On 2014 Feb 05, Tom Kindlon commented:

A CFS study which raises questions about the use of the Role Emotional (RE) subscale of the SF-36 to define CFS

(This was originally posted here: http://www.biomedcentral.com/1472-6963/3/25/comments but the formatting has been lost and some people may read the paper on PubMed Central)

As I mentioned in the previous comment, this paper recommends, amongst other questionnaires, the use of the SF-36 questionnaire but does not specify which subscales should be used.

One group of researchers[1] have decided to use the physical function, role physical, social function and role emotional subscales of the SF-36 to define disability, with a low score on just one of these subscales being sufficient to satisfy the criteria (i.e. there didn't need to be more than one low scores).

Since then, this definition has gone on to be used in numerous papers (such as [2-5]) as the CDC are using it as the definition they're using for their CFS studies in the US, and they probably have the largest CFS research program in the world. It was used to give the prevalence rate of 2.54% for CFS in the adult population[6]. Most recently, it was used to investigate the prevalence of the reporting of childhoold trauma in this cohort[7].

A study by Fulcher and White (2000)[8] raises questions about the use of the Role Emotional (RE) subscale of the SF-36 to select patients with CFS. The study involved 66 patients with CFS without a current psychiatric disorder, 30 healthy but sedentary controls, and 15 patients with a current major depressive disorder.

It found, amongst other things, that "the two patient groups were significantly more incapacitated than the sedentary controls on all SF-36 measures (p<0.001), except that the patients with CFS were not significantly different in emotional or mental function." Also, "the depressed subjects were significantly more incapacitated in emotional and mental functioning than the patients with CFS p<0.001)."

These results suggest that low scores on the emotional and mental functioning subscales of the SF-36 do not seem to be an intrinsic part of CFS (if they're found, they could be related to comorbid psychiatric issues). They also points out the risks of using the RE subscale alone [especially given CFS shares some characteristics with depression and so some people with depression (but not CFS) could potentially score the required 25 points on the Symptom Inventory] i.e. one could inadvertently include some people who have depression but not CFS, as CFS patients.

References

[1] Reeves WC, Wagner D, Nisenbaum R, Jones JF, Gurbaxani B, Solomon L, Papanicolaou DA, Unger ER, Vernon SD, Heim C. Chronic Fatigue Syndrome – A clinically empirical approach to its definition and study. BMC Medicine 2005, 3:19<br><br>

[2] Raison CL, Lin JM, Reeves WC. Association of peripheral inflammatory markers with chronic fatigue in a population-based sample. Brain Behav Immun. 2008 Dec 11.

[3] Welberg LA, Capuron L, Miller AH, Pagnoni G, Reeves WC. Neuropsychological performance in persons with chronic fatigue syndrome: results from a population-based study.Majer M, Psychosom Med. 2008 Sep;70(7):829-36.

[4] Nater UM, Youngblood LS, Jones JF, Unger ER, Miller AH, Reeves WC, Heim C. Alterations in diurnal salivary cortisol rhythm in a population-based sample of cases with chronic fatigue syndrome. Psychosom Med. 2008 Apr;70(3):298-305.

[5] Nater UM, Maloney E, Boneva RS, Gurbaxani BM, Lin JM, Jones JF, Reeves WC, Heim C. Attenuated morning salivary cortisol concentrations in a population-based study of persons with chronic fatigue syndrome and well controls. J Clin Endocrinol Metab. 2008 Mar;93(3):703-9.

[6] Reeves WC, Jones JF, Maloney E, Heim C, Hoaglin DC, Boneva RS, Morrissey M, Devlin R. Prevalence of chronic fatigue syndrome in metropolitan, urban, and rural Georgia. Popul Health Metr. 2007 Jun 8;5:5.

[7] Heim C, Nater UM, Maloney E, Boneva R, Jones JF, Reeves WC. Childhood trauma and risk for chronic fatigue syndrome: association with neuroendocrine dysfunction. Arch Gen Psychiatry. 2009 Jan;66(1):72-80.

[8] Fulcher KY, White PD. Strength and physiological response to exercise in patients with chronic fatigue syndrome. J Neurol Neurosurg Psychiatry. 2000 Sep;69(3):302-7.

