Leonard Jason

Leonard A. Jason is a professor of psychology at DePaul University in Chicago, Illinois, USA. He is an ME/CFS patient and runs the Chronic Fatigue Syndrome Project at DePaul University.

Leonard Jason was profiled in the New York Times in 2011 by David Tuller.

Awards

 * 2011, Rudy Perpich Senior Lectureship Award, presented to a distinguished CFS/FM scientist, physician or healthcare worker awarded by IACFS/ME

Open Letter to The Lancet
Two open letters to the editor of The Lancet urged the editor to commission a fully independent review of the PACE trial, which the journal had published in 2011. The first, written in 2015, was sign by Dr. Jason and 5 of his colleagues. In 2016, thirty-six additional colleagues in the ME/CFS field, signed the second letter.
 * 13 November 2015, An open letter to Dr. Richard Horton and The Lancet
 * 10 February 2016, An open letter to The Lancet, again - Virology blog

Studies

 * 2016, Mortality in patients with myalgic encephalomyelitis and chronic fatigue syndrome
 * 2016, Deconstructing [[post-exertional malaise]: An exploratory factor analysis.] "'Abstract: Post-exertional malaise is a cardinal symptom of myalgic encephalomyelitis and chronic fatigue syndrome. There are two differing focuses when defining post-exertional malaise: a generalized, full-body fatigue and a muscle-specific fatigue. This study aimed to discern whether post-exertional malaise is a unified construct or whether it is composed of two smaller constructs, muscle fatigue and generalized fatigue. An exploratory factor analysis was conducted on several symptoms that assess post-exertional malaise. The results suggest that post-exertional malaise is composed of two empirically different experiences, one for generalized fatigue and one for muscle-specific fatigue.'"
 * 2016, Assessing current functioning as a measure of significant reduction in activity level "Abstract - Background: Myalgic encephalomyelitis and chronic fatigue syndrome have case definitions with varying criteria, but almost all criteria require an individual to have a substantial reduction in activity level. Unfortunately, a consensus has not been reached regarding what constitutes substantial reductions. One measure that has been used to measure substantial reduction is the Medical Outcomes Study Short-Form-36 Health Survey (SF-36). Purpose: The current study examined the relationship between the SF-36, a measure of current functioning, and a self-report measure of the percent reduction in hours spent on activities. Results: Findings indicated that select subscales of the SF-36 accurately measure significant reductions in functioning. Further, this measure significantly differentiates patients from controls. Conclusion: Determining what constitutes a significant reduction in activity is difficult because it is subjective to the individual. However, certain subscales of the SF-36 could provide a uniform way to accurately measure and define substantial reductions in functioning.
 * 2016, The Role of Infectious and Stress-related Onsets in Myalgic Encephalomyelitis and Chronic Fatigue Syndrome Symptomatology and Functioning
 * 2016, Educational Priorities for Healthcare Providers and Name Suggestions for Chronic Fatigue Syndrome: Including the Patient Voice
 * 2016, qEEG / LORETA in Assessment of Neurocognitive Impairment in a Patient with Chronic Fatigue Syndrome: A Case Report (Marcie Zinn, Mark Zinn, Leonard Jason)
 * 2016, Case definitions integrating empiric and consensus perspectives
 * 2016, Comparing the DePaul Symptom Questionnaire with physician assessments: a preliminary study"'Results: The DSQ identified 60 and the physicians identified 56 as having a CCC diagnosis. The overall agreement between the two ratings on the diagnostic assessment part was moderate (Kappa = 0.45, p < .001). The sensitivity of DSQ was good (98%) while the specificity was 38%. Positive and negative predictive values were 92% and 75%, respectively. Conclusion: DSQ is useful for detecting and screening symptoms consistent with a CCC diagnosis in clinical practice and research. However, it is important for initial screening of self-report symptoms to be followed up by subsequent medical and psychiatric examination in order to identify possible exclusionary medical and psychiatric disorders.'"
 * 2016, Housebound versus nonhousebound patients with myalgic encephalomyelitis and chronic fatigue syndrome"'Abstract - Objectives: The objective of this study was to examine individuals with myalgic encephalomyelitis and chronic fatigue syndrome who are confined to their homes due to severe symptomatology. The existing literature fails to address differences between this group, and less severe, nonhousebound patient populations. Methods: Participants completed the DePaul Symptom Questionnaire, a measure of myalgic encephalomyelitis and chronic fatigue syndrome symptomology, and the SF-36, a measure of health impact on physical/mental functioning. ANOVAs and, where appropriate, MANCOVAS were used to compare housebound and nonhousebound patients with myalgic encephalomyelitis and chronic fatigue syndrome across areas of functioning, symptomatology, and illness onset characteristics. Results: Findings indicated that the housebound group represented one quarter of the sample, and were significantly more impaired with regards to physical functioning, bodily pain, vitality, social functioning, fatigue, post-exertional malaise, sleep, pain, neurocognitive, autonomic, neuroendocrine, and immune functioning compared to individuals who were not housebound. Discussion: Findings indicated that housebound patients have more impairment on functional and symptom outcomes compared to those who were not housebound. Understanding the differences between housebound and not housebound groups holds implications for physicians and researchers as they develop interventions intended for patients who are most severely affected by this chronic illness.'"
