BACKGROUND AND PURPOSE:The Unidimensional Fatigue Impact Scale (U-FIS) was developed for use in a multiple sclerosis population. The aim was to determine whether the U-FIS is a valid tool for measuring the impact of fatigue in Crohn's disease (CD).METHOD:CD patients completed the U-FIS as part of a validation study of the Crohn's Life Impact Questionnaire (CLIQ). Data were analyzed according to Rasch measurement theory (RMT).RESULTS:Two hundred sixty-one completed U-FIS questionnaires were available for analysis. After rescoring the items to resolve disordered thresholds, all 22 items showed acceptable RMT fit. However, there was considerable local item dependency (LID).CONCLUSION:The U-FIS did not provide unidimensional measurement in a sample of CD patients due to high levels of LID. Combining the three FIS outcomes into a single measure was not justified.

Over the past 40 years literally thousands of generic and disease specific patient reported outcome (PRO) instruments have been developed. While most were developed for a specific study and were never used again, there is still the question of how manufacturers and others should select a PRO instrument for a study. These studies may be clinical pivotal trials or observational tracking studies to support therapy response. Formulary committees also need to be able to interpret PRO data to make decisions about whether to accept claims for therapy response. It is possible to argue that the many different approaches to outcome measurement have resulted from the lack of agreed methodologies. However, a more likely explanation is that the authors have failed to apply the axioms of fundamental measurement when creating their measures. The result is a plethora of ordinal PRO instruments that inform little about the impact of interventions. Clinical trials rarely report PRO data. Where they do, analyses are generally restricted to (for example) changes in the experimental group’s scores. Comparisons between the treatment and placebo groups or between active groups are infrequently reported, most likely due to the failure of the instrument to show differences or changes in outcome. This is unfortunate as it means no assessment is made of the value that patients gain from the intervention. This commentary is intended to make researchers and formulary committees aware of the issues that need to be addressed when selecting PRO instruments for a study or evaluating publications and claims for therapy response. The latter is crucial as reported data influence the selection of medicines and healthcare products. In the latter case a particular concern is with PRO claims embedded in simulation models.

We are grateful for the letter from Mokkink and colleagues concerning our article, “Setting and maintaining standards for patient-reported outcome measures: Can we rely on the COSMIN checklists?”. We appreciate their acknowledgment of our purpose and acceptance of many of the points we raised. Rather than reiterate our concerns, we would like to focus on specific issues raised by the letter. We still feel that there are gaps in the COSMIN process. Mokkink et al. point out that they cannot be held responsible for how people apply their recommended procedures and that reviewers should be experts in patient-reported outcome measures (PROMs). This is of course true, but the lack of expertise apparent in many of the COSMIN reviews will always occur, with many unqualified people continuing to undertake reviews, claiming that they apply the COSMIN procedures. The COSMIN standards required to evaluate the PROMs are still vague, leaving reviewers to make subjective decisions. Consequently, readers must check for themselves the articles reviewed to judge their quality. Mokkink and colleagues report that the COSMIN Risk of Bias checklist uses a worst-score rating per study and argue that it is difficult to meet the stated standards. However, Terwee and colleagues use the example of “Reliability” (Box B) to provide a general description of the scoring system used. It should be noted that reproducibility (reliability) is a crucial statistic for evaluating the quality of instruments. Each issue in the risk of bias boxes is given a score on a four-point rating system running from “excellent” to “poor”. Descriptions of the four ratings follow:

As test-developers we have often been troubled by published reviews of patient-reported outcome measures (PROMs). Too often minor issues are judged important while other reviews exclude the best measures available. Perhaps this led several groups to make recommendations for evaluating the quality of PROMs. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist is the latest set of recommendations. While reviewing the COSMIN literature and reviews conducted using their recommendations several concerns became apparent. The checklist is not evidence-based, relying on the opinion of researchers experienced in health-related quality of life. PROMs measuring other types of outcomes are inadequately covered by the checklist. COSMIN choose to focus on Classical Test Theory and the checklists are not appropriate for use with PROMs developed using modern measurement. Such an approach only obstructs progress in the field of outcome measurement. The retrospective nature of the evaluations also penalizes new PROMs. While the checklists imply that composite, ordinal level measurement is acceptable, crucial aspects of instrument development and quality are excluded. Reviews based on the COSMIN checklist produce contradictory conclusions and fail to provide evidence to support the recommendations. These problems suggest that the checklists themselves lack reliability and validity. It is also clear that several reviewers lack the expertise to apply the checklists. Researchers require a good grounding in instrument development and psychometrics to produce quality reviews. The science of modern PROM development is still in an early phase. Few available PROMs have sufficient quality, limiting the need for complex reviews. Standards need to be agreed for high quality outcome measurement. The issue is who should set these standards? Most published reviews merely scratch the surface and lack essential detail. All reviews of PROMs should be treated with caution, irrespective of whether the COSMIN checklist was employed.

