Can we trust published evidence on point-of-care tests for cholesterol? A rapid review

Objectives
There is a need to better inform clinicians and decision-makers in primary or community care settings on selecting the appropriate point-of-care tests (POCTs) for screening purposes (as a part of the NHS Health Check Programme). Here we provide an overview of the published analytic validity and diagnostic accuracy studies on POCTs for measuring blood lipids that are available on the UK market to determine whether they meet the accuracy specifications based on the 1995 US National Cholesterol Education Program (NCEP) recommendations.

Design
Rapid review of analytical validity and diagnostic accuracy studies.

Data sources
On 12 May 2023, Medline and Embase were searched. Google Scholar was manually scrutinised to identify additional studies. Key article reference lists were also hand-searched.

Eligibility criteria
We included analytical validity and diagnostic accuracy studies that compared POCT to laboratory testing (or another POCT) performance for measuring at least total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C).

Data extraction and synthesis
Identified studies were independently reviewed by two researchers using standardised methods of screening. Where necessary, conflicts were resolved by a third reviewer. Title and abstract as well as full texts were screened using prespecified inclusion and exclusion criteria. The quality of identified studies was assessed using QUADAS-2 for diagnostic accuracy studies and a modified quality appraisal tool for studies of diagnostic reliability (QAREL) for analytical validity studies. We assessed the quality of analytical and diagnostic accuracy studies and compared the accuracy of the POCTs for TC, triglyceride (TG), HDL-C and low-density lipoprotein cholesterol (LDL-C) against NCEP standards for mean per cent bias, coefficient of variation or total error. We narratively synthesised analytical and clinical validity evidence from retrieved studies.

Results
This study examined analytical and diagnostic accuracy evidence for the selected POCTs. Through the review of 22 studies, 6 POCTs were identified. All retrieved studies were analytical validity assessments, while five of them also reported diagnostic accuracy information. The majority of evidence focused on Cholestech LDX, CardioChek PA and Accutrend Plus. Evidence of between and within-study heterogeneity was found. Precision measures often showed systematic differences between the POCT and reference standards. Most devices, except for Elemark, met at least one NCEP standard for either TC, TG, HDL-C, or LDL-C.

Conclusions
We found that evidence for two of the devices mostly met the requirements of the NCEP standard of evidence for bias and precision and could be recommended to general practitioners to use in the NHS Health Check programme. These were the Cholestech LDX and the Cobas b101 system.

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Development and evaluation of a national administrative code-based system for estimation of hospital-acquired venous thromboembolism in Ireland

Background
Hospital-acquired venous thromboembolism (HA-VTE) is a significant patient safety concern contributing to preventable deaths. Internationally, estimating HA-VTE relies on administrative codes, in particular the International Classification of Disease (ICD) codes, but their accuracy has been debated. The Irish Health Service Executive (HSE) launched a National Key Performance Indicator (KPI) in 2019 for monitoring HA-VTE rates using the Australian Modification of ICD-10 (ICD-10-AM) codes.

Objectives
This study aims to (1) describe the development of the national HSE KPI and determine the national HA-VTE occurrence rate per 1000 discharges in 2022; (2) assess the contribution of each VTE ICD-10-AM code to the national HA-VTE figure; (3) estimate the positive predictive value (PPV) of the HSE KPI against true HA-VTE, in a single large tertiary (Irish Model 4) hospital.

Methods
A retrospective observational study used national data from Irish publicly funded acute hospitals, focusing on discharges from 2022. The HSE KPI was based on an assessment of HA-VTE as a rate per 1000 hospital discharges (as per the national metadata). Inclusion criteria were inpatient only, length of stay ≥2 days, age ≥16 years and non-maternity admission type (elective or emergency only). Maternity and paediatric hospitals were excluded.
The PPV was determined through a detailed review of HA-VTE cases identified through the HSE KPI from April 2020 to October 2022 in a single large tertiary referral centre and determining the proportion indicating a true HA-VTE. Data analysis employed GraphPad Prism (Horsham, PA, USA).

Results
The national mean monthly HA-VTE rate was 11.38 per 1000 discharges in 2022. Pulmonary embolism (PE) without acute cor pulmonale (I26.9) was the most frequent contributor (59%). The mean PPV in the tertiary hospital was 0.37, with false positives attributed to acute illnesses, historical VTE coding errors and dual VTE diagnoses at admission.

Discussion
HA-VTE is a preventable cause of morbidity and mortality, necessitating accurate measurement. Administrative codes, while cost-effective and timely, reveal limitations in precision. This study identifies opportunities to improve code accuracy, address coding challenges and enhance the PPV.

Conclusion
This study provides valuable insights into estimated HA-VTE rates, the contribution of each individual ICD-10-AM code to the overall HA-VTE rate and the PPV of the measure. Ongoing refinement and quality enhancement are needed.

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