Chronic Respiratory Questionnaire Scores Research Articles

Combining scores from different patient reported outcome measures in meta-analyses: when is it justified?

BackgroundCombining outcomes and the use of standardized effect measures such as effect size and standardized response mean across instruments allows more comprehensive meta-analyses and should avoid selection bias. However, such analysis ideally requires that the instruments correlate strongly and that the underlying assumption of similar responsiveness is fulfilled. The aim of the study was to assess the correlation between two widely used health-related quality of life instruments for patients with chronic obstructive pulmonary disease and to compare the instruments' responsiveness on a study level.MethodsWe systematically identified all longitudinal studies that used both the Chronic Respiratory Questionnaire (CRQ) and the St. George's Respiratory Questionnaire (SGRQ) through electronic searches of MEDLINE, EMBASE, CENTRAL and PubMed. We assessed the correlation between CRQ (scale 1 – 7) and SGRQ (scale 1 – 100) change scores and compared responsiveness of the two instruments by comparing standardized response means (change scores divided by their standard deviation).ResultsWe identified 15 studies with 23 patient groups. CRQ change scores ranged from -0.19 to 1.87 (median 0.35, IQR 0.14–0.68) and from -16.00 to 3.00 (median -3.00, IQR -4.73–0.25) for SGRQ change scores. The correlation between CRQ and SGRQ change scores was 0.88. Standardized response means of the CRQ (median 0.51, IQR 0.19–0.98) were significantly higher (p < 0.001) than for the SGRQ (median 0.26, IQR -0.03–0.40).ConclusionInvestigators should be cautious about pooling the results from different instruments in meta-analysis even if they appear to measure similar constructs. Despite high correlation in changes scores, responsiveness of instruments may differ substantially and could lead to important between-study heterogeneity and biased meta-analyses.

Chronic Respiratory Questionnaire as a Predictor of Exercise Participation in Individuals with COPD

The Chronic Respiratory Questionnaire (CRQ) is a well-established and a widely used measure of health-related quality of life (HRQL) for individuals with pulmonary diseases including Chronic Obstructive Pulmonary Disease (COPD). Although regular exercise participation has been shown to improve CRQ scores in COPD patients, relatively little is known about the relationship between CRQ scores and exercise related behavior including outcomes such as attendance and volume of exercise. PURPOSE: To examine the relationship of CRQ scores to both attendance at scheduled center-based visits (exercise adherence) and to the average distances walked (volume of exercise) during training in individuals with COPD while statistically controlling for age, number of comorbidities, and pulmonary function. METHODS: Seventy-four participants (age = 67.0 ± 9.9 years; height = 1.72 ±0.09m; weight = 83.4 ± 22.5 kg) with COPD completed the CRQ (mean total score = 13.9 ± 3.4) and a pulmonary function test to determine their forced expiratory volume in one second (FEV1) as a percentage of predicted values (52.8 ± 18.8%). Participants then started an exercise program where they were expected to complete a total of 36 exercise sessions over a 3-month period with walking as the primary aerobic activity. Participants were asked to record the distance they walked during each exercise session. RESULTS: Regression analyses and partial correlations were performed while controlling for age, number of comorbidities, and FEV1. Total CRQ scores were found to be positively correlated, r = 0.261, p = 0.03 with adherence of the participants to the exercise program. Total CRQ scores were also found to be positively correlated, r = 0.442, p <0.01 with the volume of exercise performed by the participants during the exercise sessions. CONCLUSION: Total score of the CRQ significantly and independently predicts exercise adherence and the volume of exercise performed by individuals with COPD in a 3-month training program. Individuals with higher CRQ scores were more adherent to exercise training and performed higher volumes of exercise than those with lower scores. These results underscore the role of psychological factors in understanding exercise behavior of individuals with COPD. Supported by NIH Grants HL 53755 and AG 10484

Employment status and quality of life in patients with chronic obstructive pulmonary disease

