Health and Quality of Life Outcomes - Latest Comments

Differences in medication usage in the Wichita and Georgia cohorts could be due to the different methods of operationalizing the Fukuda criteria that were used

Tom Kindlon — 2009-12-04T12:30:18Z

Medication usage was not the same in the CFS populations found in the Wichita and Georgia populations.

The authors summarise the similarities and differences in the following paragraph:

“Our findings confirm those from a previous study of medication use in persons with CFS from Wichita, Kansas. Both studies found significantly higher usage of pain relievers, gastrointestinal drugs, antidepressants and benzodiazepines by persons with CFS compared to Well controls. Unlike the Wichita study, though, persons with CFS in Georgia were not significantly more likely than controls to use hormones and supplements but were significantly more likely than controls to use muscle relaxants and anti-allergy and cold/sinus medications. Overall, compared to persons with CFS from the Wichita study7, a smaller proportion of persons with CFS in Georgia used pain-relievers (65.5% in Georgia vs. 87.8% in Wichita), supplements/vitamins (44.3% vs. 62.2%), antidepressants (36.3% vs. 41.1%), antibiotics (7.1% vs. 16.7%), hormones (43.4% vs. 52.5%. among women only, 11.8% among all CFS), antihypertensive drugs (17.7% vs. 21.1%), muscle relaxants (8.9% vs. 12.2%), anti-asthma medications (7.1% vs. 12.2%), glucose-lowering drugs (0.9% vs. 4.4%.). Use of other prescription drug categories such as lipid-lowering drugs (11.5% vs.12.2%) and benzodiazepines (12.4%, vs. 11.1% respectively) was similar in Georgia and Wichita (Kansas). The relatively lower usage of most prescription drug medications by persons with CFS in Georgia compared to Wichita may reflect lower seeking of, or lower access to, health care.”

An alternative reason could be that the two sets of criteria for CFS used were not selecting the same type of patients.

The current study[1] uses the empiric definition for CFS[2]. As one can see from the paper that gives the criteria involved in the empiric definition, although it is also based on the Fukuda definition[3], a different number of patients satisfy the criteria [2] compared to how the authors used the definition in the initial study of the Wichita population.

This change looks more significant when one looks at the prevalence rates for CFS obtained in the two cohorts. In the Wichita study[4], the prevalence of CFS was 0.235% (95% confidence interval, 0.142%-0.327%). In the Georgia study[5], the prevalence of CFS was 2.54%, 10.8 times the prevalence in the Wichita study!

Concerns have been raised[6,7] about the newer method[2] of operationalizing the Fukuda definition[3] that were used in the current study[1]. In the only study[7] using the empiric criteria [2] that I am aware of that did not involve the CDC CFS team, 38% of those chosen as patients with Major Depressive Disorder but not CFS, were found to satisfy the new criteria[2] for CFS.

References

1] Boneva RS, Lin JM, Maloney EM, Jones JF, Reeves WC. Use of medications by people with chronic fatigue syndrome and healthy persons: a population-based study of fatiguing illness in Georgia. Health Qual Life Outcomes. 2009 Jul 20;7:67.

[2] 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 Med. 2005 Dec 15;3:19.

[3] 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.

[4] Reyes M, Nisenbaum R, Hoaglin DC, Unger ER, Emmons C, Randall B, Stewart JA, Abbey S, Jones JF, Gantz N, Minden S, Reeves WC: Prevalence and incidence of chronic fatigue syndrome in Wichita, Kansas. Arch Int Med 2003, 163:1530-1536.

[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] Jason LA, Richman JA. How science can stigmatize: The case of chronic fatigue syndrome. Journal of Chronic Fatigue Syndrome 2008, 14, 85-103.

[7] Jason LA, Najar N, Porter N, Reh C. Evaluating the Centers for Disease Control’s empirical chronic fatigue syndrome case definition. Journal of Disability Policy Studies 2009, 20, 93-100. doi:10.1177/1044207308325995

Individual validity of patient reported outcomes: The use of the Clinical COPD Questionnaire (CCQ) in primary care

Jan Willem Herman Kocks — 2009-12-04T12:29:44Z

Individual validity of patient reported outcomes: The use of the Clinical COPD Questionnaire (CCQ) in primary care

JWH Kocks, T. van der Molen

Department of General practice, University Medical Center Groningen, Groningen, The Netherlands

JWH Kocks – j.w.h.kocks@med.umcg.nl – corresponding author
T van der Molen – t.van.der.molen@med.umcg.nl

