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Logo of nihpaAbout Author manuscriptsSubmit a manuscriptHHS Public Access; Author Manuscript; Accepted for publication in peer reviewed journal;
Aust J Prim Health. Author manuscript; available in PMC 2013 June 24.
Published in final edited form as:
Aust J Prim Health. 2010; 16(2): 174–178.
PMCID: PMC3691015

Frequency and Content Analysis of CFS in Medical Text Books


Textbooks are a cornerstone in the training of medical staff and students, and they are an important source of references and reviews for these professionals. The objective of this study was to determine both the quantity and quality of chronic fatigue syndrome (CFS) information included in medical texts. After reviewing 119 medical textbooks from various medical specialties, we found that 48 (40.3%) of the medical textbooks included information on CFS. However, among the 129,527 total pages within these medical textbooks, the CFS content was presented on only 116.3 (.090%) pages. Other illnesses that are less prevalent, such as Multiple Sclerosis and Lyme disease, were more frequently represented in medical textbooks. These findings suggest that the topic of CFS is under-reported in published medical textbooks.

Keywords: Chronic Fatigue Syndrome, medical textbooks, Myalgic Encephalomyelitis


Chronic fatigue syndrome (CFS), also known as Myalgic Encephalomyelitis or Myalgic Encephalopathy (ME), is an illness affecting more than 800,000 Americans (1). According to the Fukuda et al. (2) case definition, individuals diagnosed with CFS must have six or more months of persistent fatigue as well as four or more cardinal symptoms that did not predate the illness (i.e., lymph node pain, sore throat, muscle pain, joint pain, postexertional malaise, new or different headaches, and unrefreshing sleep). The Royal Australian College of Physicans’ (RACP) Guidelines (3) were developed to assist health care professionals diagnose and treat CFS. These Australian Guidelines did indicate that the Fukuda et al. (2) criteria were the “gold standard” for diagnosis, although the RACP and others have also been critical about a number of features of these criteria.

Up to now, there has not been a study on the extent CFS has been portrayed in medical textbooks. According to Rabow et al. (4), medical textbooks are a cornerstone in the training of medical staff and students, and they are an important source of references and reviews for these professionals. For example, the references within medical textbooks play a critical role in providing information to medical professionals on how best to diagnose and treat a variety of illnesses. If the information provided in these textbooks, about particular illnesses is either inadequate or inaccurate, health care professionals might not have the needed information about how to either understand or treat these illnesses.

Biases in the CFS literature have been found in a number of areas. There are about 200 publications each year on CFS in the scientific literature (5), and there have been several literature reviews in the CFS area. Joyce et al. (6) found biases within these literature searches, as authors from laboratory-based disciplines tended to cite laboratory studies, whereas those from psychiatric-based disciplines tended to cite psychiatric references. Goudsmit and Stouten (7) assessed CFS papers published between the years of 1995–2000 in the British Medical Journal, and concluded that many of the articles published during this time were biased towards a school of thought that lacked the immunological and virological aspects of CFS. They also found that researchers publishing in the British Medical Journal were more likely to include the Oxford criteria to define CFS, which is less specific then the Fukuda et al. (2) case definition.

More specifically, Rabow et al. (4) and Carron et al. (8) have identified biases in the information provided in medical textbooks. They found that the amount of information provided in medical textbooks on end-of-life care was minimal. These authors concluded that physicians will not be provided adequate information from medical textbooks for guidance on how to provide care for dying patients. We used these studies as models on textbook content analyses.

There clearly is a need to better understand how CFS is represented in the published literature, particularly within medical textbooks. The present study is the first to evaluate the coverage of CFS in medical textbooks. The objective of this study was to determine both the extent and comprehensiveness of CFS information included in medical textbooks. Based on the bias of CFS in the scientific literature, we predicted that t that CFS would be under-represented when compared to other illnesses.


Textbook Selection

Texts chosen for inclusion were gathered from one university library, two medical school libraries, and one medical school book store. Additionally, we performed online university library searches, and books were then inter-library loaned through DePaul University. We also reviewed several textbooks from a colleague within the Nursing Department at DePaul University. We reviewed a total of 119 textbooks in the following specialty areas: holistic, psychiatry, internal, pediatrics, immune, neurology, pathology, nursing, surgery, nutrition, geriatrics, palliative, endocrinology, obstetrics, and emergency. In some libraries, there were entire sections devoted to certain types of medicine (e.g., surgery, nursing), whereas this was not the case for other types of medicine (e.g., emergency, obstetrics). Consequently, there were fewer books found in some areas that did not have library sections devoted to them. We searched for the most current textbook versions, and in some cases we received them through interlibrary loan or ordered them from the publishers. To begin the analysis process, we inspected the index or table of contents and searched for CFS keywords (i.e., chronic fatigue syndrome, Myalgic Encephalomyelitis and Myalgic Encephalopathy).

