Development and validation of meta-measurement instruments: A methodological approach.

A valid and reliable nursing assessment is essential for identifying required care and ensuring patient safety. The convenience of conducting a comprehensive assessment of the patient has led to a significant increase in assessment tools that may slow down the process. Nevertheless, the possibility of consolidating various instruments that measure common or similar constructs into a meta-instrument is considered an alternative that could enhance assessment efficiency. A meta-instrument can be defined as a measurement tool that consolidates other instruments based on measuring related constructs and sharing dimensions or items, aiming to achieve a more parsimonious measurement. Literature on such assessment tools is scarce, and there are numerous options for their construction and initial validation. Additionally, it is advisable to confirm their psychometric properties and ensure that they maintain, at the very least, the same diagnostic capacity as the original instruments. This article presents a proposal for the phases to follow in constructing meta-instruments, along with various methodological alternatives that can be employed based on the characteristics of the original instruments and the purpose of creating the meta-instrument. Furthermore, special attention is given to the checklists that should be used to study the psychometric properties and diagnostic capacity of the meta-instruments. Finally, future lines of research and challenges in the development of nursing assessment meta-instruments are discussed.

A systematic review of sham acupuncture validation studies.

BACKGROUND: Acupuncture is widely used worldwide; however, studies on its effectiveness have been impeded by limitations regarding the design of appropriate control groups. In clinical research, noninvasive sham acupuncture techniques can only be applied through validation studies. Therefore, this systematic review aimed to evaluate the scope of existing literature on this topic to identify trends. METHODS: We queried Pubmed, EMBASE, and the Cochrane Central Register of Controlled Trials databases from inception to July 2022 for relevant articles. Author names were used to identify additional relevant articles. Two independent reviewers assessed the identified articles based on the inclusion and exclusion criteria. The following data were extracted: study design, information regarding acupuncturists and participants, general and treatment-related characteristics of the intervention and control groups, participants' experience of acupuncture, and research findings. RESULTS: The database query yielded 673 articles, of which 29 articles were included in the final review. Among these, 18 involved the use of one of three devices: Streitberger (n = 5), Park (n = 7), and Takakura (n = 6) devices. The remaining 11 studies used other devices, including self-developed needles. All the included studies were randomized controlled trials. The methodological details of the included studies were heterogeneous with respect to outcomes assessed, blinding, and results. CONCLUSIONS: Sham acupuncture validation studies have been conducted using healthy volunteers, with a focus on blind review and technological developments in sham acupuncture devices. However, theren may be language bias in our findings since we could not query Chinese and Japanese databases due to language barriers. There is a need for more efforts toward establishing control groups suitable for various acupuncture therapy interventions. Moreover, there is a need for more rigorous sham acupuncture validation studies, which could lead to higher-quality clinical studies.

Progress in the validation of nociception monitoring in guiding intraoperative analgesic therapy.

PURPOSE OF REVIEW: This article summarizes the current level of validation for several nociception monitors using a categorized validation process to facilitate the comparison of performance. RECENT FINDINGS: Nociception monitors improve the detection of a shift in the nociception and antinociception balance during anesthesia, guiding perioperative analgesic therapy. A clear overview and comparison of the validation process for these monitors is missing. RESULTS: Within a 2-year time-frame, we identified validation studies for four monitors [analgesia nociception index (ANI), nociception level monitor (NOL), surgical pleth index (SPI), and pupillometry]. We categorized these studies in one out of six mandatory validation steps: developmental studies, clinical validation studies, pharmacological validation studies, clinical utility studies, outcome improvement studies and economical evaluation studies. The current level of validation for most monitors is mainly focused on the first three categories, whereas ANI, NOL, and SPI advanced most in the availability of clinical utility studies and provide confirmation of a clinical outcome improvement. Analysis of economical value for public health effects is not yet publicly available for the studied monitors. SUMMARY: This review proposes a stepwise structure for validation of new monitoring technology, which facilitates comparison between the level of validation of different devices and identifies the need for future research questions.

