Tag: measurement

Heterogeneity in Measures of Illness among Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Is Not Explained by Clinical Practice: A Study in Seven U.S. Specialty Clinics

Abstract:

Background: One of the goals of the Multi-site Clinical Assessment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MCAM) study was to evaluate whether clinicians experienced in diagnosing and caring for patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) recognized the same clinical entity.
Methods: We enrolled participants from seven specialty clinics in the United States. We used baseline data (n = 465) on standardized questions measuring general clinical characteristics, functional impairment, post-exertional malaise, fatigue, sleep, neurocognitive/autonomic symptoms, pain, and other symptoms to evaluate whether patient characteristics differed by clinic.
Results: We found few statistically significant and no clinically significant differences between clinics in their patients’ standardized measures of ME/CFS symptoms and function. Strikingly, patients in each clinic sample and overall showed a wide distribution in all scores and measures.
Conclusions: Illness heterogeneity may be an inherent feature of ME/CFS. Presenting research data in scatter plots or histograms will help clarify the challenge. Relying on case–control study designs without subgrouping or stratification of ME/CFS illness characteristics may limit the reproducibility of research findings and could obscure underlying mechanisms.
Source: Unger ER, Lin J-MS, Chen Y, Cornelius ME, Helton B, Issa AN, Bertolli J, Klimas NG, Balbin EG, Bateman L, et al. Heterogeneity in Measures of Illness among Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Is Not Explained by Clinical Practice: A Study in Seven U.S. Specialty Clinics. Journal of Clinical Medicine. 2024; 13(5):1369. https://doi.org/10.3390/jcm13051369 https://www.mdpi.com/2077-0383/13/5/1369 (Full text)

A Mixed Methods System for the Assessment of Post Exertional Malaise in Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Background A central feature of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is post exertional malaise (PEM), which is an acute worsening of symptoms after a physical, emotional and/or mental exertion. PEM is also a feature of Long COVID. Dynamic measures of PEM have historically included scaled questionnaires which have not been validated in ME/CFS. To enhance our understanding of PEM and how best to measure it, we conducted semi-structured qualitative interviews (QIs) at the same intervals as Visual Analog Scale (VAS) measures after a Cardiopulmonary Exercise Test (CPET).

Methods Ten ME/CFS and nine healthy volunteers participated in a CPET. For each participant, PEM symptom VAS (7 symptoms) and semi-structured QIs were administered at six timepoints over 72 hours before and after a single CPET. QI data were used to plot the severity of PEM at each time point and identify the self-described most bothersome symptom for each patient. QI data were used to determine the symptom trajectory and peak of PEM. Performance of QI and VAS data were compared to each other using Spearman correlations.

Results QIs documented that each ME/CFS volunteer had a unique PEM experience, with differences noted in the onset, severity, trajectory over time, and most bothersome symptom. No healthy volunteers experienced PEM. Scaled QI data were able to identify PEM peaks and trajectories, even when VAS scales were unable to do so due to known ceiling and floor effects. QI and VAS fatigue data corresponded well prior to exercise (baseline, r=0.7) but poorly at peak PEM (r=0.28) and with the change from baseline to peak (r=0.20). When the most bothersome symptom identified from QIs was used, these correlations improved (r=.0.77, 0.42. and 0.54 respectively) and reduced the observed VAS scale ceiling and floor effects.

Conclusion QIs were able to capture changes in PEM severity and symptom quality over time in all the ME/CFS volunteers, even when VAS scales failed to do so. Information collected from QIs also improved the performance of VAS. Measurement of PEM can be improved by using a quantitative-qualitative mixed model approach.

Disclaimer This research/work/investigator was supported (in part) by the Division of Intramural Research of the National Institutes of Health, NINDS. The content is solely the responsibility of the author(s) and does not necessarily represent the official views of the National Institutes of Health.

Source: Barbara Stussman, Brice Calco, Gina Norato, Angelique Gavin, Snigdha Chigurupati, Avindra Nath, Brian Walitt. A Mixed Methods System for the Assessment of Post Exertional Malaise in Encephalomyelitis/Chronic Fatigue Syndrome. medRxiv 2023.04.24.23288821;  doi: https://doi.org/10.1101/2023.04.24.23288821 https://www.medrxiv.org/content/10.1101/2023.04.24.23288821v1.full-text (Full text)

Measuring improvement and deterioration in myalgic encephalomyelitis/chronic fatigue syndrome: the pitfalls of the Chalder Fatigue Questionnaire

Adamson et al. considered a 2-point decrease in Chalder Fatigue Questionnaire score to indicate improvement in fatigue and a 2-point increase in Chalder Fatigue Questionnaire score to indicate deterioration in fatigue.1 While intuitively appealing, data exist that suggest a more complex relationship between changes in Chalder Fatigue Questionnaire scores and clinical change.

Collin and Crawley studied treatment outcomes at 11 specialist myalgic encephalomyelitis/chronic fatigue syndrome clinics in England.2 The authors tabulated mean change in Chalder Fatigue Questionnaire score at one year against Clinical Global Impression scores (see additional file 1, table S3). A 2-point decrease in Chalder Fatigue Questionnaire score was reported patients who deemed their health as follows: ‘no change’, ‘a little worse’, ‘much worse’ and ‘very much worse’. The mean changes in Chalder Fatigue Questionnaire score in those categories were similar, with overlapping 95% confidence intervals within the range [4.77, 2.29]. This suggests that a 2-point decrease in Chalder Fatigue Questionnaire score indicates deterioration or no change in the health of a person with myalgic encephalomyelitis/chronic fatigue syndrome, not improvement.