After the medical texts were selected, the books were reviewed to determine whether CFS was mentioned in the text. To control for the extent of the CFS coverage on a particular page, each individual page that mentioned CFS was reviewed and the amount of space on the page devoted to CFS was counted as either one-fourth, two-fourths, three-fourths or four-fourths. In other words, the page with CFS on it could be one quarter, one half, three quarters or an entire page of CFS material. If CFS was mentioned, we examined information concerning the illness’ etiology (i.e. psychogenic, biogenic, or the inclusion of both), whether the text reported that there was a high probability of Axis I disorder classification, diagnostic criterion (i.e., 1994 Fukuda or 1988 Holmes criterion), recommended treatment options (i.e. cognitive behavior therapy, graded exercise therapy, anti-depressants, exercise, dietary supplements, relaxation techniques, anti-yeast medication, thyroid medication, non-steroidal anti-inflammatory drugs, corticosteroids, addressing beliefs, and immunotherapy), and prevalence. The reviewers also noted whether or not the text included Myalgic Encephalomyelitis or Myalgic Encephalopathy (ME) terminology, which are alternative names used for CFS in several countries.


Chi-square analysis and ANOVA were employed in this study, using SPSS 1.0 (9) to assess for textbook coverage differences between CFS and several other illness groups. We performed adjusted residuals on the chi-square analysis, and those beyond 2.0 indicate a substantial deviation from what would be expected by chance.


Inter-rater Reliability

Two reviewers independently reviewed 119 textbooks to determine inter-rater reliability. The two reviewers agreed 100% for the number of pages of material on CFS. Inter-rater reliability was 89% for the illness’ etiology, 86% for probability of Axis I disorder classification, 84% for criterion (case definition), 100% for recommended treatment options, 81% for prevalence rate, and 89% for use of the ME term.

Of the 119 medical textbooks from various medical categories, we found that 48 (40.3%) of them included information on CFS (See Table 1). Among the 129,527 total pages within these medical textbooks, CFS content was presented on 116.3 (.09%) pages. Of interest, holistic, psychiatry, and internal based medical texts contained information on CFS in at least half of the published texts. CFS was devoted the largest percentage of total pages in holistic (.22%) and psychiatric (.23) medical textbooks.

Table I
Summary of CFS Representation in Medical Text Books

The results gathered from our analysis (see Table 2) showed that 39 (32.5%) medical texts included content concerning the etiology of CFS. These texts referred to the etiology of CFS as a psychogenic (5.9%), biogenic (14.3%), or both psychogenic and biogenic (14.3%) illness. In addition, 17 (14.3%) of the medical textbooks, reported that DSM-IVAxis I comorbidity commonly occurs in patients with CFS.

Table II
Content Analysis of Texts Including Chronic Fatigue Syndrome (N=119)

The criterion of this illness was included in 25 (21%) textbooks. The Fukuda et al. (2) criteria was the CFS case definition described most frequently in 22 (18.5 %) textbooks. Only 34 (28.6%) of the books provided information on CFS treatment options. The most common treatment options discussed in these texts were cognitive behavior therapy (16%), antidepressants (14.3%), and graded exercise therapy (13.4%).

The prevalence rate for CFS was included in 18 (15.1%) textbooks. Only 19 (16%) of the 119 reviewed medical textbooks had any mention of ME terminology. For 1 of these 19 books, the writers recommended that the term ME should not be used.

Other Medical Illnesses

In an effort to compare the results above to other common medical illnesses, we searched a random sample of 44 of the 119 textbooks, using the same collection methods for CFS data, to determine the number of books and pages that mentioned either cancer, Multiple Sclerosis (MS), diabetes, or Lyme disease (see Table 3; 1, 10,11). We selected illnesses that had higher and lower prevalence rates than CFS, and these prevalence rates are listed in Table 3. CFS is more prevalent than either MS or Lyme disease in the United States, and cancer and diabetes are more prevalent than CFS (1, 10,11). Cancer was mentioned in 68% of books and .97% of pages. Diabetes was mentioned in 89% of books and .92% of pages. Lyme disease was found in 59.8% of books and was on .15% of pages. MS was in 49.5% of textbooks and was on .12% of pages. Finally, CFS was in 22% of these books and .06% of pages.

