Fatigue is a common RA symptom. But, comparing fatigue over time, or between people, is difficult.
With 40% to 80% of people with RA experiencing fatigue, it is crucial to have a validated measure that can distinguish between different symptoms. The Fatigue Severity Scale (FSS) has been designed to distinguish fatigue from clinical depression. Clinical studies have been conducted to ensure this distinction.
The major study on the development of the Fatigue Severity Scale was conducted by Krupp, LB, et. al, and has been cited nearly 3,000 times. In the study, experimenters developed the FSS then subjected it to to tests of:
- Internal consistency
- Whether or not two measures that aim to measure the same construct produce similar scores
- Construct validity is how well the test measure reflects the measure in the real world
What is the Fatigue Severity Scale (FSS)?
The goal of the Fatigue Severity Scale is to ascertain the level of fatigue felt by a person in the last week. Because of this, fatigue scores may change over time — and they likely will for a person struggling with fatigue as a symptom of rheumatoid arthritis.
The Fatigue Severity Scale is made up of 9 statements that are evaluated by the person taking the test. A 7-step, Likert scale is used to rate each response with higher numbers representing stronger agreement by the respondent.
The score of the scale is generated by calculating the average response to the questions.
Sounds confusing… What’s it look like?
Yup. This is one of those where it’s easier just to see it.
- Consider the past week when answering questions
- Choose only one answer for each question
- 1 = Strongly Disagree; 7 = Strongly Agree
How can I take the Fatigue Severity Scale (FSS)?
- Use the RACorner Facebook bot!
- By using the RACorner bot, you can answer the 9 questions in under a minute and get your score automatically. Additionally, we can save your responses and scores for you and provide an export of the data so you can track your fatigue over time to share with your clinicians. And, we can give you reminders so you keep tracking your fatigue!