 * The Relationship between Age and Illness Duration in Chronic Fatigue Syndrome"'Abstract:Chronic fatigue syndrome (CFS) is a debilitating illness, but it is unclear if patient age and illness duration might affect symptoms and functioning of patients. In the current study, participants were categorized into four groups based upon age (under or over age 55) and illness duration (more or less than 10 years). The groups were compared on functioning and symptoms. Findings indicated that those who were older with a longer illness duration had significantly higher levels of mental health functioning than those who were younger with a shorter or longer illness duration and the older group with a shorter illness duration. The results suggest that older patients with an illness duration of over 10 years have significantly higher levels of mental health functioning than the three other groups. For symptoms, the younger/longer illness duration group had significantly worse immune and autonomic domains than the older/longer illness group. In addition, the younger patients with a longer illness duration displayed greater autonomic and immune symptoms in comparison to the older group with a longer illness duration. These findings suggest that both age and illness duration need to be considered when trying to understand the influence of these factors on patients."
 * 2015, Myalgic Encephalomyelitis: Symptoms and Biomarkers. (Marcie Zinn, Mark Zinn, Leonard Jason)
 * 2015, Functional level of patients with chronic fatigue syndrome reporting use of alternative vs. traditional treatments
 * 2015, Chronic fatigue syndrome versus systemic exertion intolerance disease
 * 2015, Variability in symptoms complicates utility of case definitions. Abstract
 * 2015, Comparing and contrasting consensus versus empirical domains. Abstract
 * 2015, Test–retest reliability of the DePaul Symptom Questionnaire Abstract"'Methods: Test–retest reliability of the measure was examined with a sample of 26 adults self-identifying as having either ME/CFS, ME, and/or CFS and 25 adults who did not self-identify as having these illnesses and were otherwise healthy controls. Results: Overall, the majority of items on the DSQ exhibited good to excellent test–retest reliability, with Pearson's or kappa correlation coefficients that were 0.70 or higher.'"
 * 2014, Validating a measure of myalgic encephalomyelitis/chronic fatigue syndrome symptomatology. Abstract"'Methods: Exploratory factor analysis (EFA) was used to establish the underlying factor structure of the DePaul Symptom Questionnaire (DSQ) using a well-characterized sample of individuals (92.6% met the Fukuda et al. criteria and/or the Clinical Canadian Criteria) and this structure was then tested on a less stringently recruited sample of individuals utilizing a confirmatory factor analysis (CFA). Convergent and discriminant validity of the DSQ were also examined utilizing alternative measures of symptomatology and functioning. Results: A three-factor solution was found using EFA (Neuroendocrine, Autonomic, and Immune Symptoms; Neurological/Cognitive Dysfunction; Post-Exertional Malaise) and the fit of this factor structure was adequate for the second sample. The DSQ was found to have good convergent and discriminant validity. Conclusions: The DSQ is a valid tool for assessing ME/CFS symptoms. There may be two core ME/CFS symptom clusters: post-exertional malaise and cognitive dysfunction.'"
 * 2014, Chronic Fatigue Syndrome: The Current Status and Future Potentials of Emerging Biomarkers. Abstract
 * 2013, Energy conservation/envelope theory interventions. Full Text
 * 2012, Minimum data elements for research reports on CFS.
 * 2008, The Energy Envelope Theory and myalgic encephalomyelitis/chronic fatigue syndrome. (Full text)
 * 2006, "A Pediatric Case Definition for Myalgic Encephalomyelitis and Chronic Fatigue Syndrome""'Summary: For a diagnosis of chronic fatigue syndrome (CFS), most researchers use criteria that were developed by Fukuda et al. (1994), with modifications suggested by Reeves et al. (2003). However, this case definition was established for adults rather than children. A Canadian Case Definition (ME/CFS; Myalgic Encephalomyelitis/CFS) has recently been developed, with more specific inclusion criteria (Carruthers et al., 2003). Again, the primary aim of this case definition is to diagnose adult CFS. A significant problem in the literature is the lack of both a pediatric definition of ME/CFS and a reliable instrument to assess it. These deficiencies can lead to criterion variance problems resulting in studies labeling children with a wide variety of symptoms as having ME/CFS. Subsequently, comparisons between articles become more difficult, decreasing the possibility of conducting a meta-analysis. This article presents recommendations developed by the International Association of Chronic Fatigue Syndrome Pediatric Case Definition Working group for a ME/CFS pediatric case definition. It is hoped that this pediatric case definition will lead to more appropriate identification of children and adolescents with ME/CFS.'"
 * 2006, Causes of death among patients with chronic fatigue syndrome
 * 2003, Identification of ambiguities in the 1994 chronic fatigue syndrome research case definition and recommendations for resolution
 * 2001, Assessing attitudes toward new names for chronic fatigue syndrome."'Abstract: A questionnaire was distributed at the American Association of Chronic Fatigue Syndrome's biannual convention in Washington in January 2001 as well as through various Internet Web sites and listserves during early February and March of 2001. The sample consisted of 432 respondents. Most respondents (86%) indicated they wanted a name change, although more patients than scientists were in favor of this change. It was also apparent that the patients and physicians were clearly split between adopting a name such as myalgic encephalopathy versus one such as neuro-endocrine immune disorder. Also, among those respondents who selected either of these two choices for a new name, less than 30% of them supported the other name. Although the majority of respondents feel the name should be changed at this time, this survey suggests there are different stakeholders involved in the name-change process, each with strong and sometimes disparate feelings about changing the name.'"
 * 2000, Chronic fatigue syndrome: sociodemographic subtypes in a community-based sample.

