PURPOSE T in Swedish hospital wards and nursing homes A psychometric evaluation of a new pressure ulcer risk assessment instrument.

Aim To evaluate the psychometric characteristics of the Pressure Ulcer Risk Primary or Secondary Evaluation Tool (PURPOSE T); reliability (inter-rater and test-retest) and validity (convergent validity) in a Swedish context. Background Pressure ulcers are considered as an adverse event and is a problem in healthcare worldwide. The first step in pressure ulcer prevention is to identify patients that are at risk. PURPOSE T is a new pressure ulcer risk assessment instrument that was developed in the UK using "golden standard" instrument method. Design Observational, descriptive and comparative. Methods A total of 235 patients and 28 registered nurses were recruited (May 2018 - November 2018) from six hospital wards at a university hospital and two community nursing homes in Sweden. Blinded (ward/nursing home nurses and expert nurses) PURPOSE T assessments and follow-up retests were undertaken. Cross-tabulation and kappa statistics were used to examine the reliability, and phi correlation was used to test the convergent validity. The study followed the STROBE guideline. Results The clinical evaluation showed "very good" (kappa) inter-rater and test-retest reliability for PURPOSE T assessment decision overall. The agreement of "at risk"/"not at risk" for both inter-rater and test-retest was also high, at least 95.5%. The convergent validity between PURPOSE T and other traditional assessment instruments was moderate. Conclusion The evaluation of PURPOSE T demonstrated good psychometric characteristics. Further research is needed to evaluate PURPOSE T´s usability among registered nurses. Relevance to clinical practice There is a lack of evidence based validated pressure ulcer risk assessment instruments for use in health care. According to our findings, the Swedish version of PURPOSE T could be used in hospitals and nursing homes to identify patients in risk or with pressure ulcers.