Page 27 - Exploring the Potential of Self-Monitoring Kidney Function After Transplantation - Céline van Lint

Patient experiences with self-monitoring after transplantation 25
interview data were only used to facilitate interpretation of quantitative results, no further formal coding and analysis was conducted.
Self-monitoring procedure
Prior or immediately following transplantation, patients received instructions about how to perform, interpret and record the creatinine and blood pressure measures.
For self-monitoring creatinine, each participant received a StatSensor® Xpress-iTM Creatinine Hospital Meter (Nova Biomedical, Waltham, USA; certified according to ISO 13485:2003, IVDD, meets IEC 61010, UL and FDA labelled for in-vitro diagnostic use), and measurement accessories (i.e. test strips, control solution to test the quality of the strips, and safety lancets for capillary blood sampling). Although the devices’ accuracy for detecting current kidney function with a single creatinine measurement is debated 28-31, it seems suitable for monitoring creatinine trends with serial creatinine measurements in kidney transplant patients.31 It is important to distinguish between these applications, as this determines the analytical performance requirements of the device.32 In case of trend monitoring, the accuracy of a single creatinine test result is less critical as test results are used to detect changes between sequential measurements. Patients received specific instructions about how to interpret sequential results, rather than single measurements. Further, values registered in the online DMS were depicted in a graph to support trend-wise interpretation of test results.
For self-monitoring blood pressure, each participant received a Microlife WatchBP® Home (Microlife, Heerbrugg, Switzerland), an oscillometric device for blood pressure self-measurement on the upper arm. The Microlife WatchBP® Home fulfils the validation requirements of the ESH International Protocol for self-monitoring blood pressure at home.33
Questionnaires
Both validated and questionnaires that were specifically developed for the study were used. We measured level of general and more specific satisfaction, experience with self-monitoring, amount of transplant related worries (Worry scale, Transplant Effects Questionnaire34, trust in own monitoring skills (self-efficacy) and patients’ perception of the level of autonomy support from their physician (Health Care Climate Questionnaire35). Item examples, answering scales and time of application are listed in table 1.
Demographics that could not easily be extracted from the hospital system (marital status, nationality, educational level and Internet use) were self-reported at baseline. Education level was based on the highest level of education accomplished, and categorized in three categories according to the International Standard Classification of Education (ISCED) (i.e. low, middle and high level).36
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