4.4 Clinical relevance and outlook
Although there is a significant change with the corrected algorithm, we show that the clinimetric properties of LCI still hold. This means that clinical utility and our understanding of LCI and its changes remain valid. This also suggests that previously published papers do not need to be withdrawn. However, this implies also that for absolute correct estimation of effect sizes, previously published datasets need to be reanalyzed to enable comparison with results from Spiroware 3.3.1. Besides, we will need to closely evaluate changes within individuals applying the new software, to adjust individual therapeutic goals but also to capture individual disease progression at this new level. The option of retrospective correction has the great advantage that all previously collected data in Spiroware can be reanalyzed and corrected.
Conclusion
Our study confirms that clinimetric properties of LCI remain unaffected after correction for the recently detected measurement error in the widely used Spiroware software. However, the correction results in lower LCI values, with the concurrent need to redefine existing thresholds and adjust clinical understanding of LCI and its changes on this new level.
Acknowledgements
We thank all our patients and study participants as well as their families for allowing their MBW data to be used for research. In addition, we thank the lab technicians and study nurses for their contribution by performing MBW measurements. Furthermore, we thank the physicians from our department, especially Insa Korten and Elisabeth Kieninger.
Funding
This project was funded by the Swiss National Science Foundation, Grant Nos. 182719 (to P. Latzin) and 179905 (to S. Yammine).
Author contributions
Bettina Sarah Frauchiger: Conceptualization, Methodology, Formal analysis, Investigation, Resources, Writing - Original Draft, Review & Editing, Visualization.
Marc-Alexander Oestreich: Conceptualization, Data Curation, Methodology, Formal analysis, Investigation, Resources, Writing - Original Draft, Review & Editing, Visualization.
Florian Wyler: Software.
Nathalie Monney: Resources.
Corin Willers: Resources.
Sophie Yammine: Writing - Original Draft, Review & Editing.
Philipp Latzin: Conceptualization, Supervision, Project administration, Funding acquisition.
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