On 2014 Feb 03, Tom Kindlon commented:

Which subscales of the SF-36 should be used? Results from a study in Fibromyalgia patients

(This was originally posted here: http://www.biomedcentral.com/1472-6963/3/25/comments but the formatting has been lost and some people may read the paper on PubMed Central)

This paper recommends, amongst other questionnaires, the use of the SF-36 questionnaire. But which subscales should be used? One group of researchers[1] decided to use the physical function, role physical, social function and role emotional subscales of the SF-36 to define disability, with a low score on just one of these subscales being sufficient to satisfy the criteria (i.e. there didn't need to be more than one low scores). Since then, this definition[1] has gone on to be used in numerous papers (for example, 2-5).

But is this a good way of using the SF-36 given the Fukuda definition for CFS[6] requires that there be a "substantial reduction in previous levels of occupational, educational, social, or personal activities".

Fibromyalgia patients share many similarities with CFS patients and many researchers use CFS and FMS patients together in their studies (for example [7-10]).

One study[11] recently assessed Fibromyalgia Syndrome (FS) patients using the SF-36 questionnaire. It found that patients could be broken down into two groups using the SF-36 subscales looking at mental well-being (social functioning, role limitation due to emotional health problems, and mental health). "One group demonstrated psychological dysfunction, whereas the other showed normal psychological scores. Physical well-being scores (physical functioning, role limitation due to physical health problems, bodily pain, general health, and vitality) did not differ between FS patients but were altogether below the normal range."

If this was found to be the same in other populations, it would suggest that perhaps including patients who solely have low scores on subscales assessing mental well-being such as the role emotional and social functioning subscales of SF-36, which is all the CFS definition prepared by Reeves[1] requires, would select a group of people with psychological dysfunction but not necessarily greater physical disability.

References:

[1] Reeves WC, Wagner D, Nisenbaum R, Jones JF, Gurbaxani B, Solomon L, Papanicolaou DA, Unger ER, Vernon SD, Heim C. Chronic Fatigue Syndrome – A clinically empirical approach to its definition and study. BMC Medicine 2005, 3:19

[2] Reeves WC, Heim C, Maloney EM, Youngblood LS, Unger ER, Decker MJ, Jones JF, Rye DB. Sleep characteristics of persons with chronic fatigue syndrome and non-fatigued controls: results from a population-based study. BMC Neurology 2006, 6:41

[3] Majer M, Jones JF, Unger ER, Youngblood LS, Decker MJ, Gurbaxani B, Heim C, Reeves WC. Perception versus polysomnographic assessment of sleep in CFS and non-fatigued control subjects: results from a population-based study. BMC Neurology 2007, 7:40

[4] Jones JF, Maloney EM, Boneva RS, Jones AB, Reeves WC. Complementary and alternative medical therapy utilization by people with chronic fatiguing illnesses in the United States. BMC Complementary and Alternative Medicine 2007, 7:12

[5] Reeves WC, Jones JF, Maloney E, Heim C, Hoaglin DC, Boneva RS, Morrissey M, Devlin R.Prevalence of chronic fatigue syndrome in metropolitan, urban, and rural Georgia. Popul Health Metr. 2007 Jun 8;5:5.

[6] 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 Int Med 1994, 121:953-959.

[7] Teitelbaum JE, Johnson C, St Cyr J. The use of D-ribose in chronic fatigue syndrome and fibromyalgia: a pilot study. J Altern Complement Med. 2006 Nov;12(9):857-62.

[8] Glass JM. Cognitive dysfunction in fibromyalgia and chronic fatigue syndrome: new trends and future directions. Curr Rheumatol Rep. 2006 Dec;8(6):425-9.

[9] Zachrisson O, Regland B, Jahreskog M, Jonsson M, Kron M, Gottfries CG. Treatment with staphylococcus toxoid in fibromyalgia/chronic fatigue syndrome--a randomised controlled trial. Eur J Pain. 2002;6(6):455-66.

[10] Zachrisson O, Regland B, Jahreskog M, Kron M, Gottfries CG. A rating scale for fibromyalgia and chronic fatigue syndrome (the FibroFatigue scale). J Psychosom Res. 2002 Jun;52(6):501-9.