Read the rest of this letter here: https://sci-hub.se/10.1177/0141076820977843

Source: Kirke KD. Measuring improvement and deterioration in myalgic encephalomyelitis/chronic fatigue syndrome: the pitfalls of the Chalder Fatigue Questionnaire. J R Soc Med. 2020 Dec 15:141076820977843. doi: 10.1177/0141076820977843. Epub ahead of print. PMID: 33319615.

Fatigue rating scales: an empirical comparison

Abstract:

BACKGROUND: There has been limited research comparing the efficacy of different fatigue rating scales for use with individuals with chronic fatigue syndrome (CFS). This investigation explored relationships between two commonly-used fatigue rating scales in CFS research, the Fatigue Scale and the Fatigue Severity Scale. Theoretically, these scales have been described as measuring different aspects of the fatigue construct. The Fatigue Scale was developed as a measure of the severity of specific fatigue-related symptoms, while the Fatigue Severity Scale was designed to assess functional outcomes related to fatigue.

METHODS: Associations of these scales with the eight definitional symptoms of CFS and with eight domains of functional disability were examined separately in: (1) an overall sample of individuals with a wide range of fatigue severity and symptomatology; (2) a subsample of individuals with CFS-like symptomatology, and, (3) a subsample of healthy controls.

RESULTS: Findings revealed that both scales are appropriate and useful measures of fatigue-related symptomatology and disability within a general population of individuals with varying levels of fatigue. However, the Fatigue Severity Scale appears to represent a more accurate and comprehensive measure of fatigue-related severity, symptomatology, and functional disability for individuals with CFS-like symptomatology.

 

Source: Taylor RR, Jason LA, Torres A. Fatigue rating scales: an empirical comparison. Psychol Med. 2000 Jul;30(4):849-56. http://www.ncbi.nlm.nih.gov/pubmed/11037093

 

Chronic fatigue syndrome: assessing symptoms and activity level

Abstract:

Current approaches to the diagnosis and assessment of Chronic Fatigue Syndrome (CFS) rely primarily on scales that measure only the occurrence of various symptoms related to CFS. Such approaches do not provide information on either the severity of symptoms or on fluctuations in symptom severity and activity level that occur over time. As a result, these measures do not reflect the complexities and the interrelations among symptoms. By obscuring the fluctuating nature of CFS and its high variability, current assessment procedures may prevent health care professionals from understanding the complexities of this disease. The present study provides two CFS case studies to illustrate the advantages of using self-reporting rating scales in combination with a device used to measure the frequency and intensity of activity. The implications of this assessment system, which captures the symptom dynamics and variability involved in CFS, are discussed.

 

Source: Jason LA, King CP, Frankenberry EL, Jordan KM, Tryon WW, Rademaker F, Huang CF. Chronic fatigue syndrome: assessing symptoms and activity level. J Clin Psychol. 1999 Apr;55(4):411-24. http://www.ncbi.nlm.nih.gov/pubmed/10348404

 

Measuring the functional impact of fatigue: initial validation of the fatigue impact scale

Abstract:

The fatigue impact scale (FIS) was developed to improve our understanding of the effects of fatigue on quality of life. The FIS examines patients’ perceptions of the functional limitations that fatigue has caused over the past month. FIS items reflect perceived impact on cognitive, physical, and psychosocial functioning.

This study compared 145 patients referred for investigation of chronic fatigue (ChF) with 105 patients with multiple sclerosis (MS) and 34 patients with mild hypertension (HT). Internal consistency for the FIS and its three subscales was > .87 for all analyses. Fatigue impact was highest for the ChF group although the MS group’s reported fatigue also exceeded that of the HT group. Discriminant function analysis correctly classified 80.0% of the ChF group and 78.1% of the MS group when these groups were compared.

This initial validation study indicates that the FIS has considerable merit as a measure of patient’s attribution of functional limitations to symptoms of fatigue.

 

Source: Fisk JD, Ritvo PG, Ross L, Haase DA, Marrie TJ, Schlech. Measuring the functional impact of fatigue: initial validation of the fatigue impact scale. Clin Infect Dis. 1994 Jan;18 Suppl 1:S79-83. http://www.ncbi.nlm.nih.gov/pubmed/8148458

 

The measurement of fatigue and chronic fatigue syndrome

Comment in: Chronic fatigue syndrome and heterogeneity. [J R Soc Med. 1992]

 

Fatigue remains as elusive a human experience as ever. At the turn of the century fatigue was almost an obsession of doctors, scientists, writers and even politicians. The scientists believed they could measure it, the doctors they could treat it, the writers describe it, and the politicians prevent it (1). Many confidently expected that fatigue could be eliminated from schools, factories, armies, and even society. That it had to be dealt with was not in doubt, since many authorities believed that if not checked, fatigue, the inevitable consequence of modern life in all its forms, would somehow destroy the nation’s health and its future. Perhaps only the writers achieved their objective (2) – certainly, the descriptions of fatigue and exhaustion in the turn of the century literature, and even in the medical journals, are far richer and detailed than the leaden descriptions which we now encounter.

You can read the rest of this article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1294719/pdf/jrsocmed00112-0007.pdf

 

Source: Wessely S. The measurement of fatigue and chronic fatigue syndrome. J R Soc Med. 1992 Apr;85(4):189-90. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1294719/