Defining and measuring bedtime routines in families with young children—A DELPHI process for reaching wider consensus

Introduction Bedtime routines are one of the most common family activities. They affect children’ wellbeing, development and health. Despite their importance, there is limited evidence and agreement on what constitutes an optimal bedtime routine. This study aims to reach expert consensus on a definition of optimal bedtime routines and to propose a measurement for bedtime routines. Method Four-step DELPHI process completed between February and March 2020 with 59 experts from different scientific, health and social care backgrounds. The DELPHI process started with an expert discussion group and then continued with 3 formal DELPHI rounds during which different elements of the definition and measurement of bedtime routines were iteratively refined. The proposed measurement of bedtime routines was then validated against existing data following the end of the DELPHI process. Results At the end of the four round DELPHI process and with a consistent 70% agreement level, a holistic definition of bedtime routines for families with young children between the ages of 2 and 8 years was achieved. Additionally, two approaches for measuring bedtime routines, one static (one-off) and one dynamic (over a 7-night period) are proposed following the end of the DELPHI process. A Bland-Altman difference plot was also calculated and visually examined showing agreement between the measurements that could allow them to be used interchangeably. Discussion Both the definition and the proposed measurements of bedtime routines are an important, initial step towards capturing a behavioural determinant of important health and developmental outcomes in children.

When results matter: reliable creatinine concentrations in hyperbilirubinemia patients

Background Failure to report a creatinine concentration, especially in icteric patients who are eligible for a liver transplant, can result in a life-threatening situation. We assessed the influence of bilirubin interference on several creatinine assays and investigated ways to circumvent icteric interference without interfering with our normal automated sample logistics. Methods Using icteric patient sera (total bilirubin >255 μmol/L) we determined creatinine concentrations using an enzymatic and Jaffé assay (Roche Diagnostics) in both normal (i.e. undiluted) and decreased mode (i.e. diluted) as well as an enzyme-coupled amperometric assay on a Radiometer ABL837 FLEX analyzer. Creatinine concentrations from the five methods were compared with an in-house developed LC-MS/MS method. Passing and Bablok (proportional and constant bias) as well as difference plot parameters (bias and 95% limits of agreement [LoA]) were calculated. Interferograph-based regression analysis of the enzymatic and Jaffé results was used to investigate if such an approach could be used to report corrected creatinine concentrations in icteric patient sera. Results In icteric patient sera the enzyme-coupled amperometric assay was hardly influenced by icteric interference as shown by a difference plot bias of −1.5% (95% LoA −11.6 to +8.5%). The undiluted Jaffé method had a bias of −1.4% with a very broad 95% LoA (−35.1 to +32.2%) emphasizing the poor specificity of this method. The undiluted enzymatic method had the largest bias (−13.4%, 95% LoA −35.8 to +9.0%). Diluting sera in the enzymatic method did not improve the bias (−10.5%, 95% LoA −25.4 to 4.4%), while diluting the Jaffé method resulted in a bias increase (+11.4%, 95% LoA −14.7 to 37.5%). Using interferograph-based regression analysis we were able to reliably correct enzymatic creatinine concentrations in 97 out of 100 icteric patient sera. Conclusions Analytically, quantifying creatinine in icteric sera using the Radiometer ABL837 FLEX analyzer is the method of choice within our laboratory. However, not all laboratories are equipped with this method and even if available, the limited number of highly icteric patient sera makes this method costly. For those laboratories using the Roche enzymatic method, mathematically correcting an icteric creatinine concentration using an interferograph based on an LC-MS/MS reference method is a suitable alternative to report reliable creatinine results in icteric patients.

Accuracy, user-friendliness and usefulness of the Cobas h232 point-of-care test for NT-proBNP in primary care

AimsN-terminal pro-B-type natriuretic peptide (NT-proBNP) has been shown to be useful for ruling out heart failure in primary care. In this study, we examined the accuracy of the Cobas h232 point-of-care (POC) instrument in primary care compared with an in-hospital measurement. Furthermore, we investigated the user-friendliness and usefulness of the POC device.MethodsFive general practitioner (GP) groups were asked to evaluate adult patients who were suspected of having heart failure and to test NT-proBNP with the Cobas h232. The samples were subsequently delivered to and analysed at a central hospital laboratory by the Cobas e602 using conventional transport and storage. Difference between the paired measurements was analysed using a percentage difference plot, and correlation was assessed using Passing-Bablok linear regression analysis. User-friendliness and usefulness were assessed using semistructured questionnaires.ResultsNineteen GPs studied 94 patients. Passing-Bablok analysis showed a slope of 1.05 (95% CI 1.00 to 1.11) (R2=0.97). The percentage difference plot showed a mean difference of 15.7% (95% CI −46.0% to –77.4%). User-friendliness and usefulness had median scores of 4 or 5 on a five-point Likert scale. Eighteen out of 19 GPs confirmed that the device influenced their clinical practice. During the study, GPs’ confidence in using NT-proBNP increased significantly from a mean score of 4.4 (95% CI 3.2 to 5.6) to 7.6 out of 10 (95% CI 7.1 to 8.2).ConclusionsThe Cobas h232 NT-proBNP POC test proved to be an accurate, user-friendly and useful test in primary care. Nearly all participating GPs were convinced that the test could benefit clinical decision making.