Validity of a condition specific outcome measure for fragile X syndrome: the Aberrant Behaviour Checklist-utility index

A scoping review to create a framework for the steps in developing condition-specific preference-based instruments de novo or from an existing non-preference-based instrument: use of item response theory or Rasch analysis

BACKGROUND

There is no widely accepted framework to guide the development of condition-specific preference-based instruments (CSPBIs) that includes both de novo and from existing non-preference-based instruments. The purpose of this study was to address this gap by reviewing the published literature on CSPBIs, with particular attention to the application of item response theory (IRT) and Rasch analysis in their development.

METHODS

A scoping review of the literature covering the concepts of all phases of CSPBI development and evaluation was performed from MEDLINE, Embase, PsychInfo, CINAHL, and the Cochrane Library, from inception to December 30, 2022.

RESULTS

The titles and abstracts of 1,967 unique references were reviewed. After retrieving and reviewing 154 full-text articles, data were extracted from 109 articles, representing 41 CSPBIs covering 21 diseases or conditions. The development of CSPBIs was conceptualized as a 15-step framework, covering four phases: 1) develop initial questionnaire items (when no suitable non-preference-based instrument exists), 2) establish the dimensional structure, 3) reduce items per dimension, 4) value and model health state utilities. Thirty-nine instruments used a type of Rasch model and two instruments used IRT models in phase 3.

CONCLUSION

We present an expanded framework that outlines the development of CSPBIs, both from existing non-preference-based instruments and de novo when no suitable non-preference-based instrument exists, using IRT and Rasch analysis. For items that fit the Rasch model, developers selected one item per dimension and explored item response level reduction. This framework will guide researchers who are developing or assessing CSPBIs.

Impact of developmental and epileptic encephalopathies on caregivers: A literature review

OBJECTIVES

Developmental and epileptic encephalopathies (DEEs) are rare neurodevelopmental disorders characterized by early-onset seizures and numerous comorbidities. Due to the complex requirements for the care of a child with a DEE, these disorders would be expected to impact health-related quality of life (HRQL) for caregivers as well as for patients. The objective of this literature review was to describe the impact of DEEs on the HRQL, emotional wellbeing, and usual activities (social, work, relationships, etc.) of caregivers, including the wider impact on other family members such as siblings.

METHODS

A literature search was conducted in May 2020 using MEDLINE® and Embase® databases. Quantitative and qualitative studies were identified using search terms related to family, disease type (including >20 specific DEEs), and quality of life/methodology. Each study was assessed for relevance and was graded using customized critical appraisal criteria. Findings from studies that were given the highest quality ratings were summarized and used to develop a conceptual model to illustrate the complex impact of DEEs on caregiver HRQL.

RESULTS

Sixty-seven relevant studies were identified, of which 39 (27 quantitative, 12 qualitative) met the highest appraisal criteria. The studies recruited caregivers of patients with one of eight individual DEEs, or pediatric intractable or refractory epilepsy. Most studies reported negative impacts on HRQL and emotional wellbeing in caregivers. The wide-ranging impact of a DEE was highlighted by reports of negative effects on caregivers' physical health, daily activities, relationships, social activities, leisure time, work, and productivity. Factors that influenced the perceived impact included demographic characteristics (e.g., child's age, living arrangements, family income) and clinical factors (e.g., feeding or sleep difficulties, disease severity). Few studies evaluated the impact on siblings.

CONCLUSIONS

There is evidence that DEEs can impact HRQL and emotional wellbeing and can limit usual activities for the primary caregiver and their wider family. However, no research was identified regarding many individual DEEs, and only limited research assessed the impact on different family members with most studies focusing on mothers. Further research is required to understand the influence of certain factors such as the age of the patient, disease severity, and seizures on caregiver burden. Furthermore, the review highlighted the lack of appropriate measurement tools to assess caregiver HRQL in this population.

Quantifying the economic impact of caregiving for Duchenne muscular dystrophy (DMD) in Spain

AIM

To establish the potential economic burden in caregivers to patients with DMD and the potential causative factors.

METHOD

Caregivers to patients with DMD were recruited through the DMD patients Register and questioned about several economic aspects using "ad-hoc" questionnaires.

RESULTS

All families, apart from one (97.2% n = 36), incurred in monthly medical costs (44% of the families more than 50 euros/month). 97.2% of the households considered looking after a patient of DMD as financially burdensome, and 80.5% of households declared to have suffered work changes, especially the mothers (job timetable-related mainly). The presence of obsessive-compulsive disorders (OCD) in patients was significantly associated with caregivers' high financial burden as these were six times more likely to have this perception OR = 6468 IC 95% (1056-39,601), p = 0.043. Also, when patients had learning difficulties, caregivers had up to six times more chances to incur in monthly expenditure for formal care OR = 6089 IC 95% (1112-33,342), p = 0.037.