Table III
Summary of Disease Representation in 44 Medical Text Books with 40,113 pages

There was a significant association between type of illness and the percent mentioned in textbooks (X2= (4, N=228) = 27.13, p<.01). Diabetes was in more books than what would be expected by chance (adjusted residual= 4.7), and CFS was represented in fewer books than would be expected by chance (adjusted residual= 3.2). We also assessed whether the amount of content within books varied by illness types. Using an ANOVA, we first found that Mauchly’s Test of Sphericity was significant (W(9) = .009, p = .00). However, the tests of within-subjects effects were significant using different correction factors (i.e., Greenhouse-Geisser, Huynh-Feldt, Lower-bound); therefore, we report results using Sphericity assumed. There was a significant effect for illness groups (F(4,168) = 13.58, p < .01), and CFS had significantly fewer pages devoted to it than the other illness groups (F(1,42) = 30.32, p < .01).


The major finding of this study is CFS is that under-represented in medical textbooks. Even though 40% of books had some mention of CFS, of the 129,527 pages, there were only 116.3 pages of space provided for CFS. In other words, only .09 percent of pages within medical textbooks currently have any mention of CFS. Of interest, the two specialties with the highest percent of CFS content were holistic medicine and psychiatry (Table 1). Clearly, these findings suggest that CFS is under-reported in published medical textbooks. This is supported by our findings that less prevalent illnesses such as MS and Lyme disease receive more coverage than CFS.

The etiology of CFS was mentioned in 32.5% of the medical textbooks. Of these 39 textbooks, only 12.6% represented both the psychogenic and biogenic etiologies associated with CFS. The majority of texts that mentioned CFS did not include etiology, or they tended to focus either on psychogenic or biological etiology. Similarly, the criterion or case definition was mentioned within only 21% of the texts. Furthermore, within only 15.1% of the text books, prevalence rates for CFS were provided. Overall, these statistics indicate that critical domains within the CFS area are not well represented within medical textbooks.

It is of concern that only 28.6% of textbooks provided any CFS treatment options. Exercise was a commonly suggested treatment option, although patients surveys indicate that it is the form of treatment least favored by patients (12). Also of interest was use of antidepressants, which was the second most common therapeutic option. This might be explained by the fact that psychiatry books provided the second highest percentage of space to CFS.

In addition, illnesses that are less prevalent than CFS were represented more frequently. CFS has a prevalence rate of .42% in the United States (1), yet it received less coverage in medical textbooks than both Lyme disease and MS, which have prevalence rates of .03% (10) and .09% (11), respectively. These results further support the notion that CFS is under-represented in medical textbooks.

In a recent survey conducted by Album and Weston (13), physicians and medical students were asked to create a hierarchy of 38 different illnesses. Album and Weston’s results showed that chronic conditions that have neither a specific body location nor a visible treatment procedure have lower prestige. According to their results, Fibromyalgia (FM) was ranked in prestige last among the 38 diseases. This result is noteworthy because FM is a condition that is closely related to CFS. Low prestige in the eyes of medical professionals may be one of the reasons why CFS is under-represented in medical textbooks.

Patients with CFS have symptoms that are not always visibly apparent, and this might reduce the legitimacy of this illness among some medical personnel (14). The name CFS might also contribute to this problem (15), as this term minimizes the importance of many other severe symptoms such as sore throat, unrefreshing sleep, lymph node, muscle, or joint pain (16). Despite the debate over the use of ME as a replacement term for CFS (14), 84% of medical textbooks did not have any mention of ME terminology.

Another indication of the lack of legitimacy for this illness is that many patients with CFS feel alienated from the health care system. According to Anderson and Ferrans (17), 77% of CFS patients reported they had experienced a negative interaction with a health care provider. Similarly, Twemlow et al. (18) found that 66% of patients with CFS believe that their condition had been made worse after seeking care from their doctors. It is possible that the under-representation of CFS in medical textbooks may lead to some medical personnel either not being knowledgeable or questioning the legitimacy of this illness, and this might be another factor that contributes to alienation that many patients with this illness feel from the health care system.

It is important that healthcare professionals be adequately trained and provided with up-to-date, non-biased information in their textbooks and related course materials. According to Chew-Graham et al. (19), family physicians felt the continuing education and training they received left them unable to diagnose and manage CFS. In a different study, Bowen et al. (20) found that 48% of general practitioners did not feel confident that they could diagnose CFS. These findings are of concern, and these problems might in part be due to under-representation of CFS in medical textbooks.