Abstract
Response to Ställberg et al. Health and Quality of Life Outcomes 2009,7:26

Dear Editor,

With great interest we have read the article by Ställberg and colleagues[1] describing the validation of the Clinical COPD Questionnaire (CCQ) in primary care. As developer (TvM) and researcher (JWHK) of the CCQ we like to thank the authors for performing a study so relevant for clinical practice, but also like to comment on two essential results and interpretations by the authors. The authors use a different approach than commonly to determine the stability of the patient reported outcomes (test-retest reliability). Based on statistical analyses alone the authors conclude that the CCQ reliability might not be sufficient for individual patient monitoring.

The test-retest reliability is assesed using the St. George’s respiratory questionnaire (SGRQ) as indication for stability. The authors state in the discussion that they choose a long time- interval of: ??? to determine the test-retest reliability. A long time-interval indeed minimizes the problem of recall bias[2], but adds difficulty determining the stability using the intra class coefficient. The authors choose an other widely used health status questionnaire to determine change. The use of the SGRQ as method to determine stability raises two issues: 1. the cut off point of 4 points as the minimal clinically important difference is mainly based on the effectiveness of medication in a one year trial, which may not be sufficient bases to use it as a stability measure[3] and 2. The timeframe on which SGRQ “stability” was determined is “lately” as the authors describe in their methods. We suggest for future studies the use of the commonly used Global Rating of Change scale (GRC) in a shorter timeframe.

The authors state that the CCQ’s reliability may not be sufficient for the monitoring of individual patients. The result of the crohbach’s alpha (0.85) and the intra class coefficient (0.85) found in the study are indeed below the suggested threshold of 0.9 for individual monitoring. In previous studies the crohnbach’s alpha and the ICC’s of the CCQ were higher 0.89 to 0.99[4,5]. In the previous paragraph we already discussed the validity of the method to determine the ICC. Taken this into account to our opinion the authors can therefore not justify the conclusion on the individual patient monitoring in this specific study. Next to the statistical grounds, we previously proposed a new method to determine the individual validity of patient reported outcomes[6]. In short, we suggest to determine the concordance between the patient score and an in-depth interview with the patient. We performed a study using this method for the CCQ and the concordance (Lin’s concordance correlation confident (CCC)) in 44 patients was 0.88 (submitted). These results together with the feasibility to use in routine practice, we suggest the CCQ can be used in monitoring individual patients next to clinical trials and quality of care monitoring.

Authors contributions
JWHK and TvdM have written this letter together.

Reference List

1. Stallberg B, Nokela M, Ehrs PO, Hjemdal P, Jonsson EW: Validation of the clinical COPD Questionnaire (CCQ) in primary care. Health Qual Life Outcomes 2009, 7: 26.
2. Stull DE, Leidy NK, Parasuraman B, Chassany O: Optimal recall periods for patient-reported outcomes: challenges and potential solutions. Curr Med Res Opin 2009, 25: 929-942.
3. Schunemann HJ, Griffith L, Jaeschke R, Goldstein R, Stubbing D, Guyatt GH: Evaluation of the minimal important difference for the feeling thermometer and the St. George's Respiratory Questionnaire in patients with chronic airflow obstruction. J Clin Epidemiol 2003, 56: 1170-1176.
4. Damato S, Bonatti C, Frigo V, Pappagallo S, Raccanelli R, Rampoldi C et al.: Validation of the Clinical COPD questionnaire in Italian language. Health Qual Life Outcomes 2005, 3: 9.
5. Molen van der T, Willemse BW, Schokker S, Ten Hacken NH, Postma DS, Juniper EF: Development, validity and responsiveness of the Clinical COPD Questionnaire. Health Qual Life Outcomes 2003, 1: 13.
6. van der Molen T, Kocks JW: Do health-status measures play a role in improving treatment in chronic obstructive pulmonary disease? Expert Opin Pharmacother 2006, 7: 57-61.

Inappropriate criticism

Oliver, Rudolf Herber — 2008-01-22T11:09:58Z

While we welcome any constructive criticism to improve the quality of our systematic review, we were somewhat disappointed to observe that our review has not been read carefully enough. Franks demurs the missing of too many of his studies which unfortunately, however, did not meet our inclusion criteria as stated in the method section. There it says that articles were excluded if they investigated the impact of specific treatments (e.g. bandaging systems) or settings (e.g. leg ulcer clinics) on QoL. The rationale for doing this can be found in the discussion section under the heading “Weaknesses and strengths of this review”.

