Reliability of Clinic-Obtained vs Self-Obtained Respiratory Samples From the Self-Sample Accuracy and Benefit Implementation Trial (S2wAB-IT).

BACKGROUND

Routine surveillance cultures are critical in the care of patients with cystic fibrosis (CF) and are used in clinical decision-making. Due to the improved health of people with CF (pwCF) and the increased use of telehealth for clinical care, there is a strong interest in providing remote care, including remote respiratory specimen collection.

RESEARCH QUESTION: Are self-obtained respiratory samples feasible and acceptable for pwCF and are the results comparable with clinic-obtained samples (COSs)?

STUDY DESIGN AND

METHODS

pwCF ≥ 1 year of age were enrolled at 6 CF centers (4 pediatric and 2 adult). Two oropharyngeal samples were obtained (order randomized): 1 COS per each CF center's practice and 1 self-obtained sample (SOS) after standardized education. The SOS was randomized to immediate vs delayed processing, for transport mimicry. Cohen kappa was used to assess agreement between sample types. Surveys were completed to determine feasibility and acceptability.

RESULTS

A total of 164 pwCF were enrolled. Self-collection was feasible (99% successful SOSs) and acceptable with 88% rating the collection as very easy or easy and 100% being willing to collect another sample if clinically recommended. The overall agreement between COSs and SOSs for any CF pathogen detection was 78.7% (kappa, 0.583; 95% CI, 0.432-0.734), suggesting moderate agreement. Agreement for methicillin-susceptible Staphylococcus aureus detection was 87.9% (kappa, 0.748; 95% CI, 0.594-0.902), suggesting substantial agreement. Statistical analyses were not completed for other bacterial organisms due to low detection. Order of sample collection, time to processing, participant age, or collection by self or parent/guardian did not impact agreement.

INTERPRETATION: Our results indicate that self-collection is feasible and acceptable for pwCF. Agreement between sample types suggest that self-collection may offer an alternate option for microbiology surveillance.