Optimising trial outcomes and patient retention for the MACRO trial for chronic rhinosinusitis.

Background: This study aimed to evaluate current subjective and objective outcome assessments for the MACRO (defining best Management for Adults with Chronic RhinOsinusitis) Trial which compares antibiotics, placebo and sinus surgery. This was to identify any redundant assessments and to include patient perspectives to determine acceptability for confirmation in the trial.

Methods: Adults CRS patients meeting the provisional eligibility criteria for the MACRO trial were recruited to this mixed-method study at 2 sites. Correlations between the objective outcome measures and SNOT-22 scores were evaluated. Selected participants took part in a semi-structured telephone interview to explore their experiences and views of undergoing outcome measures.

Results: Seventy patients (37% male) were recruited, 36 had CRS without nasal polyps, 34 had CRS with nasal polyps. There was a weak inverse correlation between the SNOT-22 â€Blockage†ratings and Peak Nasal Inspiratory Flow readings, a moderate inverse correlation between the SNOT-22 â€Smell†ratings and Sniffin’ Sticks scores, but no significant correlation between the SNOT-22 and Saccharin test results. The participants’ experience of the trial visit was positive with an acceptable duration of trial visit. Most proposed outcome measures were valued by participants with the exception of the Saccharin test.

Discussion: The Sniffin’ Sticks test and PNIF correlate with their respective component SNOT-22 scores but are considered important by patients; PNIF is simple, cheap test to perform. The Saccharin test will be removed as participants did not value it and was not highly rated in parallel work on a core outcome set for CRS.