Don't be misled: 3 misconceptions about external validation of clinical prediction models.

Clinical prediction models provide risks of health outcomes that can inform patients and support medical decisions. However, most models never make it to actual implementation in practice. A commonly heard reason for this lack of implementation is that prediction models are often not externally validated. While we generally encourage external validation, we argue that an external validation is often neither sufficient nor required as an essential step before implementation. As such, any available external validation should not be perceived as a license for model implementation. We clarify this argument by discussing 3 common misconceptions about external validation. We argue that there is not one type of recommended validation design, not always a necessity for external validation, and sometimes a need for multiple external validations. The insights from this paper can help readers to consider, design, interpret, and appreciate external validation studies.

Content Validity and Psychometric Properties of the German Version of the Holm and Cordoba Urinary Tract Infection Score for Uncomplicated Urinary Tract Infections in Women: Protocol for a Validation Study.

BACKGROUND: Uncomplicated urinary tract infections (UTIs) in women are among the most common bacterial infections in primary care. Given the health threats related to the overuse of antibiotics, alternative options are of increasing importance. Patient-reported outcome measures are valuable tools for including the patients' perspective when evaluating the efficacy of these strategies. Aiming to identify a suitable instrument to measure the severity and bothersomeness of UTI symptoms in women, we performed a systematic review of the literature and identified the Holm and Cordoba Urinary Tract Infection Score (HCUTI), which measures the severity, bothersomeness, and impact of uncomplicated UTIs on daily activities. This instrument showed sufficient content validity but needs translation and further validation before it can be used in German research. OBJECTIVE: For use in the German setting, we aim (1) to perform translation and linguistic validation of the HCUTI and (2) to evaluate content validity and psychometric properties of the German version of the HCUTI in a population of women with uncomplicated UTIs. METHODS: The HCUTI will be translated and linguistically validated using the dual-panel method. This process involves a bilingual translation panel and a lay panel to check the comprehensibility of the translation. Content validity of the translated questionnaire will be assessed using cognitive interviews according to the criteria for good content validity as recommended by the COSMIN (Consensus-based Standards for the selection of health Measurement Instruments) group involving women with uncomplicated UTIs and health care professionals. Subsequent psychometric validation of the German version of the HCUTI in a population of women with uncomplicated UTIs will include the assessment of structural validity, internal consistency, test-retest reliability, construct validity, responsiveness, and interpretability. RESULTS: Results of the translation and linguistic validation process and the results of the content validity study were obtained in September 2023 and will be published separately. Data on the psychometric properties of the German version of the HCUTI are anticipated in mid-2024. CONCLUSIONS: We expect that data from the content validity study will provide important suggestions for potential modifications of the HCUTI for use in the German setting. The final version of the questionnaire will be used for the assessment of its psychometric properties in a large population of women with uncomplicated UTIs. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/49903.

Measurement properties of the Mental Health Literacy Scale (MHLS) validation studies: a systematic review protocol.

INTRODUCTION: Mental Health Literacy (MHL) is important for improving mental health and reducing inequities in treatment. The Mental Health Literacy Scale (MHLS) is a valid and reliable assessment tool for MHL. This systematic review will examine and compare the measurement properties of the MHLS in different languages, enabling academics, clinicians and policymakers to make informed judgements regarding its use in assessments. METHODS AND ANALYSIS: The review will adhere to the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) methodology for systematic reviews of patient-reported outcome measures and the Joanna Briggs Institute (JBI) Manual for Evidence Synthesis and will be presented following the Preferred Reporting Items for Systematic reviews and Meta-Analysis 2020 checklist. The review will be conducted in four stages, including an initial search confined to PubMed, a search of electronic scientific databases PsycINFO, CINAHL, Scopus, MEDLINE, Embase (Elsevier), PubMed (NLM) and ERIC, an examination of the reference lists of all papers to locate relevant publications and finally contacting the MHLS original author to identify validation studies that the searches will not retrieve. These phases will assist us in locating studies that evaluate the measurement properties of MHLS across various populations, demographics and contexts. The search will focus on articles published in English between May 2015 and December 2023. The methodological quality of the studies will be evaluated using the COSMIN Risk of Bias checklist, and a comprehensive qualitative and quantitative data synthesis will be performed. ETHICS AND DISSEMINATION: Ethics approval is not required. The publication will be in peer-reviewed journals and presented at national and international conferences. PROSPERO REGISTRATION NUMBER: CRD42023430924.