QOL in Leg ulceration: too many missing studies

Peter Franks — 2007-07-27T14:14:18Z

While I applaud the notion of a systematic review of quality of life in leg ulceration, I was disappointed to observe just one paper from our research team had made it into the review. While systematic reviews are by definition systematic, they are not necessarily as inclusive as they could be. We have been working in this area for a number of years and have published widely. I suggest the authors should look at their search strategy as it is clearly not able to pick ours (and other) key studies. For your reference the folliowing papers have appeared in peer reviewed journals:

Franks PJ, Moffatt CJ, Oldroyd M, Bosanquet N, Connolly M, Greenhalgh RM,

McCollum CN (1994) “Community leg ulcer clinics: Effect on quality of life.”

Phlebology 9 (2): 83-86.

Franks PJ, Bosanquet N, Brown D, Straub J, Harper DR, Ruckley CV (1999)

“Perceived health in a randomised trial of treatment for chronic venous ulceration.”

Eur. J. Vasc. Endovasc. Surg. 17 (2): 155-159.

Franks PJ, Moffatt CJ, Connolly M, Fielden S, Ellison DA, Groarke L, McCollum CN (1999). “Quality of life in venous ulceration: a randomised trial of two bandage systems.” Phlebology 14 (3): 95-99.

Franks PJ, Moffatt CJ (2001)

“Health related quality of life in patients with venous ulceration: use of the Nottingham Health Profile.”

Quality of Life Research 10 (8): 693-700.

Franks PJ, McCullagh L, Moffatt CJ (2003)

“Assessing quality of life in patients with chronic leg ulceration using the Medical Outcomes Short Form-36 questionnaire.”

Ostomy/ Wound Management. 49 (2): 26-37.

Franks PJ, Moody M, Moffatt CJ, Patton J, Bradley L, Chaloner D, Stevens J, Stevens J, Lewis C. (2004). “Quality of life in a trial of short stretch versus four layer bandaging in the management of chronic venous ulceration.”

Phlebology 19 (2): 87-91

Franks PJ, Moffatt CJ, Doherty DC, Smithdale R, Martin R (2006)

“Longer term changes in quality of life in chronic leg ulceration.”

Wound Repair & Regeneration: 14; 536-541

Franks PJ, Moffatt CJ (2006). Do clinical and social factors predict quality of life in leg ulceration? Int J Low Extrem Wounds.: 5 (4). 236-43

Hareendran A, Doll H, Wild DJ, Moffatt CJ, Musgrove E, Wheatley C, Franks PJ (2007). “The Venous Leg Ulcer Quality of Life (VLU-QoL) questionnaire: Development and Psychometric Validation.” Wound Repair & Regeneration. 15(4); 465-473

Theory - but why?

Christian Apfelbacher — 2007-05-29T10:53:12Z

We welcome the article by Pollard et al. which draws attention to the lack of theory underlying subjective health outcome measures and the methodological variation in the development of these measures.

As an example of a theoretical model the authors use the International Classification of Functioning, Disability and Health (ICF). They refer to it as a ‘biomedical model’, when in fact it adopts a biopsychosocial approach.

Pollard and colleagues base their paper on the assumption that a theoretical framework is advantageous, but the authors fail to convincingly convey why. Whilst mentioning that measures developed within a theoretical framework have the advantage of allowing “underlying processes to be investigated” and “interventions appropriately targeted”, they fail to clarify why these advantages occur and how this relates to a theoretical framework.

Undoubtedly, there are different notions of theory prevailing and it is certainly debatable what a theory constitutes, but irrespective of this, the above reservations are pertinent and need addressing.

Christian Apfelbacher

Matthew Hankins

Carrie Llewellyn

Anjum Memon

Helen Smith

Alice Theadom

More details?

Sophie Habets — 2007-05-08T10:36:43Z

Very interresting publication. Are there any additional data available regarding the results of table 3 (Frequency distribution before/after therapy compared with population norm values) for each item individually?

Palliative care for COPD patients

Balamugesh Thangakunam — 2007-05-08T10:36:20Z

The article by Yohannes AM is worth commending (1). The need for sensitizing patients and physicians treating COPD, to consider palliative care services to improve the quality of life has been highlighted well. I would like to make few comments.

While discussing the use of long acting bronchodilators the authors have mentioned that those on tiotropium need close monitoring for adverse effects like urinary infection. We suppose this should read urinary retention, since tiotropium is frequently associated with urinary retention and not urinary infection (2).

