Depression Screening by PHQ-2 Calculator
Why have we decide to create a depression screening calculator? Due to its increasing prevalence in modern society, depression screening should be an essential part of every doctor's professional life; however it can take a lot of time. Depression screening tools like PHQ-2 are well-validated in scientific literature. This depression screening test uses two simple questions, so you only need to spend 30 seconds on it. In this text, you will learn about depression, its screening, and how to use the depression calculator.
Remember if you suspect that you or one of your friends may suffer from depression - do not hesitate and contact your doctor.
What is depression?
Depression, medically called major depressive disorder, is a prevalent and disabling condition.
People with depression lose the happiness of life and become sad. They often have problems with sleeping well, loose appetite, or feel worthless. Other symptoms include loss of interest, fatigue, slowed movements and speech, and last, but not least, thoughts of death or suicide.
We should remember that certain medical conditions may be the primary source of depressive mood. These include:
Why should we screen for depression?
Depression affects an estimated one in 15 adults (6.7%) in any given year. And one in six people (16.6%) will experience depression at some time in their life.
Globally, depression is responsible for more years lost to disability than any other disease.
This is mainly because so many people suffer from it — approximately 350 million according to the World Health Organization (WHO) — and the fact that it often lasts for many years. Another huge problem associated with it is that it's widely undiagnosed and, therefore, untreated.
Moreover, stigma, lack of effective therapies, and inadequate mental-health resources are another source of depression-related disability. This is why the U.S. Preventive Services Task Force concluded that there is sufficient evidence to recommend periodic screening for depression. However, they did not recommend any specific depression screening test.
About the depression screening calculator (by PHQ-2)
There are plenty of depression screening tools, with different advantages and disadvantages, as well as different sensitivity and specificity. PHQ-2 is a very simple tool, which can help find patients with depressive disorders reliably. It was first published and described in the medical journal Medical Care in the article entitled The Patient Health Questionnaire-2: Validity of a Two-Item Depression Screener. To use the depression screening tool, you need to answer only two questions:
- How often have you had a depressed mood over the last two weeks?
- How often have you felt anhedonia (lack of pleasure) over the last two weeks?
You receive between 0 - 3 points for answering each question. The overall score (the PHQ-2 score) is the sum of the two questions and represents the patients specific risk of having major or any depressive disorder with regards to the average population. Moreover, the PHQ-2 score also tells us about the Positive Predictive Value (PPV) - how probable it is that you really suffer from major or any depressive disorders. You may find detailed information on the PPV percentages for PHQ-2 in the table below:
|PHQ-2 Score||Major Depressive Disorder|
Positive Predictive Value
|Any Depressive Disorder|
Positive Predictive Value
Example of the depression screening test
Now let us show you how to use our depression screening calculator, and what the results mean:
- Answer two simple questions - about your mood and anhedonia.
- Look at the results
- The PHQ-2 Score is your result - if it is three or more you should consult your doctor! You may also find the PPV for this score in the table above.
- Major depressive disorder likelihood ratio - this is your risk of having major depression. If it is below one, it means that your risk is lower than in the general population.
- Any depressive disorder likelihood ratio - this is your risk of having any depression. If it is below one, it means that your risk is lower than in the general population.
- That's it! Isn't it simple?
Let's imagine a guy who is not able to feel pleasure at all, and recently for him everyday has been a bit depressing. He receives 1 + 3 = 4 points- it is his PHQ-2 score. His risk of having major depression is 5.5 times larger than the general population average and the risk of having any kind of depression is 15.7 times greater than general population average!
It means that it is highly probable that he may suffer from depression - he should definitely consult with his doctor!