GRADE concept paper 8: judging the certainty of discrimination performance estimates of prognostic models in a body of validation studies.

BACKGROUND: Prognostic models incorporate multiple prognostic factors to estimate the likelihood of future events for individual patients based on their prognostic factor values. Evaluating these models crucially involves conducting studies to assess their predictive performance, like discrimination. Systematic reviews and meta-analyses of these validation studies play an essential role in selecting models for clinical practice. METHODS: In this paper, we outline 3 thresholds to determine the target for certainty rating in the discrimination of prognostic models, as observed across a body of validation studies. RESULTS AND CONCLUSION: We propose 3 thresholds when rating the certainty of evidence about a prognostic model's discrimination. The first threshold amounts to rating certainty in the model's ability to classify better than random chance. The other 2 approaches involve setting thresholds informed by other mechanisms for classification: clinician intuition or an alternative prognostic model developed for the same disease area and outcome. The choice of threshold will vary based on the context. Instead of relying on arbitrary discrimination cut-offs, our approach positions the observed discrimination within an informed spectrum, potentially aiding decisions about a prognostic model's practical utility.

Avoiding a reproducibility crisis in regulatory toxicology-on the fundamental role of ring trials.

The ongoing transition from chemical hazard and risk assessment based on animal studies to assessment relying mostly on non-animal data, requires a multitude of novel experimental methods, and this means that guidance on the validation and standardisation of test methods intended for international applicability and acceptance, needs to be updated. These so-called new approach methodologies (NAMs) must be applicable to the chemical regulatory domain and provide reliable data which are relevant to hazard and risk assessment. Confidence in and use of NAMs will depend on their reliability and relevance, and both are thoroughly assessed by validation. Validation is, however, a time- and resource-demanding process. As updates on validation guidance are conducted, the valuable components must be kept: Reliable data are and will remain fundamental. In 2016, the scientific community was made aware of the general crisis in scientific reproducibility-validated methods must not fall into this. In this commentary, we emphasize the central importance of ring trials in the validation of experimental methods. Ring trials are sometimes considered to be a major hold-up with little value added to the validation. Here, we clarify that ring trials are indispensable to demonstrate the robustness and reproducibility of a new method. Further, that methods do fail in method transfer and ring trials due to different stumbling blocks, but these provide learnings to ensure the robustness of new methods. At the same time, we identify what it would take to perform ring trials more efficiently, and how ring trials fit into the much-needed update to the guidance on the validation of NAMs.

Validation of the Scandinavian guidelines for minor and moderate head trauma in children: protocol for a pragmatic, prospective, observational, multicentre cohort study.

