Development and initial validation of the Respirator Comfort, Wearing Experience, and Function Instrument [R-COMFI]

Filtering face-piece respirators (FFRs) are worn to protect health care personnel from airborne particles; however, clinical studies have demonstrated that FFR adherence is relatively low in some settings, in part, due to discomfort and intolerance. The objective of this study was to develop and initially evaluate the psychometric properties of an instrument designed to measure the comfort and tolerability of FFRs. Instrument items were developed through literature reviews, focus groups, and several iterations of ranking and refining by experts. Psychometric evaluation of the instrument was conducted using Rasch partial credit model (PCM) analysis. Pivot anchoring was used to specify the threshold defining item difficulty; in our analyses, this was the point that participants moved from possessing none of the trait to some of the trait. The final instrument was completed by 165 health care personnel from 3 Veterans Health Administration facilities, and data were analyzed using Rasch PCM. Seven items were removed because they: (1) violated the assumption of independence; (2) were mis-fitting; and/or (3) were deemed not relevant. Category function analysis demonstrated that all categories progressed monotonically. Principal components analysis demonstrated the existence of three subscales (Discomfort, General Wearing Experience, and Function). Final reliability analyses showed that the scale had moderate to high person reliability and high item reliability. The final instrument contained 21 items. Until now, to our knowledge no instrument with evidence supporting its reliability and validity to assess discomfort and tolerance of FFRs among health care personnel has been published. A 21-item psychometrically sound measure of comfort and tolerability of FFRs, Respirator Comfort, Wearing Experience, and Function Instrument (R-COMFI), was developed. The significance of developing such an instrument is that it will help identify respirators that are likely to have better adherence in practice settings. The R-COMFI may be used within and beyond the VA healthcare system as a psychometrically sound instrument to evaluate the comfort and tolerability of respirators, including developmental prototypes.