The development, validation and application of remote blood sample collection in telehealth programmes

Abstract

Introduction: The ability to collect blood samples remotely without the involvement of healthcare professionals is a key element of future telehealth applications. We developed and validated the application of the Drawbridge OneDraw device for use at home for blood sample collection. The device was then applied in a large population-based remote monitoring study to assess changes in SARS-CoV-2 IgG antibody levels.

Methods: We tested: (1) feasibility of participants using the device at home without a healthcare professional on the upper arm and thigh sites (2) stability of the dried blood sample collected remotely (3) participant acceptability of the device compared with finger-prick and venous blood samples and the validity of SARS-CoV-2 virus antibody measurement versus venous blood sample (4) application to the Fenland COVID-19 study in which 4023 participants at 3 timepoints across 6 months.

Results: Participant acceptability was high, with a significantly lower median perceived pain score and 76% of participants preferring the OneDraw device over the other blood collection methods. There was high level of agreement in SARS-CoV-2 virus antibody results with venous blood samples in 120 participants (Cohen's kappa 0.68 (95% CI 0.56, 0.83). In the Fenland COVID-19 study, 92% of participants returned a sample at baseline (3702/4023), 89% at 3 months (3492/3918) and 93% at 6 months (3453/3731), with almost all samples received successfully processed (99.9%).

Discussion: The OneDraw device enables a standardised blood sample collection at home by participants themselves. Due to its ease-of-use and acceptability the OneDraw device is particularly useful in telehealth approaches where multiple samples need to be collected.

Keywords: Home telecare; blood sampling; pathology; self-care; telehealth.

Figure 1.

Validation study of blood sample collected by OneDraw device versus venous serum sample. a) Venous blood collection by trained phlebotomist in appropriate personal protection; b) OneDraw device that allows blood collection at home; c) Pearson correlation between SARS-CoV-2 IgG antibody ELISA cut-off ratios from venous serum samples versus dried blood sample from OneDraw device (R² = 0.94; n = 120); d) confusion matrix of the classification of the results (n = 120, pos = positive (cut-off ratio > 1.1), neg = negative (cut-off ratio <0.8), BL = borderline (cut-off ratio <1.1 & >0.8); e) Constant Bland-Altman plot and f) proportional Bland-Altman plot showing the deviation of the SARS-CoV-2 IgG antibody ELISA results for from dried blood samples collected with the OneDraw device (n = 120).

Figure 2.

The number of positive cases and percentage of non-positive cases in the group who completed all three sample time points (n = 3208). a) Treeplot divided by pattern of positivity/negativity across the three time points (position of the three letters denote time points, P = positive, N = Negative); b) Percentage of participants who did not have a positive test; c) Stacked area plot of how participant converted from negative to positive and vice versa.