COMPARING POWER AND MULTIPLE SIGNIFICANCE LEVEL FOR STEP UP AND STEP DOWN MULTIPLE TEST PROCEDURES FOR CORRELATED ESTIMATES

We consider hypothesis testing problems arising in e.g. the context of comparing k treatments with a control. The case of equi-correlated estimates is mainly discussed, although also unequal correlated estimates (e.g. unequal sample sizes for the treatments, when compared to a control treatment) are mentioned briefly. So called step down test procedures are compared with step up test procedures, with respect to power functions. Comparisons of rejected null hypotheses are also performed. No practical differences in performances between step up and step down test procedures could be found for finite sample sizes

Evaluation of the Swedish National Stroke Campaign : A population-based time-series study

Background: Time delay from stroke onset to hospital arrival is an important obstacle to recanalization therapy. To increase knowledge about stroke symptoms and potentially reduce delayed hospital arrival, a 27-month national public information campaign was conducted in Sweden. Aim: To assess the effects of a national stroke campaign in Sweden. Methods: This nationwide study included 97,840 patients with acute stroke, admitted to hospital and registered in the Swedish Stroke Register from 1 October 2010 to 31 December 2014 (one year before the campaign started to one year after the campaign ended). End points were (1) proportion of patients arriving at hospital within 3 h of stroke onset and (2) the proportion < 80 years of age receiving recanalization therapy. Results: During the campaign, both the proportion of patients arriving at hospital within 3 h (p < 0.05) and the proportion receiving recanalization therapy (p < 0.001) increased. These proportions remained stable the year after the campaign, and no significant improvements with respect to the two end points were observed during the year preceding the campaign. In a multivariable logistic regression model comparing the last year of the campaign with the year preceding the campaign, the odds ratio of arriving at hospital within 3 h was 1.05 (95% confidence interval (CI): 1.00–1.09) and that of receiving recanalization was 1.34 (95% CI: 1.24–1.46). Conclusion: The Swedish National Stroke Campaign was associated with a sustained increase in the proportion of patients receiving recanalization therapy and a small but significant improvement in the proportion arriving at hospital within 3 h

Quality of life in chronic conditions using patient-reported measures and biomarkers : a DEA analysis in type 1 diabetes

BACKGROUND: A chronic disease impacts a patient's daily life, with the burden of symptoms and managing the condition, and concerns of progression and disease complications. Such aspects are captured by Patient-Reported Outcomes Measures (PROM), assessments of e.g. wellbeing. Patient-Reported Experience Measures (PREM) assess patients' experiences of healthcare and address patient preferences. Biomarkers are useful for monitoring disease activity and treatment effect and determining risks of progression and complications, and they provide information on current and future health. Individuals may differ in which among these aspects they consider important. We aimed to develop a measure of quality of life using biomarkers, PROM and PREM, that would provide an unambiguous ranking of individuals, without presuming any specific set of importance weights. We anticipated it would be useful for studying needs and room for improvement, estimating the effects of interventions and comparing alternatives, and for developing healthcare with a broad focus on the individual. We wished to examine if efficiency analysis could be used for this purpose, in an application to individuals with type 1 diabetes.RESULTS: We used PROM and PREM data linked to registry data on risk factors, in a large sample selected from the National Diabetes Registry in Sweden. Efficiency analysis appears useful for evaluating the situation of individuals with type 1 diabetes. Quality of life was estimated as efficiency, which differed by age. The contribution of different components to quality of life was heterogeneous, and differed by gender, age and duration of diabetes. Observed quality of life shortfall was mainly due to inefficiency, and to some extent due to the level of available inputs.CONCLUSIONS: The efficiency analysis approach can use patient-reported outcomes measures, patient-reported experience measures and comorbidity risk factors to estimate quality of life with a broad focus on the individual, in individuals with type 1 diabetes. The approach enables ranking and comparisons using all these aspects in parallel, and allows each individual to express their own view of which aspects are important to them. The approach can be used for policy regarding interventions on inefficiency as well as healthcare resource allocation, although currently limited to type 1 diabetes

Patient-Reported Outcome Measures and Risk Factors in a Quality Registry: A Basis for More Patient-Centered Diabetes Care in Sweden

Diabetes is one of the chronic diseases that constitute the greatest disease burden in the world. The Swedish National Diabetes Register is an essential part of the diabetes care system. Currently it mainly records clinical outcomes, but here we describe how it has started to collect patient-reported outcome measures, complementing the standard registry data on clinical outcomes as a basis for evaluating diabetes care. Our aims were to develop a questionnaire to measure patient abilities and judgments of their experience of diabetes care, to describe a Swedish diabetes patient sample in terms of their abilities, judgments, and risk factors, and to characterize groups of patients with a need for improvement. Patient abilities and judgments were estimated using item response theory. Analyzing them together with standard risk factors for diabetes comorbidities showed that the different types of data describe different aspects of a patient’s situation. These aspects occasionally overlap, but not in any particularly useful way. They both provide important information to decision makers, and neither is necessarily more relevant than the other. Both should therefore be considered, to achieve a more complete evaluation of diabetes care and to promote person-centered care

