Pressure injury incidence measurement as a quality improvement strategy: national trends in Switzerland.

Objective: This study sought to determine the risk-adjusted (controlled for patient characteristics) trend in pressure injury (PI) incidence in Switzerland.

Method: A secondary data analysis was conducted. The data originated from the national PI quality measurement based on a multicentre cross-sectional design with repeated annual measurements. Descriptive statistics, a Cochran-Armitage trend test and logistic (multilevel) regression modelling were applied.

Results: The analysis sample comprised 123,715 patients from 230 hospitals over 10 survey years (2011-2019 and 2022). The incidence of descriptive PI varied in Switzerland between 3.7% and 5.6% over the survey years. No linear trend could be found when patient characteristics were not considered. A non-linear trend was detected when controlling for patient characteristics and the time effect (repeated measurement). This was also reflected in the plotted risk-adjusted incidence, which revealed a decrease followed by a levelling off. When only considering the incidence of PIs rated category 2 and higher, there was also a non-linear decreasing trend when controlling for patient characteristics and time effects. If the incidence per survey year were estimated on the basis of patient characteristics, an increase in the incidence would have been expected.

Conclusion: Although patients' risk of developing a PI increased between 2011-2022, the incidence of PIs in Switzerland first decreased and then levelled off. The results indicated that care quality in Swiss hospitals has improved regarding PIs. Nevertheless, in view of demographic trends and increasing staff shortages, it is important to continue to monitor PI incidence and to invest in PI prevention.