TECH-VER: A Verification Checklist to Reduce Errors in Models and Improve Their Credibility

Background In health economic literature, checklists or best practice recommendations on model validation/credibility always declare verifcation of the programmed model as a fundamental step, such as ‘is the model implemented correctly and does the implementation accurately represent the conceptual model?’ However, to date, little operational guidance for the model verifcation process has been given. In this study, we aimed to create an operational checklist for model users or reviewers to verify the technical implementation of health economic decision analytical models and document their verifcation eforts. Methods Literature on model validation, verifcation, programming errors and credibility was reviewed systematically from scientifc databases. An initial beta version of the checklist was developed based on the checklists/tests identifed from the literature and from authors’ previous modeling/appraisa

Clinical and economic impact of non-adherence in COPD:A systematic review

BACKGROUND: Medication for Chronic Obstructive Pulmonary Disease (COPD) has shown to substantially reduce symptoms and slow progression of disease. However, non-adherence to medication is common and associated with worsened clinical and economic outcomes. OBJECTIVE: The objective of this study was to perform a systematic review of published literature to assess the impact of non-adherence to COPD medication on clinical and economic outcomes. METHODS: A search in PubMed and Web of Science databases was conducted of original studies published from database inception to 2012. Studies must report on the association between adherence to COPD medication and outcomes, published in English in peer-reviewed journals and full texts needed to be available. RESULTS: Twelve full articles were included in the review. Most studies were retrospective database studies. Seven studies reported on the association between adherence and clinical outcomes, two on mortality, three on costs, four on quality of life and one on work productivity. Results indicated a clear association between adherence and both clinical and economic outcomes. Evidence from studies revealed increased hospitalizations, mortality, quality of life and loss of productivity among non-adherent patients. CONCLUSION: This review revealed a clear association between non-adherence to COPD medication and worsened clinical and economic outcomes making non-adherent patients a priority for cost-effective interventions.</p

Stratification of COPD patients towards personalized medicine:reproduction and formation of clusters

BACKGROUND: The global initiative for chronic obstructive lung disease (GOLD) 2020 emphasizes that there is only a weak correlation between FEV(1), symptoms and impairment of the health status of patients with chronic obstructive pulmonary disease (COPD). Various studies aimed to identify COPD phenotypes by cluster analyses, but behavioral aspects besides smoking were rarely included. METHODS: The aims of the study were to investigate whether (i) clustering analyses are in line with the classification into GOLD ABCD groups; (ii) clustering according to Burgel et al. (Eur Respir J. 36(3):531–9, 2010) can be reproduced in a real-world COPD cohort; and (iii) addition of new behavioral variables alters the clustering outcome. Principal component and hierarchical cluster analyses were applied to real-world clinical data of COPD patients newly referred to secondary care (n = 155). We investigated if the obtained clusters paralleled GOLD ABCD subgroups and determined the impact of adding several variables, including quality of life (QOL), fatigue, satisfaction relationship, air trapping, steps per day and activities of daily living, on clustering. RESULTS: Using the appropriate corresponding variables, we identified clusters that largely reflected the GOLD ABCD groups, but we could not reproduce Burgel’s clinical phenotypes. Adding six new variables resulted in the formation of four new clusters that mainly differed from each other in the following parameters: number of steps per day, activities of daily living and QOL. CONCLUSIONS: We could not reproduce previously identified clinical COPD phenotypes in an independent population of COPD patients. Our findings therefore indicate that COPD phenotypes based on cluster analysis may not be a suitable basis for treatment strategies for individual patients. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12931-022-02256-7

Systematic Review and Quality Appraisal of Cost-Effectiveness Analyses of Pharmacologic Maintenance Treatment for Chronic Obstructive Pulmonary Disease:Methodological Considerations and Recommendations