INTRODUCTION: Mild traumatic brain injury is common in children and it can be challenging to accurately identify those in need of urgent medical intervention. The Scandinavian guidelines for management of minor and moderate head trauma in children, the Scandinavian Neurotrauma Committee guideline 2016 (SNC16), were developed to aid in risk stratification and decision-making in Scandinavian emergency departments (EDs). This guideline has been validated externally with encouraging results, but internal validation in the intended healthcare system is warranted prior to broad clinical implementation. OBJECTIVE: We aim to validate the diagnostic accuracy of the SNC16 to predict clinically important intracranial injuries (CIII) in paediatric patients suffering from blunt head trauma, assessed in EDs in Sweden and Norway. METHODS AND ANALYSIS: This is a prospective, pragmatic, observational cohort study. Children (aged 0-17 years) with blunt head trauma, presenting with a Glasgow Coma Scale of 9-15 within 24 hours postinjury at an ED in 1 of the 16 participating hospitals, are eligible for inclusion. Included patients are assessed and managed according to the clinical management routines of each hospital. Data elements for risk stratification are collected in an electronic case report form by the examining doctor. The primary outcome is defined as CIII within 1 week of injury. Secondary outcomes of importance include traumatic CT findings, neurosurgery and 3-month outcome. Diagnostic accuracy of the SNC16 to predict endpoints will be assessed by point estimate and 95% CIs for sensitivity, specificity, likelihood ratio, negative predictive value and positive predictive value. ETHICS AND DISSEMINATION: The study is approved by the ethical board in both Sweden and Norway. Results from this validation will be published in scientific journals, and a tailored development and implementation process will follow if the SNC16 is found safe and effective. TRIAL REGISTRATION NUMBER: NCT05964764.

A Predictive Noninvasive Single-Nucleotide Variation-Based Biomarker Signature for Resectable Pancreatic Cancer: Protocol for a Prospective Validation Study.

BACKGROUND: Single-nucleotide variations (SNVs; formerly SNPs) are inherited genetic variants that can be easily determined in routine clinical practice using a simple blood or saliva test. SNVs have potential to serve as noninvasive biomarkers for predicting cancer-specific patient outcomes after resection of pancreatic ductal adenocarcinoma (PDAC). Two recent analyses led to the identification and validation of three SNVs in the CD44 and CHI3L2 genes (rs187115, rs353630, and rs684559), which can be used as predictive biomarkers to help select patients most likely to benefit from pancreatic resection. These variants were associated with an over 2-fold increased risk for tumor-related death in three independent PDAC study cohorts from Europe and the United States, including The Cancer Genome Atlas cohorts (reaching a P value of 1×10-8). However, these analyses were limited by the inherent biases of a retrospective study design, such as selection and publication biases, thereby limiting the clinical use of these promising biomarkers in guiding PDAC therapy. OBJECTIVE: To overcome the limitations of previous retrospectively designed studies and translate the findings into clinical practice, we aim to validate the association of the identified SNVs with survival in a controlled setting using a prospective cohort of patients with PDAC following pancreatic resection. METHODS: All patients with PDAC who will undergo pancreatic resection at three participating hospitals in Switzerland and fulfill the inclusion criteria will be included in the study consecutively. The SNV genotypes will be determined using standard genotyping techniques from patient blood samples. For each genotyped locus, log-rank and Cox multivariate regression tests will be performed, accounting for the relevant covariates American Joint Committee on Cancer stage and resection status. Clinical follow-up data will be collected for at least 3 years. Sample size calculation resulted in a required sample of 150 patients to sufficiently power the analysis. RESULTS: The follow-up data collection started in August 2019 and the estimated end of data collection will be in May 2027. The study is still recruiting participants and 142 patients have been recruited as of November 2023. The DNA extraction and genotyping of the SNVs will be performed after inclusion of the last patient. Since no SNV genotypes have been determined, no data analysis has been performed to date. The results are expected to be published in 2027. CONCLUSIONS: This is the first prospective study of the CD44 and CHI3L2 SNV-based biomarker signature in PDAC. A prospective validation of this signature would enable its clinical use as a noninvasive predictive biomarker of survival after pancreatic resection that is readily available at the time of diagnosis and can assist in guiding PDAC therapy. The results of this study may help to individualize treatment decisions and potentially improve patient outcomes. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/54042.

