Semi-virtual patch testing: a review of the clinical impact, practicalities, patient experience and environmental impact in a tertiary dermatology centre

ABSTRACT

The COVID-19 pandemic has influenced the way patch testing is carried out at our tertiary centre. From July 2020 we introduced 'semi-virtual patch testing', where suitable patients remove patches at home on day 2 (D2) and take photos, which were reviewed during the D4 face-to-face appointment. Our aim was to assess the continued efficacy and practicality of this service, as well as the photo quality, patient satisfaction and environmental impact of the changes. Data were collected from patients attending patch testing at the Bristol Royal Infirmary from August to December 2021. Patients/carers were asked at their D4 clinic appointment to complete a pre-prepared questionnaire, with their consent, regarding their patch test experience. A clinician (consultant or clinical fellow) concurrently filled out a questionnaire on image quality. These data were collated with data obtained via telephone questionnaires (July-November 2020). Data were available for 181 patients (age range 0-89 years, 74.8% female and 25.2% male). Ninety-seven per cent (n = 135/139) were happy to have patch testing during the pandemic. Ninety-three per cent (n = 130/140) removed their patches at home on D2. Only 3.9% (n = 5/129) would have preferred to attend hospital. Information was provided by multiple sources verbally by a nurse (95.2%), a doctor (60.7%), a written information sheet (88.1%) and a video (29.8%). Almost all patients (n = 127/ 136) felt confident/fairly confident removing the patches at home, and 85.0% (n = 108/127) reported it saved > 1 h. Seventy-four per cent (n = 95/129) would have had to take time off work/caring commitments to attend. Almost all patients (n = 131/135) reported that their overall experience was good or very good. Seventy per cent (n = 59/84) of patients travelled independently to their appointment, and 79.8% (n = 67/84) came by car/taxi. The mean mileage (one way) to attend the appointment was 13.3 (range 0.2-46.5;n = 98). Ninety-seven percent (n = 89/92) used a smartphone device for D2 photos. The overall presentation of the D2 reading was clear in 91.2% (n = 83/91), adequate in 6.6% (n = 6/91) and inadequate in 2.2% (n = 2/91). Image focus and colour exposure was good/adequate in 97.8% (n = 90/92) and 97.2% (n = 70/72), respectively. Virtual reading negatively affected the final interpretation of the patch test in 2.2% (n = 2/89) of patients and 9.4% (n = 16/170) would have had additional tests added on D2 if they had attended, the results of which were followed-up virtually. Our review of semi-virtual patch testing in our centre demonstrates this method as being an excellent option for most patients, with very limited adverse clinical impact. There were high levels of patient satisfaction, a reduced need for time away from work/home and a reduction in travel required. The vast majority of patients can competently remove their patch tests and produce high-quality images with good focus and colour exposure, mostly using smartphone technology.