P169 Usability of a home-based test for the measurement of fecal calprotectin in IBD patients

Abstract

Background: Fecal calprotectin (FC) correlates well with mucosal healing and risk of relapse in inflammatory Bowel Disease (IBD). An obstacle for a broader use of FC measurement in routine practice is the need to bring stool samples at the hospital or the send them by mail. The aim of our work was to test the usability of a home-based test for the measurement of FC in IBD patients. Methods: IBD patients in clinical remission or mild disease activity and declaring motivation to perform home-based FC measurements were prospectively recruited in three IBD centres in Oslo, Barcelona and Liège. They received a standardized training. They were instructed to collect and extract stools and to measure FC with a dedicated tool and smartphone application, 5 times at two weeks intervals over a 8 weeks period. The included patients had to fill in a usability questionnaire made of simple questions and Linkert scales at the first and the last FC measurement. Two global scores were calculated integrating the different aspects of usability: the System Usability Scale (SUS: 0–100) and the Global Usability Score (GUS: 0–85). FC was also centrally measured by ELISA. Results: 58 patients were recruited, including 18 ulcerative colitis (UC) and 40 Crohn's disease (CD), 30 females. Median (IQR) age was 35 yrs (27–40), median (IQR) HBI in CD was 0 (0–4), median (IQR) Clinical Mayo in UC was 0 (0–1). Over the 58 included patients, 42 performed at least one FC measurement and 27 performed all the FC requested measurements. The median (IQR) GUS (0–85) at the first and last use were 74 (69–80) and 77 (68–83), respectively; the median (IQR) SUS (0–100) at the first and last use were 85 (78–90) and 81 (70–88), respectively. Adherence to the planned measurements and usability of the tool were higher in females and in less severe disease. The inter-class correlation coefficient between home-based and centrally measured FC was 0.85. Conclusions: Around three quarters of the patients who declared themselves motivated to use home-based test of FC measurement actually did it, but only half of them fully adhered to the planned measurements. Usability scores for the home-based test were high. There was a very good correlation with the centrally measured FC by ELISA.