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

df

variable

-- Explore and understand data
SELECT inter_dom, COUNT(*) AS count_inter_dom
FROM students
GROUP BY inter_dom;

DataFrameas

df

variable

--Filter data for each student type
--International 
SELECT *
FROM students
WHERE inter_dom = 'Inter';

DataFrameas

df

variable

--Domestic
SELECT *
FROM students
WHERE inter_dom = 'Dom';

DataFrameas

df

variable

--Students with unknown status
SELECT *
FROM students
WHERE inter_dom IS NULL;

DataFrameas

df

variable

--Summary statistics of diagnostic scores for all students 
SELECT 
    MIN(todep) AS min_phq,
    MAX(todep) AS max_phq,
    ROUND(AVG(todep), 2) AS average_phq,
    MIN(tosc) AS min_scs,
    MAX(tosc) AS max_scs,
    ROUND(AVG(tosc), 2) AS average_scs,
    MIN(toas) AS min_as,
    MAX(toas) AS max_as,
    ROUND(AVG(toas), 2) AS average_as
FROM students;

DataFrameas

df

variable

--Summarize data for international students
SELECT 
    MIN(todep) AS min_phq,
    MAX(todep) AS max_phq,
    ROUND(AVG(todep), 2) AS average_phq,
    MIN(tosc) AS min_scs,
    MAX(tosc) AS max_scs,
    ROUND(AVG(tosc), 2) AS average_scs,
    MIN(toas) AS min_as,
    MAX(toas) AS max_as,
    ROUND(AVG(toas), 2) AS average_as
FROM students
WHERE inter_dom = 'Inter';

DataFrameas

df

variable

--Impact of length of 
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;