Validez y fiabilidad del cuestionario ARMS-e en pacientes con Diabetes mellitus tipo 2 / Validity and reliability of the ARMS-e questionnaire in patients with type 2 Diabetes mellitus

Introducción: El cuestionario “Adherence to Refills and Medications Scale” (ARMS) se diseñó para medir adherencia al tratamiento. Fue traducido y adaptado al español, pero no se han evaluado sus propiedades psicométricas. El objetivo fue evaluar dichas propiedades en una población con diabetes mellitus tipo 2. Método: El estudio se llevó a cabo en farmacias comunitarias de Granada (España) mediante entrevista. Se realizó un análisis factorial de componentes principales (AFCP) con rotación Varimax (validez de constructo), un análisis de concordancia (validez de criterio concurrente y fiabilidad por estabilidad temporal) y alfa de Cronbach y correlación ítem-total (fiabilidad por homogeneidad). Resultados: 107 pacientes entraron en el estudio. El 54,2 % (58) fueron hombres y la edad media fue 70,5 años (D.E.: 9,7). El AFCP extrajo 4 factores que explicaron el 57,49 % de la varianza total. El alfa de Cronbach= 0,428 y el test-retest κ= 0,627 (p > 0,001). Conclusiones: El ARMS-e no puede ser considerado una herramienta útil para medir la adherencia al tratamiento antidiabético oral en esta muestra. (AU)

Introduction: The Adherence to Refills and Medications Scale questionnaire (ARMS) was designed to measure ad-herence to treatment. It was translated and adapted into Spanish, but its psychometric properties have not been evaluated. The aim was to evaluate these properties in a population with type 2 diabetes mellitus. Method: The study was carried out in community pharmacies in Granada (Spain) by interview. A principal compo-nent factor analysis (PCA) with Varimax rotation (construct validity), a concordance analysis (concurrent criterion validity and reliability by temporal stability) and Cronbach’s alpha and item-total correlation (reliability by homo-geneity) were performed. Results: 107 patients entered the study. 54.2 % (58) were male and the mean age was 70.5 (SD: 9.7). The PCA extract-ed 4 factors that explained 57.49 % of the total variance. Cronbach’s alpha= 0.428, and in the test-retest κ= 0.627 (p > 0.001). Conclusions: The ARMS-e cannot be considered a useful tool to measure adherence to oral antidiabetic treatment in this sample. (AU)

The benefits of validation of methods for toxicity testing outweigh its costs

The 4th Annual Forum on Endocrine Disrupters organized by the European Commission brought together the authors of this article around the topic: "From bench to validated test guidelines: (pre)val­idation of test methods". Validation activities are meant to demonstrate the relevance and reliability of methods and approaches used in regulatory safety testing. These activities are essential to facil­itate regulatory use, still they are largely underfunded and unattractive to the scientific community. In the last decade, large amounts of funding have been invested in European research towards the development of approaches that can be used in regulatory decision-making, including for the identification of endocrine disrupters. There is a vast pool of candidate test methods for potential reg­ulatory applications, but most of them will not be used due to the absence of consideration of their relevance and reliability outside the method developer's laboratory. This article explains the reasons why such a gap exists between the outputs of research projects and the uptake in a regulatory context. In parallel, there are also increasing expectations from the regulatory science community that validation becomes more efficient with respect to time and resources. This article shares some of the lessons learned and proposes paths forward for validation of new methods that are not intended as one-to-one replacements of animal studies. This includes submitting only mature methods for validation that were developed following good practices and good documentation, proposing a greater emphasis on well-documented transferability studies, and adopting a cost-sharing model among those who benefit from validated methods.

Validation activities for methods intended to be used to assess chemical safety have a cost but also bring substantial benefits when the validated methods are established as OECD Test Guidelines, which results in mutual acceptance of data generated by the methods across OECD member and adhering countries. The article discusses some of the challenges faced when method validation is underfunded and unattractive for researchers. Proposals are made to improve the current situation, gain efficiency, and make validation a shared responsibility.