Recently, the conditions for disability benefits were redefined in several countries, stimulating employees to participate on the labour market as long as reasonably possible. Little is known of labour participation and quality of life (QoL) of employees with chronic diseases. This study examines the associations between employment status and QoL in COPD patients. Additionally, the role of lung function, and work-related symptoms and exposures on QoL were explored. Secondary analyses were conducted on baseline data from a randomized control trail. Patients were categorized as: "paid-workers"; "voluntary non-paid workers" (e.g., early retired, house wives) or "disabled for work". QoL was assessed by the Chronic Respiratory Questionnaire (CRQ). Between-group differences in CRQ scores, and associations between work-related symptoms or irritants and CRQ scores were uni- and multivariately analysed. Two hundred and ten patients with COPD were included [mean age 53.9 (SD 6.8) years, FEV(1) %predicted 63.5 (SD 18.5)]. No statistically significant differences in lung function between the employment status subgroups were observed. Multivariable analysis showed that the "disabled" had lower CRQ scores as compared with "paid workers" (0.52 point difference, p<0.001). The CRQ scores of "voluntary non-paid workers" were not significantly different from "paid workers". Within the group paid workers, patients with many work-related clinical symptoms and being susceptible to various work-related irritants experienced a lower QoL than patients who had respectively no symptoms, or who were not susceptible to these factors. Patients with COPD who were disabled for work showed equal severity of airflow limitation but worse QoL, as compared with paid workers.

A Canadian, Multicentre, Randomized Clinical Trial of Home‐Based Pulmonary Rehabilitation in Copd: Rationale and Methods

Pulmonary rehabilitation remains largely underused. Self-monitored, home-based rehabilitation is a promising approach to improving the availability of pulmonary rehabilitation. To report the rationale and methods of a trial comparing the effectiveness of self-monitored, home-based rehabilitation with hospital-based, outpatient rehabilitation in patients with chronic obstructive pulmonary disease (COPD). A parallel-group, randomized, noninferiority, multicentre trial will be performed with 240 patients with moderate to severe COPD. Patients will be randomly assigned to conventional, supervised, hospital-based outpatient rehabilitation or self-monitored, home-based rehabilitation. Both interventions will include a standardized, comprehensive self-management program, in addition to the hospital-based outpatient or home-based exercise program. After the three-month intervention, patients in both groups will be encouraged to continue exercising at home. Patients will be assessed monthly with telephone interviews and in person at enrollment, three months and 12 months. The dyspnea domain of the Chronic Respiratory Questionnaire (CRQ) at 12 months is the primary outcome variable. Secondary outcome variables include total and domain-specific CRQ scores; exercise tolerance and activity of daily living; health service use over the one-year study period; and direct and indirect costs of COPD treatment. An intent-to-treat approach will be used as the primary analysis. The primary analysis will focus on the change in the CRQ dyspnea score using a two-sided t distribution based on 95% CIs. The same approach will be used for secondary continuous outcome variables. The present trial will address two unresolved issues in pulmonary rehabilitation for patients with COPD: the short-term and long-term effectiveness of home-based pulmonary rehabilitation strategies. The authors will also determine if home-based pulmonary rehabilitation can reduce health service use (eg, hospitalizations and emergency visits) and if it can be done at a lower cost than the traditional hospital-based outpatient pulmonary rehabilitation.

Randomized trial of paroxetine in end-stage COPD

Although the underlying pathology is initially confined to the lungs, the associated emotional responses to chronic obstructive pulmonary disease (COPD) contribute greatly to the resulting morbidity. The objective of this study was to examine the effect of an antidepressant drug on disease-specific quality of life in patients with end-stage COPD who present significant depressive symptoms. We conducted a 12-week, randomized double-blind placebo-controlled trial of Paroxetine in which quality of life measured by the Chronic Respiratory Questionnaire (CRQ), an evaluative COPD-specific quality-of-life questionnaire, was the primary outcome. 23 patients were randomized and 15 completed the trial (8 on Paroxetine; 7 on placebo). In the per-protocol analysis, we observed statistically and clinically significant improvements favoring the active treatment in 2 of the 4 domains of the CRQ: emotional function (adjusted mean difference: 1.1; 95% confidence interval [CI]: 0.0 - 2.2) and mastery (difference: 1.1; CI: 0.4 - 1.8). Dyspnea and fatigue improved, but to an extent that did not reach statistical significance. In the intention-to-treat analysis, none of the differences in CRQ scores was significant. Paroxetine was not associated to any worsening of respiratory symptoms. The results of this small randomized trial indicated that patients with end-stage COPD may benefit from antidepressant drug therapy when significant depressive symptoms are present. This study underlined the difficulties in conducting experimental studies in frail and elderly patients with COPD.