INTRODUCTION:Psoriatic arthritis (PsA) is a multifaceted inflammatory disease that can cause joint destruction and impair quality of life. The Psoriatic Arthritis Quality of Life Questionnaire (PsAQoL) was the first disease-specific tool for determining the impact of the disease on the quality of life of people with PsA.OBJECTIVES:The primary objective was to develop and validate a Brazilian Portuguese version of the PsAQoL.METHODS:The UK PsAQoL was translated into Brazilian Portuguese using two translation panels. This translation then checked for face validity and construct validity with new samples of patients. Finally, a test-retest validation study was conducted with 52 patients with PsA. The survey included the Nottingham Health Profile (NHP) as a comparator instrument.RESULTS:Internal consistency and reproducibility were both excellent for the new adaptation (0.91 and 0.90 respectively Scores on the PsAQoL were found to correlate as expected with the comparator measure and the instrument was able to detect differences in score related to perceived severity of PsA, general health status and presence of a flare.CONCLUSION:The Brazilian PsAQoL was found easy to understand and complete and has excellent reliability and construct validity. The new measure will be a valuable new tool for use in routine PsA practice and clinical trials.

OBJECTIVE:To test the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) according to Rasch Measurement Theory and investigate whether measurement precision can be improved.METHODS:Secondary analysis of a BASDAI database. The data had been collected from individuals starting an Ankylosing Spondylitis Exercise Course at the Royal National Hospital for Rheumatic Diseases in Bath, UK.RESULTS:Data were available for 250 participants (23.6% female) aged between 18 and 85 years (mean 52.8, SD 14.6). Initial fit of the data to the Rasch model appeared good and item thresholds were consistent, but local item dependence (LID) was identified. After addressing the LID, a unidimensional measure was achieved. The Person Separation Index (reliability) was 0.83 and the location of the items was well matched to that of the respondents. A transformation table was generated to convert total raw BASDAI scores into linearized Rasch transformed scores that form an interval scale. The Smallest Detectable Difference improved from 2 to 1.2. This finding suggests that a change score of > 1.2 points on the modified BASDAI is required to achieve meaningful change.CONCLUSION:Applying the Rasch transformed scores simplifies completion and scoring of the measure and confirms internal construct validity. It also ensures linear measurement and justifies the use of parametric statistical analyses when analyzing datasets. The transformation table can be used with existing BASDAI datasets to allow direct comparisons of disease activity scores with those generated from future studies.

Composite measures that combine different types of indicators are widely used in medical research; to evaluate health systems, as outcomes in clinical trials and patient-reported outcome measurement. The potential advantages of such indices are clear. They are used to summarise complex data and to overcome the problem of evaluating new interventions when the most important outcome is rare or likely to occur far in the future. However, many scientists question the value of composite measures, primarily due to inadequate development methodology, lack of transparency or the likelihood of producing misleading results. It is argued that the real problems with composite measurement are related to their failure to take account of measurement theory and the absence of coherent theoretical models that justify the addition of the individual indicators that are combined into the composite index. All outcome measures must be unidimensional if they are to provide meaningful data. They should also have dimensional homogeneity. Ideally, a specification equation should be developed that can predict accurately how organisations or individuals will score on an index, based on their scores on the individual indicators that make up the measure. The article concludes that composite measures should not be used as they fail to apply measurement theory and, consequently, produce invalid and misleading scores.

BACKGROUND:Pulmonary hypertension (PH) results in severely impaired quality of life (QoL) in people with this condition. The CAMbridge Pulmonary Hypertension Outcome Review (CAMPHOR) is the only questionnaire providing a disease-specific measurement of symptoms, functioning and QoL in PH patients. It has already been adapted for use in several countries. The aim of this study was to adapt and validate CAMPHOR for the Polish-speaking population.METHODS:Two panels (bilingual and lay) were conducted to translate CAMPHOR into Polish. This new version was then tested by cognitive debriefing interviews with 15 patients. Finally, a postal validation survey was conducted with 56 patients on two occasions 2 weeks apart to assess its psychometric properties.RESULTS:No problems were experienced in producing a Polish translation of CAMPHOR. Interviewees responded well to the Polish CAMPHOR, finding it relevant, comprehensible and easy to complete. For all three CAMPHOR scales (Symptoms, Activity, QoL), The Cronbach alpha coefficients were above 0.8 at both time points, indicating high internal consistency. Test-retest reliability for the three scales achieved a value above 0.80. Predicted correlations with the Nottingham Health Profile provided evidence of the construct validity of CAMPHOR scales. The Polish CAMPHOR could distinguish between patients who differed according to their perceived general health and perceived disease severity. No significant differences in scores were found between participants grouped by gender or age.CONCLUSIONS:The Polish version of CAMPHOR demonstrated good psychometric properties and is recommended for use in clinical practice.