Validación de la escala Short FES-I en población española mayor de 70 años / Validation of the short FES-I scale in Spanish population over 70 years

Introducción Las caídas deterioran la calidad de vida de los ancianos y el miedo a estas ha demostrado ser un factor de riesgo independiente para fragilidad, por lo que es prioritario disponer de herramientas para su evaluación. La escala ShortFalls Efficacy Scale-International (FES)-I, versión corta (siete ítems) de la escala FES-I (16 ítems), evalúa el miedo a caer (MC). El objetivo de este estudio es validar la escala Short FES-I en población española mayor de 70 años y analizar la relación entre el miedo a las caídas, el riesgo de las mismas y la fragilidad. Material y métodos Se trata de un estudio observacional transversal. La muestra consistió en 227 sujetos (50,7% varones; edad media 75,8 años). La ubicación fue en el norte de España. Las variables empleadas fueron sociodemográficas, clínicas, pruebas de ejecución Short Physical Performance Battery (SPPB) y Timed Up and Go Test (TUG), FES-I y Short FES-I. Se analizaron las propiedades psicométricas: validez y fiabilidad. Resultados La escala Short FES-I muestra excelentes consistencia interna (alfa de Cronbach = 0,90, coeficiente correlación intraclase = 0,89) y reproducibilidad test-retest (Rho Spearman = 0,76). Tiene una elevada validez de criterio concomitante analizada por su correlación con FES-I (Rho Spearman = 0,90). La validez de constructo discriminante ha sido confirmada tanto para SPPB como TUG. Short FES-I presenta buena capacidad de clasificación de fragilidad (definida por SPPB) con área bajo la curva [AUC] = 0,715; como punto de corte se propone un valor Short FES-I>8 para miedo moderado/alto de caídas. Conclusiones La escala Short FES-I es un buen instrumento para estudiar el miedo a las caídas en población española mayor de 70 años y es válida para su uso clínico y en investigación. (AU)

Introduction Falls deteriorate the quality of life of the elderly and the fear of falling has been shown to be an independent risk factor for frailty, so having tools for its evaluation is a priority. The short FES-I scale, short version (7 items) of the FES-I scale (16 items), assesses fear of falling. The objective of this study is to validate the short FES-I scale in the Spanish population over 70 years and to analyze the relationship between fear of falling, risk of falls and frailty. Material and methods Cross-sectional observational study. Sample: 227 subjects (50.7% male; mean age 75.8 years). Setting: northern Spain. Variables: sociodemographic, clinical, short physical performance battery (SPPB) and timed up and go test (TUG) execution tests, FES-I and short FES-I. Analysis of psychometric properties: validity and reliability. Results The short FES-I scale shows excellent internal consistency (Cronbach's alpha = 0.90, intraclass correlation coefficient = 0.89) and test–retest reliability (rho Spearman = 0.76). It has a high concomitant criterion validity analyzed by its correlation with FES-I (rho Spearman = 0.90). The discriminant construct validity has been confirmed for both SPPB and TUG. Short FES-I presents good capacity for frailty classification (defined by SPPB) with AUC = 0.715. As a cut-off point, a short FES-I value > 8 is proposed for moderate/high fear of falling. Conclusions The short FES-I scale is a good instrument to study fear of falling in the Spanish population over 70 years and is valid for clinical and research use. (AU)

Validación de la escala Short FES-I en población española mayor de 70 años / Validation of the short FES-I scale in Spanish population over 70 years