[11] Oswald J, Salemi S, Michel BA, Sprott H. Use of the Short-Form-36 Health Survey to detect a subgroup of fibromyalgia patients with psychological dysfunction. Clin Rheumatol. 2008 Apr 1

On 2014 Feb 03, Tom Kindlon commented:

Which subscales of the SF-36 should be used? Results from a study in Fibromyalgia patients

(This was originally posted here: http://www.biomedcentral.com/1472-6963/3/25/comments but the formatting has been lost and some people may read the paper on PubMed Central)

This paper recommends, amongst other questionnaires, the use of the SF-36 questionnaire. But which subscales should be used? One group of researchers[1] decided to use the physical function, role physical, social function and role emotional subscales of the SF-36 to define disability, with a low score on just one of these subscales being sufficient to satisfy the criteria (i.e. there didn't need to be more than one low scores). Since then, this definition[1] has gone on to be used in numerous papers (for example, 2-5).

But is this a good way of using the SF-36 given the Fukuda definition for CFS[6] requires that there be a "substantial reduction in previous levels of occupational, educational, social, or personal activities".

Fibromyalgia patients share many similarities with CFS patients and many researchers use CFS and FMS patients together in their studies (for example [7-10]).

One study[11] recently assessed Fibromyalgia Syndrome (FS) patients using the SF-36 questionnaire. It found that patients could be broken down into two groups using the SF-36 subscales looking at mental well-being (social functioning, role limitation due to emotional health problems, and mental health). "One group demonstrated psychological dysfunction, whereas the other showed normal psychological scores. Physical well-being scores (physical functioning, role limitation due to physical health problems, bodily pain, general health, and vitality) did not differ between FS patients but were altogether below the normal range."

If this was found to be the same in other populations, it would suggest that perhaps including patients who solely have low scores on subscales assessing mental well-being such as the role emotional and social functioning subscales of SF-36, which is all the CFS definition prepared by Reeves[1] requires, would select a group of people with psychological dysfunction but not necessarily greater physical disability.

References:

[1] Reeves WC, Wagner D, Nisenbaum R, Jones JF, Gurbaxani B, Solomon L, Papanicolaou DA, Unger ER, Vernon SD, Heim C. Chronic Fatigue Syndrome – A clinically empirical approach to its definition and study. BMC Medicine 2005, 3:19

[2] Reeves WC, Heim C, Maloney EM, Youngblood LS, Unger ER, Decker MJ, Jones JF, Rye DB. Sleep characteristics of persons with chronic fatigue syndrome and non-fatigued controls: results from a population-based study. BMC Neurology 2006, 6:41

[3] Majer M, Jones JF, Unger ER, Youngblood LS, Decker MJ, Gurbaxani B, Heim C, Reeves WC. Perception versus polysomnographic assessment of sleep in CFS and non-fatigued control subjects: results from a population-based study. BMC Neurology 2007, 7:40

[4] Jones JF, Maloney EM, Boneva RS, Jones AB, Reeves WC. Complementary and alternative medical therapy utilization by people with chronic fatiguing illnesses in the United States. BMC Complementary and Alternative Medicine 2007, 7:12

[5] Reeves WC, Jones JF, Maloney E, Heim C, Hoaglin DC, Boneva RS, Morrissey M, Devlin R.Prevalence of chronic fatigue syndrome in metropolitan, urban, and rural Georgia. Popul Health Metr. 2007 Jun 8;5:5.

[6] 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 Int Med 1994, 121:953-959.

[7] Teitelbaum JE, Johnson C, St Cyr J. The use of D-ribose in chronic fatigue syndrome and fibromyalgia: a pilot study. J Altern Complement Med. 2006 Nov;12(9):857-62.

[8] Glass JM. Cognitive dysfunction in fibromyalgia and chronic fatigue syndrome: new trends and future directions. Curr Rheumatol Rep. 2006 Dec;8(6):425-9.

[9] Zachrisson O, Regland B, Jahreskog M, Jonsson M, Kron M, Gottfries CG. Treatment with staphylococcus toxoid in fibromyalgia/chronic fatigue syndrome--a randomised controlled trial. Eur J Pain. 2002;6(6):455-66.

[10] Zachrisson O, Regland B, Jahreskog M, Kron M, Gottfries CG. A rating scale for fibromyalgia and chronic fatigue syndrome (the FibroFatigue scale). J Psychosom Res. 2002 Jun;52(6):501-9.