Aim: Informal caregivers play a vital role in the care of people with Alzheimer’s Disease (AD), yet caregiving is associated with caregivers’ burden. The initial objective of the study was to develop a new outcome measure to assess quality of life (QoL) in AD caregivers. Methods: Informal (non-professional) caregivers providing 75% or more of the care activities for, and living in the same household as, a person with AD were invited to take part in the study. Qualitative interviews (N = 40) were conducted with AD caregivers in the UK and thematic analyses were applied to generate a pool of potential items. A draft questionnaire was produced and adapted for use in Italy, Spain, Germany and the US. In each of the 5 countries, cognitive debriefing interviews (N = 76) were conducted to determine the questionnaire’s face and content validity, followed by a postal validation survey (N = 268). The data from these surveys were combined to reduce the number of items and assess the new questionnaire’s psychometric properties. Results: Thematic analysis of the UK interview transcripts generated a draft questionnaire, which was successfully translated into each additional language. The items were well accepted and easy to complete. However, reanalysis of the qualitative interview data revealed that spousal and non-spousal caregivers identified different experiences of caregiving. A review of the item pool indicated that items were primarily targeted at spousal caregivers. Therefore, further analyses of the postal survey data included spousal caregivers only (n = 116). The results supported scaling assumptions (e.g., corrected item-total correlations ≥0.32), targeting (e.g., floor/ceiling effects <2.5%), internal consistency (α ≥0.93) and test-retest reliability (rs = 0.88) of the new questionnaire, according to classical test theory. Assessment of external construct validity yielded results in accordance with a priori expectations. QoL scores were most strongly related to scores on the emotional reactions sections of the Nottingham Health Profile and the General Well-Being Index. The new questionnaire was found to be capable of detecting meaningful differences between respondents; spousal caregivers had worse QoL when the person with AD was confused (p < .001), could not be left alone (p < .001), did not recognize the caregiver (p < .001), was incontinent (p < .05), and wandered around the house (p = .01). Conclusions: The Alzheimer’s Disease Patient Partners Life Impact Questionnaire (APPLIQue) is a questionnaire specific to spousal caregivers of people with AD. Data support its scaling assumptions and it exhibits excellent psychometric properties according to classical test theory. The questionnaire is recommended for use in intervention studies where the QoL of spousal caregivers is of interest.

Background: The Nottingham Health Profile (NHP) is a generic measure of perceived distress that has been used widely as an outcome measure in clinical practice and trials. The availability of two Brazilian datasets provided the opportunity to assess the psychometric performance of the NHP in different populations - adult growth hormone deficiency (GHD) and pulmonary hypertension (PH). The purpose of the study was to see how valuable the NHP could be in assessing outcomes in diseases where no disease-specific measures are available. Methods: Secondary analyses were performed with NHP data. Patients diagnosed with adult GHD or PH were administered the NHP during clinic visits on two occasions, two weeks apart. A disease-specific measure of quality of life (QoL) was also administered to the relevant sample of patients on each occasion. Results: The psychometric properties of the NHP were good for both disease groups. As expected, both samples reported high scores on energy level, the PH sample scored high on physical functioning and the GHD sample on emotional reactions. For both samples, most of the NHP sections were able to distinguish between groups of respondents with different ratings of perceived general health. While most sections of the NHP were relatively highly correlated with the QoL measures, pain and sleep did not seem to be important predictors of QoL in either of the samples. Conclusions: The use of the NHP in adult GHD and PH populations in Brazil is not recommended as there are high-quality disease-specific measures available for each disease. However, where no disease-specific measures are available, the NHP can provide good descriptive information of the impact of disease on different patient populations.

