Are you Over-Anxious?

Summarized by Robert W. Griffith, MD
July 3, 2006

Summary

A new simplified questionnaire has been developed to help in the diagnosis of the generalized anxiety disorder, or GAD.

Introduction

It used to be called "Anxiety Neurosis", but now it's "Generalized Anxiety Disorder", or GAD. The name really applies when anxiety about something is exaggerated, unreasonable, or even unreal, to the extent that it interferes with the sufferer's life. As many as 2% to 5% of people in the USA may suffer from GAD, and it rivals depression in its impact on day-to-day living. Unlike depression, however, there is no well-recognized easy measure of GAD that could be useful for assessing the frequency of the disorder, or possible treatments. That has now been remedied; psychiatrists from Columbia University, Indiana University, and the University of Heidelberg have developed a short, simple scale for GAD. It's published in the Archives of Internal Medicine; here's a summary.

What was done

The builders of the new scale selected 9 items from the criteria for GAD listed in the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSMD-IV), along with 4 more items based on reviews of existing anxiety scales. This led to a 13-item questionnaire that asked patients how often they were bothered by each symptom during the previous 2 weeks: "not at all", "several days", "more than half the days", or "nearly every day"; these were scored 0, 1, 2, or 3, respectively. The questionnaire was administered to 2740 patients situated at 15 primary care clinics in the USA.

Of these patients, 965 had a telephone interview with a mental health professional - either a PhD clinical psychologist or a senior psychiatric social worker. The professionals made independent diagnoses with estimates of severity.

The scores of the 13-item questionnaire were compared with the professionals' diagnoses, and the best matching 7 items were selected for the final scale, which was called the GAD-7.

The GAD-7 Anxiety Scale

This questionnaire is set out in the table:

If you checked off any problems, how difficult have these problems made it for you to do your work, take care of things at home, or get along with other people?
Not difficult at all ___
Somewhat difficult ___
Very difficult ___
Extremely difficult ___

Analyses of sensitivity and specificity were done¹. They showed that a score of 10 or more on the GAD-7 represented a reasonable cut point for identifying cases of GAD. The sensitivity at this level was 89%, and the specificity was 82% - quite satisfactory. Cut points of 5, 10, and 15 may be interpreted as representing mild, moderate, and severe levels of anxiety on the GAD-7.

What this scale represents

The GAD-7 scale is a useful tool for identifying probable cases of generalized anxiety disorder. It can also be used to assess the effects of therapy. It's important to know that:
1. Although the average age of the patients who tested the scale was 47, results were similar for men and women older or younger than this age.
2. Using a cut point of 15 ("severe GAD") a prevalence rate of 9% was obtained, which corresponds fairly closely to the prevalence of GAD in primary care in the USA. (The prevalence is the proportion of people having a condition at one point in time).
3. Although some of the symptoms of GAD and depression overlap, the tool was able to distinguish between the two conditions if an additional screen for depression was run.

It must be remembered that GAD is only one anxiety disorder - there are others, such as social phobia, post-traumatic stress disorder, and obsessive/compulsive disorder (OCD).

If you feel tempted to try the GAD-7 on yourself, based on this short article, we advise you to take your result to your family doctor if your score is 10 or above. You may need referral to a specialist, or medication, or just some good advice. Don't try to handle things on your own!

Source

• A brief measure for assessing generalized anxiety disorder. RL. Spitzer, K. Kroenke, JBW. Williams, B. Lowe, Arch Intern Med, 2006, vol. 166, pp. 1092--1097

Footnotes
1. The sensitivity of a test is the proportion of those people who actually have the disease who have a positive test result. When a test has a high sensitivity, a negative result can help rule out the diagnosis. For example, the sensitivity of serum iron measurement for diagnosing iron-deficiency anemia is 90%; therefore if a person does not have a low serum iron, it is highly unlikely that the person has anemia.The specificity of a test is the proportion of people without the disease who have a negative test result. When a test has a high specificity, a positive result 'rules in' the diagnosis. For example, the specificity of a low serum iron level for diagnosing anemia is quite high, at 85%; therefore if a person has a low serum iron, it confirms the diagnosis of iron deficiency anemia.

Related Links
NIMH: General Anxiety Disorder
American Family Physician: GAD
About GAD: a quiz you can take