Subjective evaluation
Responses for subjective evaluation were collected from time point one, or if missing, from time point two. One participant failed to fill out the subjective evaluation questions; one participant had partial missing data. This resulted in 50 responses for the single choice and 49 to 50 responses for the usefulness rating. Participants’ evaluation in terms of usefulness was highest for the clara technique (mean 3.32, SD 0.98), followed by spectra B (mean 3.00, SD 1.08), and spectra A (mean 2.90, SD 1.10). The overall technique choice was also in favour of the clara technique, with 29 votes for clara, 11 votes for spectra B, and 10 votes for spectra A.