Abstract Background Pulmonary Hypertension (PH) impacts negatively on patients’ health-related quality of life (HRQoL). The Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) was the first PH-specific and validated instrument for use in different languages worldwide. This report describes the adaptation and psychometric validation of the CAMPHOR into Brazilian Portuguese language. Methods The translation and validation process included a bilingual and lay panel translation; cognitive debriefing interviews; psychometric testing in two repeated times assessing internal consistency, reproducibility and validity of the questionnaire. The Nottingham Health Profile (NHP) questionnaire was used as a comparator to test for convergent validity. Results The translation captured the same concepts as the English questionnaire and produced a comprehensive instrument in a Brazilian-Portuguese version expressing common, natural language. The psychometric evaluation involved 102 patients (48.8 ± 14.5 years, 80,4% female]. Cronbach’s alpha coefficients were above 0.9 on all three CAMPHOR scales. There was excellent test-retest reliability (coefficients above 0.85 on all scales). CAMPHOR Symptoms scale and Activities scale correlated highly with Physical Mobility section and CAMPHOR QoL scale was strongly associated with the Emotional Reactions and Social Isolation sections of NHP. There was a significant association between gender and perceived general health (p < 0.05). There were significant differences in CAMPHOR scale scores between patients who differed according to their perceived disease severity and general health. Conclusions The present CAMPHOR version demonstrated good psychometric properties and provides a reliable instrument for assessing HRQL and QoL in Brazilian PH patients, addressing patients’ perspective of their illness in a comprehensive way.

Rheumatoid arthritis (RA) is a chronic disease with an enormous impact on patients’ quality of life. The Rheumatoid Arthritis Quality of Life (RAQoL) questionnaire is a disease-specific measure of QoL for individuals with rheumatoid arthritis. Our aim was to adapt and validate the RAQoL for use in Bulgaria. The development of a new language version of the RAQoL consisted of three stages: translation, field testing and psychometric evaluation. The dual-panel methodology, requiring two independent panels of Bulgarian speakers, was applied to translate the UK English version of the RAQoL into Bulgarian. Face and content validity of the translated questionnaire were assessed through cognitive debriefing interviews. Lastly, the RAQoL was administered on two occasions to a random sample of RA patients to evaluate reliability and validity. At the first occasion, the SF-36 was also administered for use as a comparator scale. The RAQoL was successfully adapted into Bulgarian and considered easy to understand, acceptable and comprehensive by RA patients. A psychometric study demonstrated that the new language version has excellent internal consistency (Cronbach’s alpha coefficients = 0.93 and 0.94) and test–retest reliability (a Spearman’s rank correlation coefficient = 0.97). Convergent validity was established by correlating scores on the RAQoL with a comparator measure, the SF-36. A strong correlation between RAQoL scores and the physical functioning section of the SF-36 was observed. Known group validity was established by the ability of the measure to distinguish between subgroups of patients, who differed according to their perceived general health, disease severity (p < 0.001) and whether they were experiencing a flare-up (p < 0.01). The new language version is recommended for use in future research studies, clinical trials and routine practice with Bulgarian RA patients.

The Needs-based model of quality of life has been employed in the development of a wide range of disease-specific quality of life measures over the last 20 years. The model argues that disease prevents need fulfilment and that effective interventions enable individuals to satisfy more of their fundamental human needs. Rather than adopting an existing theoretical framework, the needs-based model developed through grounded theory techniques. Several theories of needs have been advanced during the last 70 years, many of which are well known. This article relates the needs-based model of quality of life to the major published theories of human needs. Several of the theories focus on the development of societies rather than individuals – dependent on the disciplines and interests of the authors; who include sociologists, economists and psychologists. Most theorists also believe that there is a hierarchy of needs. The needs theories suggest that there are varying numbers of fundamental needs, but these tend to overlap across the theories. Statistical analyses of data collected with the needs-based quality of life measures support the view that there is a single, fundamental need.

ABSTRACT Background To develop and validate a patient‐reported outcome (PRO) measure of quality of life (QoL), specific to patients with Neurofibromatosis Type 1 (NF1)‐associated plexiform neurofibromas (pNFs), suitable for use in clinical efficacy trials. The study was conducted in parallel in the UK and US. Methods Qualitative interviews were conducted with patients to generate questionnaire content. Face and content validity of the draft scale was assessed by cognitive debriefing interviews (CDIs). A postal validation survey was conducted to identify the final version of the questionnaire (the PlexiQoL), establish its unidimensionality, and assess its psychometric properties. Results Thematic analysis was performed on 42 interview transcripts. Thirty‐one CDIs revealed that patients found the draft scale to be comprehensible, relevant, and easy to complete. The postal validation survey was completed by 273 patients. Rasch analysis identified an 18‐item unidimensional scale that showed excellent internal consistency, reproducibility, and sensitivity to differences in patient‐perceived pNF severity, general health, and the use of pain medication. Conclusions The PlexiQoL is the first disease‐specific PRO assessing the ability of adults with NF‐1 associated pNFs to meet their basic human needs. Clinical trials are planned to assess the sensitivity to change of the PlexiQoL in people undergoing treatment for pNFs.