In the section on oxygen therapy it is mentioned that the “long term benefits of oxygen therapy for COPD patients remain inconclusive” We would like to question the veracity of this statement. There are two landmark trials that showed improvement in survival with long term oxygen therapy for hypoxic COPD patients (3,4). The Global Initiative for chronic Obstructive Lung Diseases guidelines of 2006 also mention that oxygen therapy improves survival (www.goldcopd.com) There also have a beneficial impact on exercise capacity, lung mechanics, and mental state (5). Even short term use of ambulatory oxygen is associated with significant improvement in health related quality of life in COPD patients who do not fulfill criteria for long term oxygen therapy but demonstrate significant exertional desaturation (6). However caution needs to be exercised in selecting patients for long term oxygen therapy since too much oxygen will lead to carbon-di-oxide retention.

The role of inhaled glucocorticoids has not been discussed. Glucocorticoids have been proven to reduce the rate of decline in quality of life and reduce the frequency of exacerbations in patients with severe COPD (7).

There is no mention on the role of smoking cessation in this article. Smoking cessation is the single most effective and cost effective way to reduce exposure to COPD risk factors. It is recommended that all smokers with COPD should be should be offered the most intensive smoking cessation intervention feasible (www.goldcopd.com). However this may not be appropriate in a terminally ill COPD patient considering the nicotine withdrawal effects.

References

1. Yohannes AM. Palliative care provision for patients with chronic obstructive pulmonary disease. Health Qual Life Outcomes. 2007,5:17.

2. Kesten S, Jara M, Wentworth C, Lanes S. Pooled clinical trial analysis of tiotropium safety. Chest 2006,130:1695-703.

3. Report of the Medical Research Council Working Party. Long-term domiciliary oxygen therapy in chronic hypoxic cor pulmonale complicating chronic bronchitis and emphysema. Lancet 1981; i: 681–6.

4. Nocturnal Oxygen Therapy Trial Group. Continuous or nocturnal oxygen therapy in hypoxaemic chronic obstructive lung disease – a clinical trial. Ann Intern Med 1980; 93: 391–8.

5. Tarpy SP, Celli BR. Long-term oxygen therapy. N Engl J Med 1995,333:710-4.

6. Eaton T, Garrett JE, Young P, Fergusson W, Kolbe J, Rudkin S, Whyte K. Ambulatory oxygen improves quality of life of COPD patients: a randomised controlled study. Eur Respir J 2002,20:306-12.

7. Yang Ia, Fong K, Sim E, Black P, Lasserson T. Inhaled corticosteroids for stable chronic obstructive pulmonary disease. Cochrane Database Syst Rev 2007,18(2):CD002991.

Terminology or context?

Frank Snoek — 2007-02-13T16:11:40Z

In her feedback on FDA's draft guidance on Patient Reported Outcome (PRO) measures, professor Bradley among other issues, underscores the importance of making a distinction between health status and quality of life. She cites her commentary in the Lancet (2001), where she gave the example of the influential United Kingdom Prospective Study (UKPDS). She also cites the editorial with Tamburini in this journal (2003) citing the Lancet commentary, using the UKPDS as an example of misuse of the term 'quality of life'. For those not familiar with diabetes literature, the UKPDS was a large prospective study in type 2 diabetes that found diabetes-related complications but not intensive therapy to have a negative impact on the Quality of Life of Type 2 diabetes patients (1999). According to professor Bradley the UKPDS used health status measures, and quality of life was not measured. She bluntly states that "this is a very different conclusion and a far less desirable one than the one reached erroneously by the UKPDS authors". It is unclear to me how anyone could know what the desired outcomes were for the UKPDS study group, unless the authors had made this public, which to my knowledge they never did. I leave it to the UKPDS authors to reply to professor Bradley's speculation. More importantly, professor Bradley fails to report that in the UKPDS a number of validated patient reported outcomes were used to determine the impact - if any - on the patients life quality, of diabetes complications, hypoglycaemic episodes and intensive therapy per se. Next to the EQ5-D, the Profile of Mood States (POMS), The Cognitive Failures Questionnaire, questions regarding symptoms, and work satisfaction were administered, tapping into different relevant domains of psychological and physical functioning. We can debate whether the participating patients should have been asked the question "How do you rate your quality of life", and how would you rate it if you did not have diabetes/intensive therapy/hypoglycaemic episodes/complications" but I seriously doubt that this would have provided us with additional information. Contrary to what professor Bradley suggests, the findings of the UKPDS in my view have added important knowledge to the field of quality of life research, showing that complications (and not diabetes or intensive treatment per se) reduce subjective well-being in type 2 diabetes, and that those who reported more frequent hypoglaemic episodes also reported more tension, overall mood disturbance and less work satisfaction.