Introducción Las caídas deterioran la calidad de vida de los ancianos y el miedo a estas ha demostrado ser un factor de riesgo independiente para fragilidad, por lo que es prioritario disponer de herramientas para su evaluación. La escala ShortFalls Efficacy Scale-International (FES)-I, versión corta (siete ítems) de la escala FES-I (16 ítems), evalúa el miedo a caer (MC). El objetivo de este estudio es validar la escala Short FES-I en población española mayor de 70 años y analizar la relación entre el miedo a las caídas, el riesgo de las mismas y la fragilidad. Material y métodos Se trata de un estudio observacional transversal. La muestra consistió en 227 sujetos (50,7% varones; edad media 75,8 años). La ubicación fue en el norte de España. Las variables empleadas fueron sociodemográficas, clínicas, pruebas de ejecución Short Physical Performance Battery (SPPB) y Timed Up and Go Test (TUG), FES-I y Short FES-I. Se analizaron las propiedades psicométricas: validez y fiabilidad. Resultados La escala Short FES-I muestra excelentes consistencia interna (alfa de Cronbach = 0,90, coeficiente correlación intraclase = 0,89) y reproducibilidad test-retest (Rho Spearman = 0,76). Tiene una elevada validez de criterio concomitante analizada por su correlación con FES-I (Rho Spearman = 0,90). La validez de constructo discriminante ha sido confirmada tanto para SPPB como TUG. Short FES-I presenta buena capacidad de clasificación de fragilidad (definida por SPPB) con área bajo la curva [AUC] = 0,715; como punto de corte se propone un valor Short FES-I>8 para miedo moderado/alto de caídas. Conclusiones La escala Short FES-I es un buen instrumento para estudiar el miedo a las caídas en población española mayor de 70 años y es válida para su uso clínico y en investigación. (AU)

Introduction Falls deteriorate the quality of life of the elderly and the fear of falling has been shown to be an independent risk factor for frailty, so having tools for its evaluation is a priority. The short FES-I scale, short version (7 items) of the FES-I scale (16 items), assesses fear of falling. The objective of this study is to validate the short FES-I scale in the Spanish population over 70 years and to analyze the relationship between fear of falling, risk of falls and frailty. Material and methods Cross-sectional observational study. Sample: 227 subjects (50.7% male; mean age 75.8 years). Setting: northern Spain. Variables: sociodemographic, clinical, short physical performance battery (SPPB) and timed up and go test (TUG) execution tests, FES-I and short FES-I. Analysis of psychometric properties: validity and reliability. Results The short FES-I scale shows excellent internal consistency (Cronbach's alpha = 0.90, intraclass correlation coefficient = 0.89) and test–retest reliability (rho Spearman = 0.76). It has a high concomitant criterion validity analyzed by its correlation with FES-I (rho Spearman = 0.90). The discriminant construct validity has been confirmed for both SPPB and TUG. Short FES-I presents good capacity for frailty classification (defined by SPPB) with AUC = 0.715. As a cut-off point, a short FES-I value > 8 is proposed for moderate/high fear of falling. Conclusions The short FES-I scale is a good instrument to study fear of falling in the Spanish population over 70 years and is valid for clinical and research use. (AU)

Current Knowledge about ActiGraph GT9X Link Activity Monitor Accuracy and Validity in Measuring Steps and Energy Expenditure: A Systematic Review.

Over recent decades, wearable inertial sensors have become popular means to quantify physical activity and mobility. However, research assessing measurement accuracy and precision is required, especially before using device-based measures as outcomes in trials. The GT9X Link is a recent activity monitor available from ActiGraph, recognized as a "gold standard" and previously used as a criterion measure to assess the validity of various consumer-based activity monitors. However, the validity of the ActiGraph GT9X Link is not fully elucidated. A systematic review was undertaken to synthesize the current evidence for the criterion validity of the ActiGraph GT9X Link in measuring steps and energy expenditure. This review followed the PRISMA guidelines and eight studies were included with a combined sample size of 558 participants. We found that (1) the ActiGraph GT9X Link generally underestimates steps; (2) the validity and accuracy of the device in measuring steps seem to be influenced by gait speed, device placement, filtering process, and monitoring conditions; and (3) there is a lack of evidence regarding the accuracy of step counting in free-living conditions and regarding energy expenditure estimation. Given the limited number of included studies and their heterogeneity, the present review emphasizes the need for further validation studies of the ActiGraph GT9X Link in various populations and in both controlled and free-living settings.