[11] Oswald J, Salemi S, Michel BA, Sprott H. Use of the Short-Form-36 Health Survey to detect a subgroup of fibromyalgia patients with psychological dysfunction. Clin Rheumatol. 2008 Apr 1

On 2014 Feb 05, Tom Kindlon commented:

A CFS study which raises questions about the use of the Role Emotional (RE) subscale of the SF-36 to define CFS

(This was originally posted here: http://www.biomedcentral.com/1472-6963/3/25/comments but the formatting has been lost and some people may read the paper on PubMed Central)

As I mentioned in the previous comment, this paper recommends, amongst other questionnaires, the use of the SF-36 questionnaire but does not specify which subscales should be used.

One group of researchers[1] have decided to use the physical function, role physical, social function and role emotional subscales of the SF-36 to define disability, with a low score on just one of these subscales being sufficient to satisfy the criteria (i.e. there didn't need to be more than one low scores).

Since then, this definition has gone on to be used in numerous papers (such as [2-5]) as the CDC are using it as the definition they're using for their CFS studies in the US, and they probably have the largest CFS research program in the world. It was used to give the prevalence rate of 2.54% for CFS in the adult population[6]. Most recently, it was used to investigate the prevalence of the reporting of childhoold trauma in this cohort[7].

A study by Fulcher and White (2000)[8] raises questions about the use of the Role Emotional (RE) subscale of the SF-36 to select patients with CFS. The study involved 66 patients with CFS without a current psychiatric disorder, 30 healthy but sedentary controls, and 15 patients with a current major depressive disorder.

It found, amongst other things, that "the two patient groups were significantly more incapacitated than the sedentary controls on all SF-36 measures (p<0.001), except that the patients with CFS were not significantly different in emotional or mental function." Also, "the depressed subjects were significantly more incapacitated in emotional and mental functioning than the patients with CFS p<0.001)."

These results suggest that low scores on the emotional and mental functioning subscales of the SF-36 do not seem to be an intrinsic part of CFS (if they're found, they could be related to comorbid psychiatric issues). They also points out the risks of using the RE subscale alone [especially given CFS shares some characteristics with depression and so some people with depression (but not CFS) could potentially score the required 25 points on the Symptom Inventory] i.e. one could inadvertently include some people who have depression but not CFS, as CFS patients.

References

[1] Reeves WC, Wagner D, Nisenbaum R, Jones JF, Gurbaxani B, Solomon L, Papanicolaou DA, Unger ER, Vernon SD, Heim C. Chronic Fatigue Syndrome – A clinically empirical approach to its definition and study. BMC Medicine 2005, 3:19<br><br>

[2] Raison CL, Lin JM, Reeves WC. Association of peripheral inflammatory markers with chronic fatigue in a population-based sample. Brain Behav Immun. 2008 Dec 11.

[3] Welberg LA, Capuron L, Miller AH, Pagnoni G, Reeves WC. Neuropsychological performance in persons with chronic fatigue syndrome: results from a population-based study.Majer M, Psychosom Med. 2008 Sep;70(7):829-36.

[4] Nater UM, Youngblood LS, Jones JF, Unger ER, Miller AH, Reeves WC, Heim C. Alterations in diurnal salivary cortisol rhythm in a population-based sample of cases with chronic fatigue syndrome. Psychosom Med. 2008 Apr;70(3):298-305.

[5] Nater UM, Maloney E, Boneva RS, Gurbaxani BM, Lin JM, Jones JF, Reeves WC, Heim C. Attenuated morning salivary cortisol concentrations in a population-based study of persons with chronic fatigue syndrome and well controls. J Clin Endocrinol Metab. 2008 Mar;93(3):703-9.

[6] Reeves WC, Jones JF, Maloney E, Heim C, Hoaglin DC, Boneva RS, Morrissey M, Devlin R. Prevalence of chronic fatigue syndrome in metropolitan, urban, and rural Georgia. Popul Health Metr. 2007 Jun 8;5:5.

[7] Heim C, Nater UM, Maloney E, Boneva R, Jones JF, Reeves WC. Childhood trauma and risk for chronic fatigue syndrome: association with neuroendocrine dysfunction. Arch Gen Psychiatry. 2009 Jan;66(1):72-80.

[8] Fulcher KY, White PD. Strength and physiological response to exercise in patients with chronic fatigue syndrome. J Neurol Neurosurg Psychiatry. 2000 Sep;69(3):302-7.