Limited evidence was found for the psychometric properties and clinical usability of these instruments .
However , the CFS-activities and participation question naire ( APQ ) is a disease-specific instrument with moderate content and construct validity .
PURPOSE To summarize measurement instruments used to evaluate activity limitations and participation restrictions in patients with chronic fatigue syndrome ( CFS ) and review the psychometric properties of these instruments .
Chronic fatigue syndrome causes activity limitations and participation restrictions in one or more areas of life .
Functional status in patients with chronic fatigue syndrome, other fatiguing illnesses, and healthy individuals.
BACKGROUND Chronic fatigue syndrome ( CFS ) is a condition that may be associated with substantial disability . The Medical Outcomes Study Short-Form General Health Survey ( SF-36 ) is an instrument that has been widely used in outpatient population s to determine functional status . Our objectives were to describe the usefulness of the SF-36 in CFS patients and to determine if subscale scores could distinguish patients with CFS from subjects with unexplained chronic fatigue ( CF ) , major depression ( MD ) , or acute infectious mononucleosis ( AIM ) , and from healthy control subjects ( HC ) . An additional goal was to ascertain if subscale scores correlated with the signs and symptoms of CFS or the presence of psychiatric disorders and fibromyalgia . DESIGN Prospect ively collected case series . SETTING Patients with CFS and CF were seen in a university-based referral clinic and had undergone a complete medical and psychiatric evaluation . Other study subjects were recruited from the community to participate in research studies . PARTICIPANTS The study included 185 patients with CFS , 246 with CF , 111 with AIM , and 25 with MD . There were 99 HC subjects . MEASURES The  SF-36 and a structured psychiatric interview  were used . The SF-36 contains 8 subscales : physical , emotional , social , and role functioning , body pain , mental health , vitality , and general health- and a structured psychiatric interview .  RESULTS Performance characteristics ( internal reliability coefficients , convergent validity ) of the SF-36 were excellent . A strikingly consistent pattern was found for the physical functioning , role functioning , social functioning , general health , and body pain subscales , with the lowest scores in CFS patients , intermediate scores in AIM patients , and the highest scores in the HC subjects . The CFS patients had significantly lower scores than patients with CF alone on the physical functioning ( P < or = 0.01 ) , role functioning ( P < or = 0.01 ) , and body pain ( P < or = 0.001 ) subscales . The emotional functioning and mental health scores were worst among those with MD . The presence of fibromyalgia , being unemployed , and increasing fatigue severity all were associated with additional functional limitations across multiple functional domains , with increasing fatigue appearing to have the greatest effect . CONCLUSIONS The SF-36 is useful in assessing functional status in patients with fatiguing illnesses . Patients with CFS and CF have marked impairment of their functional status . The severity and pattern of impairment as documented by the SF-36 distinguishes patients with CFS and CF from those with MD and AIM , and from HC , but does not discriminate between CF and CFS
Limited evidence was found for the psychometric properties and clinical usability of these instruments .
However , the CFS-activities and participation question naire ( APQ ) is a disease-specific instrument with moderate content and construct validity .
PURPOSE To summarize measurement instruments used to evaluate activity limitations and participation restrictions in patients with chronic fatigue syndrome ( CFS ) and review the psychometric properties of these instruments .
Chronic fatigue syndrome causes activity limitations and participation restrictions in one or more areas of life .