Patient-reported outcome and experience measures for diabetes: development of scale models, differences between patient groups and relationships with cardiovascular and diabetes complication risk factors, in a combined registry and survey study in Sweden

Purpose The Swedish National Diabetes Register (NDR) has developed a diabetes-specific questionnaire to collect information on individuals' management of their diabetes, collaboration with healthcare providers and the disease’s impact on daily life. Our main objective was to develop measures of well-being, abilities to manage diabetes and judgements of diabetes care, and to detect and quantify differences using the NDR questionnaire. Design, setting and participants The questionnaire was analysed with using responses from 3689 participants with type 1 and 2 diabetes, randomly sampled from the NDR population, combined with register data on patient characteristics and cardiovascular and diabetes complication risk factors. Methods We used item response theory to develop scales for measuring well-being, abilities to manage diabetes and judgements of diabetes care (scores). Test–retest reliability on the scale level was analysed with intraclass correlation. Associations between scores and risk factor levels were investigated with subgroup analyses and correlations. Results We obtained scales with satisfactory measurement properties, covering patient reported outcome measures such as general well-being and being free of worries, and patient reported experience measure, for example, access and continuity in diabetes care. All scales had acceptable test–retest reliability and could detect differences between diabetes types, age, gender and treatment subgroups. In several aspects, for example, freedom of worries, type 1 patients report lower than type 2, and younger patients lower than older. Associations were found between some scores and glycated haemoglobin, but none with systolic blood pressure or low-density lipoprotein cholesterol. Clinicians report positive experience of using scores, visually presented, in the patient dialogue. Conclusions The questionnaire measures and detects differences in patient well-being, abilities and judgements of diabetes care, and identifies areas for improvement. To further improve diabetes care, we conclude that patient-reported measures are important supplements to cardiovascular and diabetes complication risk factors, reflecting patient experiences of living with diabetes and diabetes care

New Diabetes Questionnaire to add patients’ perspectives to diabetes care for adults with type 1 and type 2 diabetes: nationwide cross-sectional study of construct validity assessing associations with generic health-related quality of life and clinical variables

Objectives To study evidence for construct validity, the aim was to describe the outcome from the recently developed Diabetes Questionnaire, assess the associations of that outcome with clinical variables and generic health-related quality of life, and study the sensitivity to differences between clinically relevant groups of glycaemic control in adults with type 1 and type 2 diabetes in a nation-wide setting.Design Cross-sectional survey.Setting Swedish diabetes care clinics connected to the National Diabetes Register (NDR).Participants Among 2479 adults with type 1 diabetes and 2469 with type 2 diabetes selected at random from the NDR, 1373 (55.4%) with type 1 and 1353 (54.8%) with type 2 diabetes chose to participate.Outcome measures The Diabetes Questionnaire, the generic 36-item Short Form version 2 (SF-36v2) health survey and clinical variables.Results Related to the prespecified assumptions, supporting evidence for construct validity for the Diabetes Questionnaire was found. Supporting divergent validity, the statistically significant correlations with the clinical variables were few and weak. In relation to the SF-36v2 and in support of convergent validity, the strongest correlations were seen in the Diabetes Questionnaire scales General Well-being and Mood and Energy. In those scales, machine learning analyses showed that about 40%–45% of the variance was explained by the SF-36v2 results and clinical variables. In multiple regression analyses among three groups with differing levels of glycated haemoglobin adjusted for demographics, other risk factors, and diabetes complications, the high-risk group had, in support of sensitivity to clinically relevant groups, statistically significant lower scores than the well-controlled group in most Diabetes Questionnaire scales.Conclusions This nation-wide study shows that the Diabetes Questionnaire captures some generic health-related quality-of-life dimensions, in addition to adding diabetes-specific information not covered by the SF-36v2 and clinical variables. The Diabetes Questionnaire is also sensitive to differences between clinically relevant groups of glycaemic control

A disease-specific questionnaire for measuring patient-reported outcomes and experiences in the Swedish National Diabetes Register : Development and evaluation of content validity, face validity, and test-retest reliability

Objective: To describe the development and evaluation of the content and face validity and test-retest reliability of a disease-specific questionnaire that measures patient-reported outcomes and experiences for the Swedish National Diabetes Register for adult patients who have type 1 or type 2 diabetes. Methods: In this methodological study, a questionnaire was developed over four phases using an iterative process. Expert reviews and cognitive interviews were conducted to evaluate content and face validity, and a postal survey was administered to evaluate test-retest reliability. Results: The expert review. s and cognitive interview. s found the disease-specific questionnaire to be understandable, with relevant content and value for diabetes care. An item-level content validity index ranged from 0.6-1.0 and a scale content validity/average ranged from 0.7-1.0. The fourth version, with 33 items, two main parts and seven dimensions, was answered by 972 adults with type 1 and type 2 diabetes (response rate 61%). Weighted Kappa values ranged from 0.31-0.78 for type 1 diabetes and 0.27-0.74 for type 2 diabetes. Conclusions: This study describes the initial development of a disease-specific questionnaire in conjunction with the NDR. Content and face validity were confirmed and test-retest reliability was satisfactory. Practice implications: With the development of this questionnaire, the NDR becomes a clinical tool that contributes to further understanding the perspectives of adult individuals with diabetes