Evaluation of the minimal important difference for the feeling thermometer and the St. George's Respiratory Questionnaire in patients with chronic airflow obstruction

Background and objective The chronic respiratory questionnaire (CRQ), the St. Georges Respiratory Questionnaire (SGRQ), and the feeling thermometer (FT) evaluate change in health-related quality of life (HRQL) in patients with chronic airflow limitation (CAL). Although the interpretability, and in particular the minimal important difference (MID) in score changes, is well established for the CRQ, this is not the case for the SGRQ and FT. The objective of our study is to explore the interpretation of the SGRQ and FT. Methods We analyzed data from 84 patients who completed the CRQ, SGRQ, and FT before beginning pulmonary rehabilitation and 3 months later. We calculated correlations between the four CRQ domains (dyspnea, fatigue, emotional function, and mastery) and the three SGRQ domains (symptoms, activities, and impact), the SGRQ total score, and the FT. When Pearson's correlations were ⩾0.5, we constructed regression equations and used the slope to calculate the change in SGRQ and FT score that corresponded to a change in CRQ score of 0.5 (the MID). Having established MID for SGRQ we than used a similar approach to examine the relation between the SGRQ and FT results. Results Comparison with the CRQ dyspnea domain suggested the MID in SGRQ total score is approximately 3.05 with a 95% confidence interval (95% CI) ranging from 0.39 to 5.71 and a change of 5.67 (95% CI 3.43–7.92) represents a moderate change (1.0 on the CRQ dyspnea domain). The MID for the FT based on the CRQ fatigue domain was 6.1 (95% CI 1.87–10.28). The FT MID based on the SGRQ activities domain, impacts domain, and total score were, respectively, 7.4 (95% CI 3.44–11.35), 5.6 (95% CI 1.6–9.64), and 5.9 (95% CI 1.97–9.78). Conclusion An MID for the SGRQ approximates the previously suggested estimate of 4 on a scale of 0 to 100. The MID for the FT in patients with CAL is approximately 5 to 8 units on the 0 to 100 scale. These MID estimates should facilitate interpretation of clinical trials in which outcome measures include the SGRQ or FT.

Occupational status and bronchoprovocative factors in relation to health-related quality of life in patients with COPD. A cross-sectional study in general practice

Objective:To investigate (1) associations between occupational status, work-related airway symptoms and quality-of-life and (2) the relationship between quality-of-life and bronchial symptoms due to common provocative exposure (e.g., domestic dust exposure, smog) in patients with chronic obstructive pulmonary disease (COPD) in general practice.Design:Secondary analyses on baseline data from the COOPT study, a randomised controlled trial investigating the effectiveness of fluticasone and N-acetylcysteine in COPD. Patients were subdivided into four groups according to their occupational status: ‘paid employment’; ‘no paid employment’; ‘incapacitated for work’; and ‘retired’. Quality-of-life was assessed by Chronic Respiratory Questionnaire (CRQ). This questionnaire measures four domains of health status, i.e. ‘activity’, ‘emotions’, ‘fatigue’, and ‘mastery’. Susceptibility to exposure to common bronchoprovocative factors was assessed with an ad hoc questionnaire. Between-group differences in CRQ scores and associations between CRQ scores and work-related airway symptoms were analysed using univariate and multivariate techniques. Results: 320 COPD patients were included (mean age 59.4 [SD 9.6] years, FEV1 %predicted 60.5 [SD 18.8]). Univariate analysis revealed differences in FEV1 %predicted between occupational status subgroups (p<0.001): paid work 65.3% (SD 16.7), no paid work 58.5% (18.7), incapacitated for work 64.1% (SD 20.5) and retired 54.8% (SD 18.1). Multivariate analysis showed that patients incapacitated for work had statistically significant lower CRQ total, activity, fatigue and mastery domain scores compared with patients in paid employment. In those employed (n=93), severity of work-related airway symptoms correlated with the CRQ total score (r=−0.48, p<0.001). Univariately, patients susceptible to many common bronchoprovocative factors had a lower total CRQ score (r=−0.42, p<0.001).Conclusion:In patients with COPD, quality-of-life may depend on susceptibility to common bronchoprovocative factors. COPD patients who are incapacitated for work show equal severity of airflow limitation, but worse quality-of-life compared with patients in paid employment.

