), 2) AS 'Score of social connectedness (SCS test)', ROUND(STDDEV(toas),2) AS 'Score of acculturative stress (ASISS test)'
FROM 'students.csv'
UNION
SELECT 'Max', MAX(todep) AS 'Score of depression (PHQ-9 test)', MAX(tosc) AS 'Score of social connectedness (SCS test)', MAX(toas) AS 'Score of acculturative stress (ASISS test)'
FROM 'students.csv'
UNION
SELECT 'Min', MIN(todep) AS 'Score of depression (PHQ-9 test)', MIN(tosc) AS 'Score of social connectedness (SCS test)', MIN(toas) AS 'Score of acculturative stress (ASISS test)'
FROM 'students.csv';I am going to repeat the summary statistics steps but this time only applies to international students.