We all struggle with the concept of "quality of life" and we should try to avoid abuse of the term. However, to repeatedly take the UKPDS as a bad example of mixing health status and "quality of life" is not justified and indeed misleading. Such comments are likely to cause more confusion rather than clarity.

To add to the discussion on perceptions of health as opposed to quality of life, it is of note that (self-reported) mood and self-rated health are among the strongest predictors of clinical outcomes and mortality (e.g. see Hennesy et al.,1994; Nicholson et al., 2006). In the context of medical care they seem appropriate and discriminant questions, based on people's perceptions of how well they feel they are doing.

How far off a persons' 'quality of life' can that be?

Incremental or average cost-utility of routine cataract surgery?

Erkki Soini — 2006-10-24T16:44:54Z

I read with interest and enthusiasm the recently published article by Räsänen et al. that studied the cost-utility of routine cataract surgery in real life setting. The presented routine approach with everyday conditions is novel. Furthermore, the article is excellent and a well-written piece of hard work. Consequently, these comments are aimed as advises for future novel research. Unfortunately, the article raised few important methodological issues which should be discussed in details.

Firstly, authors refer that "HRQoL gain was assumed to last till the end of the remaining statistical life" and "this approach is typically used for the calculation of QALYs gained by the medical intervention". I assume that the authors have applied direct extrapolation without any level of uncertainty to calculate the QALYs. Unfortunately, the golden standard for the QALY estimation seems to be Markov state transition models in which e.g. the risk of death can be properly handled.

Secondly, authors do not point out any system (e.g. multivariate analysis) to handle the confounding which is typically present in routine-styled settings. This raises the question of comparability between one eye and two eye surgery even in the average cost per average QALY (i.e. cost-effectiveness ratio, CER) setting. This comparison seems to be present in e.g. figure 10 as the cost-effectiveness acceptability curves (CEAC).

Thirdly, in addition to deterministic approach, authors use stochastic approach and use bootstrapping-based probabilistic sensitivity analysis (PSA) to present the sampling uncertainty as the cost-effectiveness planes (cf. figures 7-9). In their planes, axes are referred as "incremental". Unfortunately, these axes are not incremental as they compare subgroup results to "no treatment" option. Actually, the axes give distributions for average costs and average effectiveness. Thus, the decision is not based on the incremental cost-effectiveness ratio (ICER) and the consequent decision at margin is very different from the decision at average (e.g. CER: whether to operate any eye or not vs. e.g. ICER: whether to operate both eyes or just one eye). This difference in interpretation between CER and ICER as well as the use of generic health-related quality of life (HRQoL) and CER as the primary outcomes raise ethical questions which should have been addressed. For example, in novel cancer medication evaluations, the comparator is typically the best supportive care (BSC) introducing some costs and effectiveness, if no other treatment option is relevant.

Fourthly, authors do not point out whether or not dependence between average costs and average effectiveness was present. This may have an impact on the shapes of CEACs and, thus, to the probabilities of average cost-effectiveness.

Fifthly, the cost per QALY approach handled this way refers to the comparison of allocative efficiency (e.g. league tables). In economics, technical efficiency is a necessary condition for allocative efficiency. Unfortunately, we cannot be sure how technically efficient are the operations in the trial hospital and, thus, how generalizable are the cost per QALY results.

Lastly, I suggest utilizing incremental net monetary benefit (INMB) regression method in depicting the CEACs and handling the subgroup heterogeneity in future routine research. In this case, INMB may have been obtainable through propensity score methods. Authors point out the importance of optimizing the custom in which cataract operations are carried out. This may have been obtainable through multivariate INMB regression methods including e.g. waiting time, type of cataract, visual acuity at baseline, subgroup and propensity score as the independent variables. Thank you.

Health Related Quality of life trajectories and Predictors following CABS

frank Pakravan — 2006-09-12T16:51:41Z

The observations made and the conclusions drawn here in this paper are so relevant to patients that have had a Coronary Artery Bypass Surgery that I would personally like to see more funding into such research. I commend the public to view the findings in light of the parameters of the research and draw relevance into their own lives.