point testing. The revised criteria used a widespread pain index (WPI) and symptom severity scale (SSS) in place of tender point testing under the 1990 criteria. The WPI counts up to 19 general body areas in which the person has experienced pain in the preceding week. The SSS rates the severity of the person's fatigue, unrefreshed waking, cognitive symptoms, and general somatic symptoms, each on a scale from 0 to 3, for a composite score ranging from 0 to 12. The revised criteria for diagnosis were: WPI ≥ 7 and SSS ≥ 5 OR WPI 3–6 and SSS ≥ 9, Symptoms have been present at a similar level for at least three months, and No other diagnosable disorder otherwise explains the pain. American College of Rheumatology 2016 revisions In 2016, the provisional criteria of the American College of Rheumatology from 2010 were revised. The new diagnosis required all of the following criteria: "Generalized pain, defined as pain in at least 4 of 5 regions, is present." "Symptoms have been present at a similar level for at least 3 months." "Widespread pain index (WPI) ≥ 7 and symptom severity scale (SSS) score ≥ 5 OR WPI of 4–6 and SSS score ≥ 9." "A diagnosis of fibromyalgia is valid irrespective of other diagnoses. A diagnosis of fibromyalgia does not exclude the presence of other clinically important illnesses." American Pain Society 2019 In 2019, the American Pain Society in collaboration with the U.S. Food and Drug Administration developed a new diagnostic system using two dimensions. The first dimension included core diagnostic criteria and the second included common features. In accordance to the 2016 diagnosis guidelines, the presence of another medical condition or pain disorder does not rule out the diagnosis of fibromyalgia. Nonetheless, other conditions should be ruled out as the main explaining reason for the patient's symptoms. The core diagnostic criteria are: Multisite pain defined as six or more pain sites from a total of nine possible sites, for at least three months Moderate to severe sleep problems or fatigue, for at least three months Common features found in fibromyalgia patients can assist the diagnosis process. These are tenderness (sensitivity to light pressure), dyscognition (difficulty to think), musculoskeletal stiffness, and environmental sensitivity or hypervigilance. Self-report questionnaires Some research has suggested using a multidimensional approach taking into consideration somatic symptoms, psychological factors, psychosocial stressors and subjective belief regarding fibromyalgia. These symptoms can