Septoplasty: defining a desirable clinical outcome according to baseline symptom scores

In biomedical research and practice, quantitative tests or biomarkers are often used for diagnostic or screening purposes, with a cut point established on the quantitative measurement to aid binary classification. This paper introduces an alternative to the traditional methods based on the Youden index and the closest-to-(0, 1) criterion for threshold selection. A concordance probability evaluating the classification accuracy of a dichotomized measure is defined as an objective function of the possible cut point. A nonparametric approach is used to search for the optimal cut point maximizing the objective function. The procedure is shown to perform well in a simulation study. Using data from a real-world study of arsenic-induced skin lesions, we apply the method to a measure of blood arsenic levels, selecting a cut point to be used as a warning threshold. Copyright © 2012 John Wiley & Sons, Ltd. Show more

Background The aim of this systematic review is to describe the different types of anchors and statistical methods used in estimating the Minimal Clinically Important Difference (MCID) for Health-Related Quality of Life (HRQoL) instruments. Methods PubMed and Google scholar were searched for English and French language studies published from 2010 to 2018 using selected keywords. We included original articles (reviews, meta-analysis, commentaries and research letters were not considered) that described anchors and statistical methods used to estimate the MCID in HRQoL instruments. Results Forty-seven papers satisfied the inclusion criteria. The MCID was estimated for 6 generic and 18 disease-specific instruments. Most studies in our review used anchor-based methods (n = 41), either alone or in combination with distribution-based methods. The most common applied anchors were non-clinical, from the viewpoint of patients. Different statistical methods for anchor-based methods were applied and the Change Difference (CD) was the most used one. Most distributional methods included 0.2 standard deviations (SD), 0.3 SD, 0.5 SD and 1 standard error of measurement (SEM). MCID values were very variable depending on methods applied, and also on clinical context of the study. Conclusion Multiple anchors and methods were applied in the included studies, which lead to different estimations of MCID. Using several methods enables to assess the robustness of the results. This corresponds to a sensitivity analysis of the methods. Close collaboration between statisticians and clinicians is recommended to integrate an agreement regarding the appropriate method to determine MCID for a specific context. Show more

Our goal was to assess disease-specific quality of life outcomes after nasal septoplasty in adults with nasal obstruction. We conducted a prospective observational outcomes multicenter study with 14 sites and 16 investigators, including private practice and academic settings. Patients had had septal deviation and symptomatic nasal obstruction for at least 3 months, and medical management had failed. Patients with septal deviation completed a validated outcomes instrument (the Nasal Obstruction Septoplasty Effectiveness [NOSE] scale) before and 3 and 6 months after septoplasty, with or without partial turbinectomy. Fifty-nine patients underwent surgery; there was a significant improvement in mean NOSE score at 3 months after septoplasty (67.5 versus 23.1, P < 0.0001), and this improvement was unchanged at 6 months. Patient satisfaction was very high, and patients used significantly fewer nasal medications. In patients with septal deformity, nasal septoplasty results in significant improvement in disease-specific quality of life, high patient satisfaction, and decreased medication use. Show more