Worldwide, chronic obstructive pulmonary disease (COPD) is a highly prevalent chronic lung disease with considerable clinical and socioeconomic impact. Pharmacologic maintenance drugs (such as bronchodilators and inhaled corticosteroids) play an important role in the treatment of COPD. The cost effectiveness of these treatments has been frequently assessed, but studies to date have largely neglected the impact of treatment sequence and the exact stage of disease in which the drugs are used in real life. We aimed to systematically review recently published articles that reported the cost effectiveness of COPD maintenance treatments, with a focus on key findings, quality and methodological issues. We performed a systematic literature search in Embase, PubMed, the UK NHS Economic Evaluation Database (NHS-EED) and EURONHEED (European Network of Health Economics Evaluation Databases) and included all relevant articles published between 2011 and 2015 in either Dutch, English or German. Main study characteristics, methods and outcomes were extracted and critically assessed. The Quality of Health Economic Studies (QHES) instrument was used as basis for quality assessment, but additional items were also addressed. The search identified 18 recent pharmacoeconomic analyses of COPD maintenance treatments. Papers reported the cost effectiveness of long-acting muscarinic antagonist (LAMA) monotherapy (n = 6), phosphodiesterase (PDE)-4 inhibitors (n = 4), long-acting beta agonist/inhaled corticosteroid (LABA/ICS) combinations (n = 4), LABA monotherapy (n = 2) and LABA/LAMA combinations (n = 2). All but two studies were funded by the manufacturer, and all studies indicated favourable cost effectiveness; however, the number of quality-adjusted life-years (QALYs) gained was small. Less than half of the studies reported a COPD-specific outcome in addition to a generic outcome (mostly QALYs). Exacerbation and mortality rates were found to be the main drivers of cost effectiveness. According to the QHES, the quality of the studies was generally sufficient, but additional assessment revealed that most studies poorly represented the cost effectiveness of real-life medication use. The majority of studies showed that pharmacologic COPD maintenance treatment is cost effective, but most studies poorly reflected real-life drug use. Consistent and COPD-specific methodology is recommended

Measuring burden of disease in both asthma and COPD by merging the ACQ and CCQ:less is more?

Symptoms of asthma and COPD often overlap, and both diseases can co-exist in one patient. The asthma control questionnaire (ACQ) and clinical COPD questionnaire (CCQ) were developed to assess disease burden in respectively asthma or COPD. This study explores the possibility of creating a new questionnaire to assess disease burden in all obstructive lung diseases by integrating and reducing questions of the ACQ and CCQ. Data of patients with asthma, COPD and asthma-COPD overlap (ACO) were collected from a primary and secondary care center. Patients completed ACQ and CCQ on the same day. Linear regression tested correlations. Principal Component Analysis (PCA) was used for item reduction. The secondary cohort with asthma and COPD patients was used for initial question selection (development cohort). These results were reproduced in the primary care cohort and secondary cohort of patients with ACO. The development cohort comprised 252 patients with asthma and 96 with COPD. Correlation between ACQ and CCQ in asthma was R = 0.82, and in COPD R = 0.83. PCA determined a selection of 9 questions. Reproduction in primary care data (asthma n = 1110, COPD n = 1041, ACO = 355) and secondary care data of ACO patients (n = 53) resulted in similar correlations and PCA-derived selection of questions. In conclusion, PCA determined a selection of nine questions of the ACQ and CCQ: working title ‘the Obstructive Lung Disease Questionnaire’. These results suggest that this pragmatic set of questions might be sufficient to assess disease burden in obstructive lung disease in both primary as secondary care.</p

Smoking and health-related quality of life in English general population: Implications for economic evaluations

Copyright @ 2012 Vogl et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.This article has been made available through the Brunel Open Access Publishing Fund.Background: Little is known as to how health-related quality of life (HRQoL) when measured by generic instruments such as EQ-5D differ across smokers, ex-smokers and never-smokers in the general population; whether the overall pattern of this difference remain consistent in each domain of HRQoL; and what implications this variation, if any, would have for economic evaluations of tobacco control interventions. Methods: Using the 2006 round of Health Survey for England data (n = 13,241), this paper aims to examine the impact of smoking status on health-related quality of life in English population. Depending upon the nature of the EQ-5D data (i.e. tariff or domains), linear or logistic regression models were fitted to control for biology, clinical conditions, socio-economic background and lifestyle factors that an individual may have regardless of their smoking status. Age- and gender-specific predicted values according to smoking status are offered as the potential 'utility' values to be used in future economic evaluation models. Results: The observed difference of 0.1100 in EQ-5D scores between never-smokers (0.8839) and heavy-smokers (0.7739) reduced to 0.0516 after adjusting for biological, clinical, lifestyle and socioeconomic conditions. Heavy-smokers, when compared with never-smokers, were significantly more likely to report some/severe problems in all five domains - mobility (67%), self-care (70%), usual activity (42%), pain/discomfort (46%) and anxiety/depression (86%) -. 'Utility' values by age and gender for each category of smoking are provided to be used in the future economic evaluations. Conclusion: Smoking is significantly and negatively associated with health-related quality of life in English general population and the magnitude of this association is determined by the number of cigarettes smoked. The varying degree of this association, captured through instruments such as EQ-5D, may need to be fed into the design of future economic evaluations where the intervention being evaluated affects (e.g. tobacco control) or is affected (e.g. treatment for lung cancer) by individual's (or patients') smoking status

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

BACKGROUND: Combining 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. METHODS: We 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). RESULTS: We 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). CONCLUSION: Investigators 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