Comparison of Euroqol EQ-5D and SF-36 in patients with chronic fatigue syndrome

Abstract:

The objective of the study was to compare the Euroqol EQ-5D (Euroqol) and short-form 36 (SF-36) health questionnaires in patients with chronic fatigue syndrome (CFS).

One hundred and twenty-seven outpatients referred to a hospital-based infectious disease clinic with a diagnosis of CFS were contacted by post and asked to complete both questionnaires. Additional data were determined from hospital casenotes. Eighty-five patients returned correctly completed questionnaires.

Euroqol health values and visual analogue scale (VAS) scores were strongly and significantly correlated with all dimensions of the SF-36, with the exception of physical limitation of role. SF-36 dimensions were in turn strongly and significantly correlated with each other, with the same exception.

Patients reported a high degree of physical disability and a moderate degree of emotional or psychological ill-health. The Euroqol elements dealing with mobility and self-care referred to inappropriately severe degrees of disability for these patients with CFS. Similarly some dimensions in the SF-36 were oversensitive and did not discriminate between patients with moderate or severe disability.

It was concluded that Euroqol scores correlated strongly with SF-36 scores and provided useful information about patients with CFS and that Euroqol would be a useful tool for the rapid assessment of health status in CFS. The current Euroqol instrument refers to inappropriately severe degrees of disability for patients with CFS and would need to be modified to be maximally useful in this situation.

 

Source: Myers C, Wilks D. Comparison of Euroqol EQ-5D and SF-36 in patients with chronic fatigue syndrome. Qual Life Res. 1999;8(1-2):9-16. http://www.ncbi.nlm.nih.gov/pubmed/10457734

 

Functional status in patients with chronic fatigue syndrome, other fatiguing illnesses, and healthy individuals

Abstract:

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 populations 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: Prospectively 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.

 

Source: Buchwald D, Pearlman T, Umali J, Schmaling K, Katon W. Functional status in patients with chronic fatigue syndrome, other fatiguing illnesses, and healthy individuals. Am J Med. 1996 Oct;101(4):364-70. http://www.ncbi.nlm.nih.gov/pubmed/8873506

 

Health status in patients with chronic fatigue syndrome and in general population and disease comparison groups

Abstract:

PURPOSE: To measure the functional status and well-being of patients with chronic fatigue syndrome (CFS), and compare them with those of a general population group and six disease comparison groups.

PATIENTS AND METHODS: The subjects of the study were patients with CFS (n = 223) from a CFS clinic, a population-based control sample (n = 2,474), and disease comparison groups with hypertension (n = 2,089), congestive heart failure (n = 216), type II diabetes mellitus (n = 163), acute myocardial infarction (n = 107), multiple sclerosis (n = 25), and depression (n = 502). We measured functional status and well-being using the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), which is a self-administered questionnaire in which lower scores are indicative of greater impairment.

RESULTS: Patients with CFS had far lower mean scores than the general population control subjects on all eight SF-36 scales. They also scored significantly lower than patients in all the disease comparison groups other than depression on virtually all the scales. When compared with patients with depression, they scored significantly lower on all the scales except for scales measuring mental health and role disability due to emotional problems, on which they scored significantly higher. The two SF-36 scales reflecting mental health were not correlated with any of the symptoms of CFS except for irritability and depression.

CONCLUSION: Patients with CFS had marked impairment, in comparison with the general population and disease comparison groups. Moreover, the degree and pattern of impairment was different from that seen in patients with depression.

 

Source: Komaroff AL, Fagioli LR, Doolittle TH, Gandek B, Gleit MA, Guerriero RT, Kornish RJ 2nd, Ware NC, Ware JE Jr, Bates DW. Health status in patients with chronic fatigue syndrome and in general population and disease comparison groups. Am J Med. 1996 Sep;101(3):281-90. http://www.ncbi.nlm.nih.gov/pubmed/8873490