Talks & Interviews

 * 2016, 12th International IACFS/ME Biennial Clinical and Research Conference, Emerging Science and Clinical Care, Behavioral Assessment and Treatment of ME/CFS and Fibromyalgia(Workshop given with Fred Friedberg, Ph.D.)
 * Oct 2015, Defining essential features of myalgic encephalomyelitis and chronic fatigue syndrome (Sweden)]
 * 2015, DePaul Chili Challenge video

Invest in ME International ME Conference

 * 2010, Speaker at the 5th Invest in ME International ME Conference on Key Note Speech: How Case Definitions Can Stigmatize: Implications for Epidemiology, Etiology, and Pathophysiology DVD available
 * 2008, Speaker at the 3rd Invest in ME International ME Conference on Case Definitions of ME/CFS – including paediatric case definition DVD available

ME/CFS Alert

 * 2011, ME/CFS Alert Episode 10 - Dr. Leonard Jason, Pt. 3
 * 2011, ME/CFS Alert Episode 09 - Dr. Leonard Jason, Pt. 2
 * 2011, ME/CFS Alert Episode 08 - Dr. Leonard Jason, Pt. 1

Web seminars Science for Patients / Wetenschap voor patienten (The Netherlands, english spoken, dutch subtitles)

 * 2014, 50. Introduction - Experience with ME / Introductie - Ervaring met ME Prof. Leonard Jason


 * 2014, 51. Criteria and Diagnosis part 1 / Criteria en diagnose deel 1 - Prof. Leonard Jason


 * 2014, 52. Criteria and Diagnosis part 2 / Criteria en diagnose deel 2 - Prof. Leonard Jason


 * 2014, 53. ME versus Psychiatric Disorders / ME versus psychiatrische aandoeningen - Prof. Leonard Jason


 * 2014, 54. Treating and managing ME / Behandelen van en omgaan met ME -Prof. Leonard Jason


 * 2014, 55. Symptoms of ME and treatments / Symptomen van ME en behandelingen - Prof. Leonard Jason


 * 2014, 56. Population and Social Impact / Populatie en sociale gevolgen - Prof. Leonard Jason


 * 2014, 57. Future and Teachibg about ME / Toekomst en onderwijs geven over ME - Prof. Leonard Jason

Books

 * 2003, The Handbook of Chronic Fatigue Syndrome by Leonard Jason, Patricia Fennell and Renée R. Taylor.
 * 1998, Understanding Chronic Fatigue Syndrome: An Empirical Guide to Assessment and Treatment, by Fred Friedberg and Leonard Jason

Online Presence

 * Website
 * Twitter

Learn More

 * Wikipedia - Leonard Jason
 * Leonard Jason's Home Page at DePaul University