Usability and outcomes of self-monitored surgical wound healing using a smartphone-based application by patients following neurosurgery

Background: The Radboudumc developed a smartphone application ( WondGezond ) to collect surgical wound-healing information provided by the patient. Aim: To evaluate usability and outcomes to assess its potential for early surgical site infection (SSI) detection. Methods: Patients surgically treated for degenerative spinal disorders or carpal tunnel syndrome between August 2020 and February 2023 were enrolled one day post surgery and asked to download the app via a quick -response (QR) code. Participants uploaded a photo and answered four questions about their wound daily, for 14 days. Afterwards, participants indicated whether they received treatment for a suspected SSI (participantreported outcome). Two neurosurgeons independently assessed photos and questionnaire answers for suspected SSIs (physician-assessed outcome). The association between both outcomes was determined by calculating sensitivity, specificity, and positive and negative predictive value (PPV/NPV). Findings: After 2009 surgeries, 1695 QR-codes were distributed and 412 (21%) were activated. In all, 232 (56%) participants completed the 14 -day period of whom 22 (10%) reported SSI treatment. Physician assessment identified 15 (7%) SSIs. Concordance was reached in 88% of cases. Among 27 discordant cases were 17 false -positives and 10 falsenegatives, resulting in low sensitivity (33%) and PPV (23%), but high NPV (95%). Conclusion: WondGezond provides clinicians with information regarding wound healing and SSIs to follow-up on patients at risk, while possibly also reducing antibiotic (over) treatment and unnecessary visits for patients without issues in wound healing. However, the low participation and false -positive results render the app in its current form unsuitable for surveillance purposes. Further validation of WondGezond is required.