ABSTRACT Objective: To conduct a cross-cultural adaptation of the Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) as an instrument to evaluate the perception of symptoms, functional limitation, and health-related quality of life (HRQoL) in subjects diagnosed with pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH) in Colombia. Methods: The adaptation process involved 3 phases: translation, cognitive debriefing interviews, and a validation survey. To evaluate the psychometric properties, we recruited individuals ≥ 18 years of age who had been diagnosed with PAH or CTEPH to take part in the latter two stages of the adaptation process. All individuals were being followed on an outpatient basis by the pulmonary hypertension programs at Hospital Universitario San Ignacio, Fundación Clínica Shaio,and Clínicos IPS, all located in the city of Bogotá, Colombia. Results: A Spanish-language version of the CAMPHOR was developed for use in Colombia. The internal consistency was excellent for the symptoms, functioning, and quality of life scales (Cronbach’s alpha coefficients of 0.92, 0.87, and 0.93, respectively). Test-retest reliability was above 0.70. The evaluation of the convergent validity and known group validity of the CAMPHOR scales confirmed that there were moderate and strong correlations with the related constructs of the Medical Outcomes Study 36-item Short-Form Health Survey, version 2, as well as showing their capacity to discriminate disease severity. Conclusions: The Spanish-language version of the CAMPHOR developed for use in Colombia was the result of a translation and cultural adaptation process that allows us to consider it equivalent to the original version, having shown good psychometric properties in the study sample. Therefore, its use to assess the impact of interventions on the HRQoL of patients with PAH or CTEPH is recommended, in research and clinical practice.

Background & aims: Home parenteral nutrition (HPN) provides life sustaining treatment for people with chronic intestinal failure. Individuals may require HPN for months or years and are dependent on regular intravenous infusions, usually 12-14 h overnight between 1 and 7 days each week. This regime can have adverse impact on the life of people dependent on the treatment. The aim of this study was to establish mean values for the Parenteral Nutrition Impact Questionnaire (PNIQ) and to determine the effect of disease, frequency of infusions per week and patient characteristics on quality of life of patients fed HPN. Method: The PNIQ was distributed to patients across nine UK HPN clinics. Data were analysed using linear regression, with PNIQ score as the dependent variable and potential confounders as independent variables. Unadjusted and adjusted models are presented. Higher PNIQ scores reflect poorer quality of life. Results: Completed questionnaires were received from 466 people dependent on HPN. Mean PNIQ score was 11.04 (SD 5.79). A higher PNIQ score (effect size 0.52, CI 0.184 to 0.853) was recorded in those dependent on a higher frequency of HPN infusions per week. Respondents with cancer had a similar mean PNIQ score to those with inflammatory bowel disease (mean 10.82, SD 6.00 versus 11.04, SD 5.91). Those with surgical complications reported a poorer QoL (effect size 3.03, CI 0.642 to 5.418) and those with severe gastro-intestinal dysmotility reported a better QoL (effect size 3.03, CI -5.593 to -0.468), compared to other disease states. Conclusions: This large cohort study of quality of life in chronic intestinal failure demonstrates that HPN impacts individuals differently depending on their underlying disease. Furthermore, since the number of HPN infusions required per week is inversely related to an individual's needs-based quality of life, therapies that reduce PN burden should lead to an improvement in QoL. (C) 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Pulmonary hypertension (PH) is a chronic disease which severely impairs quality of life (QoL). The Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) is the first disease-specific tool to assess patient-reported symptoms, functioning and QoL in PH patients. The aim of this study was to adapt and validate the CAMPHOR for use in Croatia. The adaptation process involved three stages: translation (bilingual and lay panel), cognitive debriefing interviews with patients and psychometric validation. For the latter stage, a postal survey was conducted with 50 patients to examine the reliability and validity of the adapted scale. All three scales of the Croatian CAMPHOR demonstrated excellent internal consistency (Symptoms = 0.93; Activity limitations = 0.94; QoL = 0.92) and test-retest reliability correlations (Symptoms = 0.90; Activity limitations = 0.95; QoL = 0.90). Predicted correlations with the SF-36 scales provided evidence for construct validity of the CAMPHOR scales. Evidence for known group validity was shown by the ability of the scales to distinguish between participants based on patient-perceived general health and disease severity. The Croatian version of the CAMPHOR is a valid and reliable tool for use in clinical routine and clinical research.