Project: Analyzing Students' Mental Health in SQL

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.

Explore the students data using PostgreSQL to find out if you 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 you may find helpful.

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)

DataFrameas

students

variable

-- Run this code to save the CSV file as students
SELECT * 
FROM 'students.csv';

DataFrameas

df3

variable

SELECT COUNT(*)
FROM students;

SELECT count(inter_dom)
FROM students;

SELECT count(inter_dom)
FROM students
WHERE inter_dom='Inter';

SELECT count(inter_dom)
FROM students
WHERE inter_dom='Dom';

DataFrameas

df1

variable

SELECT
	SUM(todep),SUM(tosc),SUM(toas),
	MAX(todep),MAX(tosc),MAX(toas),
	AVG(todep),AVG(tosc),AVG(toas),
	VARIANCE(todep),VARIANCE(tosc),VARIANCE(toas),
	STDDEV(todep),STDDEV(tosc),STDDEV(toas),
	MIN(todep),MIN(tosc),MIN(toas)
FROM students;

DataFrameas

df2

variable

SELECT
	SUM(todep),SUM(tosc),SUM(toas),
	MAX(todep),MAX(tosc),MAX(toas),
	AVG(todep),AVG(tosc),AVG(toas),
	VARIANCE(todep),VARIANCE(tosc),VARIANCE(toas),
	STDDEV(todep),STDDEV(tosc),STDDEV(toas),
	MIN(todep),MIN(tosc),MIN(toas)
FROM students
WHERE inter_dom='Inter';

DataFrameas

df

variable

-- Find the average scores by length of stay for international students, and view them in descending order
SELECT stay, 
       ROUND(AVG(todep), 2) AS average_phq, 
       ROUND(AVG(tosc), 2) AS average_scs, 
       ROUND(AVG(toas), 2) AS average_as
FROM students
WHERE inter_dom = 'Inter'
GROUP BY stay
ORDER BY stay DESC;