INTERPRETATION

Caregivers have relevant financial burden that might be conditioned by the clinical condition of the patient.

WHAT THIS PAPER ADDS

Quantitative data about financial burden in DMD Spanish families providing informal care. Identification of the patient's main clinical issues associated with financial burden.

Patterns, trends and methodological associations in the measurement and valuation of childhood health utilities

PURPOSE

To systematically assess patterns and temporal changes in the measurement and valuation of childhood health utilities and associations between methodological factors.

METHODS

Studies reporting childhood health utilities using direct or indirect valuation methods, published by June 2017, were identified through PubMed, Embase, Web of Science, PsycINFO, EconLit, CINAHL, Cochrane Library and PEDE. The following were explored: patterns in tariff application; linear trends in numbers of studies/samples and paediatric cost-utility analyses (CUAs) and associations between them; changes in proportions of studies/samples within characteristic-based categories over pre-specified periods; impact of National Institute for Health and Care Excellence (NICE) guidance on primary UK research and associations between valuation method, age and methodological factors.

RESULTS

335 studies with 3974 samples covering all ICD-10 chapters, 23 valuation methods, 12 respondent types and 42 countries were identified by systematic review. 34.0% of samples using indirect methods compatible with childhood applied childhood-derived tariffs. There was no association between numbers of studies/samples and numbers of CUAs. Compared to 1990-2008, 2009-June 2017 saw a significant fall in the proportion of studies using case series; significant compositional changes across ICD-10 chapters and significantly higher sample proportions using childhood-specific and adult-specific indirect valuation methods, and based on pre-adolescents, self-assessment, self-administration and experienced health states. NICE guidance was weakly effective in promoting reference methods. Associations between valuation method, age and methodological factors were significant.

CONCLUSION

1990-2017 witnessed significant changes in primary research on childhood health utilities. Health technology assessment agencies should note the equivocal effect of methodological guidance on primary research.

Updated report on tools to measure outcomes of clinical trials in fragile X syndrome

OBJECTIVE

Fragile X syndrome (FXS) has been the neurodevelopmental disorder with the most active translation of preclinical breakthroughs into clinical trials. This process has led to a critical assessment of outcome measures, which resulted in a comprehensive review published in 2013. Nevertheless, the disappointing outcome of several recent phase III drug trials in FXS, and parallel efforts at evaluating behavioral endpoints for trials in autism spectrum disorder (ASD), has emphasized the need for re-assessing outcome measures and revising recommendations for FXS.

METHODS

After performing an extensive database search (PubMed, Food and Drug Administration (FDA)/National Institutes of Health (NIH)'s www.ClinicalTrials.gov, etc.) to determine progress since 2013, members of the Working Groups who published the 2013 Report evaluated the available outcome measures for FXS and related neurodevelopmental disorders using the COSMIN grading system of levels of evidence. The latter has also been applied to a British survey of endpoints for ASD. In addition, we also generated an informal classification of outcome measures for use in FXS intervention studies as instruments appropriate to detect shorter- or longer-term changes.

RESULTS

To date, a total of 22 double-blind controlled clinical trials in FXS have been identified through www.ClinicalTrials.gov and an extensive literature search. The vast majority of these FDA/NIH-registered clinical trials has been completed between 2008 and 2015 and has targeted the core excitatory/inhibitory imbalance present in FXS and other neurodevelopmental disorders. Limited data exist on reliability and validity for most tools used to measure cognitive, behavioral, and other problems in FXS in these trials and other studies. Overall, evidence for most tools supports a moderate tool quality grading. Data on sensitivity to treatment, currently under evaluation, could improve ratings for some cognitive and behavioral tools. Some progress has also been made at identifying promising biomarkers, mainly on blood-based and neurophysiological measures.

CONCLUSION

Despite the tangible progress in implementing clinical trials in FXS, the increasing data on measurement properties of endpoints, and the ongoing process of new tool development, the vast majority of outcome measures are at the moderate quality level with limited information on reliability, validity, and sensitivity to treatment. This situation is not unique to FXS, since reviews of endpoints for ASD have arrived at similar conclusions. These findings, in conjunction with the predominance of parent-based measures particularly in the behavioral domain, indicate that endpoint development in FXS needs to continue with an emphasis on more objective measures (observational, direct testing, biomarkers) that reflect meaningful improvements in quality of life. A major continuous challenge is the development of measurement tools concurrently with testing drug safety and efficacy in clinical trials.