Pulmonary rehabilitation for chronic obstructive pulmonary disease.

The widespread application pulmonary rehabilitation in chronic obstructive pulmonary disease (COPD) should be preceded by demonstrable improvements in function attributable to the programs. This review updates that reported by Lacasse et al Lancet 1996; 748:1115-1119. To determine the impact of rehabilitation on health-related quality of life (QoL) and exercise capacity in patients with COPD. The 14 randomized controlled trials (RCTs) included in the original meta-analysis were included. Additional RCTs were identified from the Cochrane Airways Group's registry of COPD RCTs using the strategy: [exp, lung diseases, obstructive] and [exp, rehabilitation or exp, exercise therapy] and [research design or longitudinal studies or evaluation study or randomized controlled trial]. Abstracts presented at American Thoracic Society 1980-2000, American College of Chest Physicians 1980-2000 and European Respiratory Society 1987-2000 were also searched. RCTs of rehabilitation in patients with COPD in which quality of life (QoL) and/or functional (FEC) or maximal (MEC) exercise capacity were measured. Rehabilitation was defined as exercise training for at least 4 weeks with or without education and/or psychological support. Control groups received conventional community care without rehabilitation. Weighted mean differences (WMD) were calculated using a random-effects model. Missing data from the primary study reports were requested from the authors. 23 RCTs met the inclusion criteria. Statistically significant improvements were found for all the outcomes. In three important domains of QoL (Chronic Respiratory Questionnaire scores for Dyspnea, Fatigue and Mastery), the effect was larger than the minimal clinically important difference of 0.5 units using this instrument. For example Dyspnoea score: WMD 0.98 units, 95% Confidence Interval (95% CI) 0.74 - 1.22 units; n=9 trials. For FEC and MEC, the effect was small and a little below the threshold of clinical significance for the 6- minute walking distance: WMD 49 m, 95% CI: 26 - 72 m; n=10 trials. Rehabilitation relieves dyspnea and fatigue and enhances patients' sense of control over their condition. These improvements are moderately large and clinically significant. The average improvement in exercise capacity was modest. Rehabilitation forms an important component of the management of COPD.

A randomised controlled trial of four weeks versus seven weeks of pulmonary rehabilitation in chronic obstructive pulmonary disease

BACKGROUNDPulmonary rehabilitation programmes have been shown to improve both exercise tolerance and health status in patients with chronic obstructive pulmonary disease (COPD). The optimal duration for a pulmonary rehabilitation programme...

Usefulness of the Medical Research Council (MRC) dyspnoea scale as a measure of disability in patients with chronic obstructive pulmonary disease

BACKGROUNDMethods of classifying chronic obstructive pulmonary disease (COPD) depend largely upon spirometric measurements but disability is only weakly related to measurements of lung function. With the increased use of pulmonary...

A Systematic Overview of the Measurement Properties of the Chronic Respiratory Questionnaire

BACKGROUND: Assessment of health‐related quality of life (HRQL) of patients with chronic lung disease has become an important aspect of many clinical investigations. The authors examined the measurement properties of a disease‐specific HRQL questionnaire, the Chronic Respiratory Questionnaire (CRQ), when used by independent investigators in clinical trials and observational studies.METHODS: All published papers citing the original 1987 CRQ publication were identified using the Science Citation Index, and abstracts presented at international conferences were found by hand search. Clinical trials and observational studies were included if they reported data bearing on the CRQ’s measurement properties.RESULTS: Of 90 papers and 20 abstracts, 32 met the inclusion criterion. CRQ domains of fatigue, mastery and emotional function have high reliability, and face, content and construct validity in differentiating among patients with better and worse HRQL. Because of its self‐generated items, the dyspnea domain works less well in discriminating among patients with lesser and greater dyspnea. When CRQ has been used to evaluate treatment, all four domains have performed well in detecting small treatment effects. The minimal important difference in CRQ score (0.5 per item) provides guidance for both planning studies and interpreting results. To maximize CRQ interpretability, investigators should present results as the mean score per item within each domain on a seven‐point scale.CONCLUSION: The CRQ has proved valid and responsive to change. Its standardization and continued wide use will enhance the understanding of the impact of treatments on patients’ HRQL.