Using reference equations to standardise incremental shuttle walk test performance in children and young people with chronic conditions and facilitate the evaluation of exercise capacity and disease severity

Aims
The aim was to evaluate whether standardised exercise performance during the incremental shuttle walk test (ISWT) can be used to assess disease severity in children and young people (CYP) with chronic conditions, through (1) identifying the most appropriate paediatric normative reference equation for the ISWT, (2) assessing how well CYP with haemophilia and cystic fibrosis (CF) perform against the values predicted by the best fit reference equation and (3) evaluating the association between standardised ISWT performance and disease severity.

Methods
A cross-sectional analysis was carried out using existing data from two independent studies (2018–2019) at paediatric hospitals in London,UK. CYP with haemophilia (n=35) and CF (n=134) aged 5–18 years were included. Published reference equations for standardising ISWT were evaluated through a comparison of populations, and Bland-Altman analysis was used to assess the level of agreement between distances predicted by each equation. Associations between ISWT and disease severity were assessed with linear regression.

Results
Three relevant reference equations were identified for the ISWT that standardised performance based on age, sex and body mass index (Vardhan, Lanza, Pinho). A systematic proportional bias of standardised ISWT was observed in all equations, most pronounced with Vardhan and Lanza; the male Pinho equation was identified as most appropriate. On average, CYP with CF and haemophilia performed worse than predicted by the Pihno equation, although the range was wide. Standardised ISWT, and not ISWT distance alone, was significantly associated with forced expiratory volume in 1 s in CYP with CF. Standardised ISWT in CYP with haemophilia was slightly associated with haemophilia joint health score, but this was not significant.

Conclusions
ISWT performance may be useful in a clinic to identify those with worsening disease, but only when performance is standardised against a healthy reference population. The development of validated global reference equations is necessary for more robust assessment.

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Marzo 2024

'Family-based strategy for Helicobacter pylori infection screening: an efficient alternative to 'test and treat strategy

We read with utmost interest the study by Zhou et al,1 which was the first family-based investigation of Helicobacter pylori (Hp) infection in China. The authors provided valuable insights into the occurrence of familial cluster effect on Hp infection and the superiority of the ‘family-based strategy’. However, their work failed to compare the screening efficiency of various established Hp management methods, leaving us curious about whether the ‘family-based strategy’ could identify more Hp-infected participants with equal number of tests conducted as compared with the widely used ‘test and treat strategy’.2 Fortunately, the family-unit data in Zhou’s study offers the possibility for such exploration. To address this gap, we built a database consisting of over one million households, based on the infection status of households and individuals from 29 provinces reported by Zhou, in order to simulate real-world scenarios. The screening protocols were simulated in national…

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Marzo 2024

Celiac disease-related conditions: Who to test?

Celiac disease (CeD) is a chronic immune-mediated condition triggered by gluten consumption in genetically predisposed individuals. Approximately 1% of the general population is affected by the disorder. Disease presentation is heterogeneous, and despite growing awareness among physicians and the public, it continues to be underestimated. The most effective strategy for identifying undiagnosed CeD is proactive case-finding through serologic testing in high-risk groups. We reviewed the most recent evidence on the association between CeD and over 20 conditions.

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Marzo 2024

Diagnostic performance evaluation of urine HIV-1 antibody rapid test kits in a real-life routine care setting in China

Objectives
To evaluate the diagnostic performance of urine HIV antibody rapid test kits in screening diverse populations and to analyse subjects’ willingness regarding reagent types, purchase channels, acceptable prices, and self-testing.

Designs
Diagnostic accuracy studies

Participants
A total of 2606 valid and eligible samples were collected in the study, including 202 samples from female sex workers (FSWs), 304 persons with injection drug use (IDU), 1000 pregnant women (PW), 100 subjects undergoing voluntary HIV counselling and testing (VCT) and 1000 students in higher education schools or colleges (STUs). Subjects should simultaneously meet the following inclusion criteria: (1) being at least 18 years old and in full civil capacity, (2) signing an informed consent form and (3) providing truthful identifying information to ensure that the subjects and their samples are unique.

Results
The sensitivity, specificity and area under the curve (AUC) of the urine HIV-1 antibody rapid test kits were 92.16%, 99.92% and 0.960 (95% CI: 0.952 to 0.968, p

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Febbraio 2024

Colonoscopy vs. the Fecal Immunochemical Test: Which is Best?

While there is no debate around the effectiveness of colorectal cancer (CRC) screening in reducing disease burden, there remains a question regarding the most effective and cost-effective screening modality. Current United States guidelines present a panel of options that include the two most commonly used modalities, colonoscopy and stool testing with the fecal immunochemical test (FIT). Large-scale comparative effectiveness trials comparing colonoscopy and FIT for CRC outcomes are underway, but results not yet available.

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Febbraio 2024

Measurement properties of the incremental step test for people with chronic obstructive pulmonary disease: a cross-sectional study

Objectives
The new incremental step test (IST) is a field test that was developed for people with chronic obstructive pulmonary disease (COPD), based on the characteristics of the incremental shuttle walk test (ISWT); however, its measurement properties still need to be determined. We aimed, first, to assess the construct validity (through the comparison with the ISWT), within-day reliability and measurement error of the IST in people with COPD; and, second, to identify whether the participants have a learning effect in the IST.

Design
Cross-sectional study, conducted according to COnsensus-based Standards for the selection of health status Measurement INstruments guidelines.

Setting
A family health unit in Portugal, April 2022 to June 2023.

Participants and analysis
63 participants (67.5±10.5 years) attended two sessions to perform two IST and two ISWT, separately. Spearman’s correlations were used to compare the best performances between the IST and the ISWT. Intraclass correlation coefficient (ICC2,1) was used for reliability, and the SE of measurement (SEM), minimal detectable change at 95% CI (MDC95) and Bland and Altman 95% limits of agreement (LoA) were used for measurement error. The learning effect was explored with the Wilcoxon signed-rank test.

Results
The IST was significant and strongly correlated with the ISWT (0.72

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Febbraio 2024