The present study found that CFS, in contrast to less prevalent illnesses such as Lyme disease and MS, is underrepresented in the medical literature. Medical textbooks might be a critical component in raising CFS awareness, as these authoritative sources of information shape the medical views of health care professionals during their formative years. There is clearly a need for CFS to be better represented in medical textbooks, with more comprehensive coverage provided about etiology, prevalence, criterion, and treatment options. Future research might also be devoted to documenting the number of hours in a medical school courses that are devoted to CFS.


The authors appreciate financial support from NIAID (grant number AI055735).


1. Jason LA, Richman JA, Rademaker AW, Jordan KM, Plioplys AV, Taylor RR. A community-based study of Chronic Fatigue Syndrome. Arch Intern Med. 1999;159:2129–37. [PubMed]
2. Fukuda K, Straus SE, Hickie I, Sharpe MC, Dobbins JG, Komaroff A. The Chronic Fatigue Syndrome: A comprehensive approach to its definition and study. Ann Intern Med. 1994;121:953–9. [PubMed]
3. Loblay R, Stewart G. Chronic fatigue syndrome. Clinical practice guidelines —2002. The Medical Journal of Australia. 2002;176 (9 Suppl):S17–S55.
4. Rabow MW, Hardie GE, Fair JM, McPhee SJ. End-of-life care content in 50 textbooks from multiple specialties. JAMA. 2000;283(6):771–8. [PubMed]
5. Friedberg F, Sohl S, Schmeizer B. Publication trends in Chronic Fatigue Syndrome: Comparisons with Fibromyalgia and fatigue: 1995–2004. J Psychosom Res. 2007;63:143–6. [PubMed]
6. Joyce J, Rabe-Hesketh S, Wessely S. Reviewing the reviews. JAMA. 1998;280(3):264–6. [PubMed]
7. Goudsmit E, Stouten B. Chronic Fatigue Syndrome: Editorial bias in the British Medical Journal. J Chronic Fatigue Syn. 2004;12(4):47–59.
8. Carron AT, Lynn J, Keaney P. End-of-life care in medical textbooks. Ann Intern Med. 1999;130(1):82–6. [PubMed]
9. SPSS Inc. SPSS 14.0 for Windows. Chicago, IL: 2005.
10. [homepage on the Internet] Georgia: Center for Disease Control and Prevention; [updated Jul 30; cited Jul 30]. Available from:
11. Poser CM, Brinar VV. The accuracy or prevalence rates of Multiple Sclerosis: A critical review. Neuroepi. 2007;29:150–5. [PubMed]
12. Cooper L. Perspectives. 2001. Report on survey of members of local ME groups.
13. Album D, Westin S. Do diseases have a prestige hierarchy? A survey among physicians and medical students. Soc Sci Med. 2007 doi: 10.1016/jsocscimed.2007.07.003. [PubMed] [Cross Ref]
14. Jason LA. What’s in a name: Public policy implications of language. Comm Psych. 2007;40(4):35–9.
15. Taylor RR, Friedberg F, Jason LA. A clinician’s guide to controversial illness: Chronic Fatigue Syndrome, Fibromyalgia, and Multiple Chemical Sensitivities. Sarasota, FL: Professional Resource Press; 2001.
16. Jason LA, Corradi K, Torres-Harding S. Toward an empirical case definition of CFS. J Soc Serv Res. 2007;34(3):43–54.
17. Anderson JS, Ferrans CE. The quality of life of persons with chronic fatigue syndrome. J Nerv Ment Dis. 1997;185:359–67. [PubMed]
18. Twemlow SW, Bradshaw SL, Jr, Coyne L, Lerma BH. Patterns of utilization of medical care and perceptions of the relationship between doctor and patient with Chronic Fatigue Syndrome. Psych Reports. 1997;80:643–59. [PubMed]
19. Chew-Graham CA, Cahill G, Dowrick C, Wearden A, Peters S. Using multiple sources of knowledge to reach clinical understanding of Chronic Fatigue Syndrome. Ann Fam Med. 2008;22:389–93. [PubMed]
20. Bowen J, Pheby D, Charlett A, McNulty C. Chronic Fatigue Syndrome: A survey of GPs’ attitudes and knowledge. Fam Pract. 2005;22:389–93. [PubMed]