Prediction models aim to use available data to predict a health state or outcome that has not yet been observed. Prediction is primarily relevant to clinical practice, but is also used in research, and administration. While prediction modeling involves estimating the relationship between patient factors and outcomes, it is distinct from casual inference. Prediction modeling thus requires unique considerations for development, validation, and updating. This document represents an effort from editors at 31 respiratory, sleep, and critical care medicine journals to consolidate contemporary best practices and recommendations related to prediction study design, conduct, and reporting. Herein, we address issues commonly encountered in submissions to our various journals. Key topics include considerations for selecting predictor variables, operationalizing variables, dealing with missing data, the importance of appropriate validation, model performance measures and their interpretation, and good reporting practices. Supplemental discussion covers emerging topics such as model fairness, competing risks, pitfalls of “modifiable risk factors”, measurement error, and risk for bias. This guidance is not meant to be overly prescriptive; we acknowledge that every study is different, and no set of rules will fit all cases. Additional best practices can be found in the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines, to which we refer readers for further details.
Control of Confounding and Reporting of Results in Causal Inference Studies. Guidance for Authors from Editors of Respiratory, Sleep, and Critical Care Journals
Abstract Objective: Sleep disturbance and sexual dysfunction are common in menopause; however, the nature of their association is unclear. The present study aimed to determine whether sleep characteristics were associated with sexual activity and sexual satisfaction. Methods: Sexual function in the last year and sleep characteristics (past 4 wk) were assessed by self-report at baseline for 93,668 women age 50 to 79 years enrolled in the Women's Health Initiative (WHI) Observational Study (OS). Insomnia was measured using the validated WHI Insomnia Rating Scale. Sleep-disordered breathing (SDB) risk was assessed using questions adapted from the Berlin Questionnaire. Using multivariate logistic regression, we examined cross-sectional associations between sleep measures and two indicators of sexual function: partnered sexual activity and sexual satisfaction within the last year. Results: Fifty-six percent overall reported being somewhat or very satisfied with their current sexual activity, and 52% reported partnered sexual activity within the last year. Insomnia prevalence was 31%. After multivariable adjustment, higher insomnia scores were associated with lower odds of sexual satisfaction (yes/no) (odds ratio [OR] 0.92, 95% CI, 0.87-0.96). Short sleep duration (<7-8 h) was associated with lower odds of partnered sexual activity (yes/no) (≤5 h, OR 0.88, 95% CI, 0.80-0.96) and less sexual satisfaction (≤5 h, OR 0.88, 95% CI, 0.81-0.95). Conclusions: Shorter sleep durations and higher insomnia scores were associated with decreased sexual function, even after adjustment for potential confounders, suggesting the importance of sufficient, high-quality sleep for sexual function. Longitudinal investigation of sleep and its impact on sexual function postmenopause will clarify this relationship.