Simple, sensitive, specific self-sampling assay secures SARS-CoV-2 antibody signals in sero-prevalence and post-vaccine studies.

At-home sampling is key to large scale seroprevalence studies. Dried blood spot (DBS) self-sampling removes the need for medical personnel for specimen collection but facilitates specimen referral to an appropriately accredited laboratory for accurate sample analysis. To establish a highly sensitive and specific antibody assay that would facilitate self-sampling for prevalence and vaccine-response studies. Paired sera and DBS eluates collected from 439 sero-positive, 382 sero-negative individuals and DBS from 34 vaccine recipients were assayed by capture ELISAs for IgG and IgM antibody to SARS-CoV-2. IgG and IgM combined on DBS eluates achieved a diagnostic sensitivity of 97.9% (95%CI 96.6 to 99.3) and a specificity of 99.2% (95% CI 98.4 to 100) compared to serum, displaying limits of detection equivalent to 23 and 10 WHO IU/ml, respectively. A strong correlation (r = 0.81) was observed between serum and DBS reactivities. Reactivity remained stable with samples deliberately rendered inadequate, (p = 0.234) and when samples were accidentally damaged or 'invalid'. All vaccine recipients were sero-positive. This assay provides a secure method for self-sampling by DBS with a sensitivity comparable to serum. The feasibility of DBS testing in sero-prevalence studies and in monitoring post-vaccine responses was confirmed, offering a robust and reliable tool for serological monitoring at a population level.

Video-assisted reflection: improving OSCE feedback.

BACKGROUND: Objective Structured Clinical Examinations (OSCEs) are commonly used to provide feedback to students on their performance in formative examinations. However, students are often unable to act independently on the feedback they receive. This study explored how the use of video-assisted reflection in OSCEs can enhance students' ability to reflect and engage in sustainable feedback. METHODS: Twenty-one students undertaking a mock-final OSCE consented to have one of their examination stations filmed. Participants completed a series of reflective forms immediately after the OSCE, after verbal feedback from an examiner and finally, after watching the video of their own performance. Students were asked to predict their overall grade as well as list areas for improvement. Pearson r correlations examined the relationship between the examiners' grades and the candidates' self-predicted grades. Wilcoxon signed-rank tests were used to compare the length of reflections at each stage. Semi-structured interviews were conducted to explore students' beliefs on self-efficacy and how the video-assisted reflection altered their ability to act on feedback. RESULTS: The students' ability to self-assess and gauge their own performance improved significantly after undertaking the video-assisted reflection (p < 0.01). Furthermore, video-assisted reflection significantly increased the length of the student's reflections. In interviews, participants described multiple ways in which the video-assisted reflection improved their confidence and ability to act on feedback, highlighting a clear enhancement in self-efficacy. DISCUSSION: Video-assisted reflection of recorded OSCE stations represents an effective approach to increase student self-efficacy and subsequently improve engagement in sustainable feedback practice.