Health and Quality of Life Outcomes

Background: The new Global Obstructive Lung Disease (GOLD) guidelines advice to focus treatment in Chronic Obstructive Pulmonary Disease (COPD) on improvement of functional state, prevention of disease progression and minimization of symptoms. So far no validated questionnaires are available to measure symptom and functional state in daily clinical practice. The aim of this study was to develop and validate the Clinical COPD Questionnaire (CCQ). Methods: Qualitative research with patients and clinicians was performed to generate possible items to evaluate clinical COPD control. Thereafter, an item reduction questionnaire was sent to 77 international experts. Sixty-seven experts responded and the 10 most important items, divided into 3 domains (symptoms, functional and mental state) were included in the CCQ (scale: 0 = best, 6 = worst). Results: Cross-sectional data were collected from 119 subjects (57 COPD, GOLD stage I-III; 18 GOLD stage 0 and 44 (ex)smokers). Cronbach's α was high (0.91). The CCQ scores in patients (GOLD 0-III) were significantly higher than in healthy (ex)smokers. Furthermore, significant correlations were found between the CCQ total score and domains of the SF-36 (ρ = 0.48 to ρ = 0.69) and the SGRQ (ρ = 0.67 to ρ = 0.72). In patients with COPD, the correlation between the CCQ and FEV1%pred was ρ =-0.49. Test-retest reliability was determined in 20 subjects in a 2week interval (Intra Class Coefficient = 0.94). Thirty-six smokers with and without COPD showed significant improvement in the CCQ after 2 months smoking cessation, indicating the responsiveness of the CCQ. Conclusion: The CCQ is a self-administered questionnaire specially developed to measure clinical control in patients with COPD. Data support the validity, reliability and responsiveness of this short and easy to administer questionnaire. Published: 28 April 2003 Health and Quality of Life Outcomes 2003, 1:13 Received: 27 February 2003 Accepted: 28 April 2003 This article is available from: http://www.hqlo. com/content/1/1/13 © 2003 van der Molen et al; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL. Page 1 of 10 (page number not for citation purposes) Health and Quality of Life Outcomes 2003, 1 http://www.hqlo. com/content/1/1/13 Introduction Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality in industrialized and developing countries. The mortality rate for COPD is rising and COPD will probably become the third leading cause of death by the year 2020 [1,2]. A study by Feenstra and coworkers showed that there will be an unavoidable increase in the burden of COPD between now and 2015 that is independent from the success of smoking cessation campaigns [3]. In recent years, a great deal of attention has been paid to developing and validating quality of life questionnaires for patients with COPD in order to identify and treat the problems that are most important to these patients [4–6]. Health-related quality of life questionnaires were developed to help identify and treat the functional problems that are most important to patients with COPD. These questionnaires are now being used extensively in clinical trials [7–9]. Health-related quality of life has been defined as the 'functional effect of an illness and its consequent therapy upon a patient, as perceived by the patient' and therefore these questionnaires tend to focus only on the impairments that are important to patients, and often correlate poorly with the clinical status of the airways (e.g. airway inflammation and obstruction) [10]. More recently, the GOLD guidelines have identified the goals of treatment for patients with COPD. These include the patients' goals of improved exercise tolerance and emotional function (health-related quality of life) and also important clinical goals such as prevention of disease progression and minimization of symptoms [11]. Currently, however, there are no instruments that incorporate both the clinicians' and patients' goals as identified by the GOLD committee. The incentive for the development of a practical health status instrument, the Clinical COPD Questionnaire (CCQ) arose from routine clinical management of COPD in general practice where it was recognized that clinicians require a simple tool that will help them to identify not only the clinical status of the airways but also activity limitation and emotional dysfunction in the patient. It was also thought that such an instrument would encourage clinicians not to focus entirely on the state of the airways and to become more conscious of the patients' functional needs. Although the CCQ has been developed primarily for use in clinical practice, it was recognized that a simple, carefully developed and validated instrument would also be useful in clinical trials and other research studies to evaluate the adequacy of clinical management and to assess the effect of interventions on the overall goals of the GOLD guidelines. The methods used to develop the CCQ were adapted from those used to develop both quality of life questionnaires [12] and clinical status questionnaires. Clinical control of COPD was defined to include "The full range of clinical impairment that patients with COPD may experience as a result of their disease" [13]. The initial specifications for the CCQ identified that the questionnaire should not only contain the symptoms that physicians consider to be the most important for estimating the clinical status of the airways but also the functional impairments that are most important to patients (physical and emotional function). Therefore, both clinicians and patients played an important role in determining the items that should be included in the CCQ. After the development and pretesting of the questionnaire, the psychometric properties of the CCQ were evaluated. This article describes the development and validation of the CCQ. Development of the CCQ Item generation Interviews and focus group discussions with COPD patients were conducted to collect potentially relevant items for the CCQ. The disease severity of patients in the focus groups varied from mild to severe. Two focus group discussions were conducted in The Netherlands and one in the United Kingdom including a total number of 34 patients. Twelve individual interviews were conducted in The Netherlands. Interviews and focus group discussions were transcribed. The transcripts were read by a team that included the authors TM, SS and two independent researchers. Emergent themes were discussed and used to generate items. Results of the Dutch interviews and focus groups were analyzed in Dutch and then translated in English for further development of the CCQ. To ensure that all possible items were included, we also reviewed other COPD questionnaires, identified treatment goals from international guidelines and consulted a number of clinicians involved in the treatment of patients with COPD. A list of sixteen items divided into 3 domains that might be used by clinicians to assess clinical COPD control was generated by the team. Item reduction Subjects and methods Seventy-seven international clinicians and experts in the field of COPD management were asked to participate in the item reduction phase. Each expert or clinician was sent a list of the sixteen items identified in the item generation phase and asked to rank them in order of importance and to score the importance of each item for the assessment of clinical COPD control (1=extremely important, 5=useless). Page 2 of 10 (page number not for citation purposes) Health and Quality of Life Outcomes 2003, 1 http://www.hqlo. com/content/1/1/13 Results Sixty-seven questionnaires were returned (87%). The data of sixty respondents could be used for data analysis. Domains The domains functional state (ranking 1; importance 1) and symptoms (ranking 2; importance 1) were considered the most important domains. However, the experts considered the domain mental state (ranking 3; importance 2) also important to evaluate clinical COPD control. Symptom domain Shortness of breath at rest (ranking 1; importance 1) and during exercise (ranking 2; importance 1) were considered to be the most important items, followed by coughing (ranking 4; importance 2), sputum production (ranking 5; importance 2), nightly shortness of breath (ranking 5; importance 3) and fatigue (ranking 5; importance 3). Wheezing (ranking 6; importance 3) and shortness of breath due to emotional distress (ranking 8; importance 4) were ranked as least important items by the clinical experts. Mental state Fear of the next exacerbation (ranking 2; importance 2), depression (ranking 2; importance 2) and fear (in general) (ranking 2; importance 2) were considered as the most important items, followed by bad mood (ranking 4; importance 3) and cognition (ranking 4; importance 3). Functional state In the item reduction questionnaire a subdivision in three standardized activities was proposed. Ninety percent of the respondents indicated that the activities covered important issues of daily life for patients. Nearly 40% of the respondents had remarks regarding the classification and the description of the subdivision. It was often mentioned that social activities do not fit in the row of strenuous and moderate activities. Respondents suggested to add a category of light activities or daily activities. Another remark concerned the usefulness of the activity hobbies. It was suggested not to include hobbies in the functional state domain because the amount of activity can differ between different hobbies. Clinical COPD Questionnaire The symptom domain and the functional state domain were considered extremely important by the experts and were nearly equally ranked. The mental state domain was ranked third and w